In this project tutorial, Harley shows one simple way of making a trim plate for a door handle. Most door hardware is pretty standard, but occasionally some hardware may leave unsightly holes in the door. Today at the House of Hacks, we use some left over material to make door trim plates to cover ugly, unused mounting holes.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing"
Incidental: "Cool Rock"
by Kevin MacLeod at Incompetech
Sound effect: living-room-light-switch by alienxxx at FreeSound
Transcript
Today at the House of Hacks we’re going to go from this … to this.
[Intro]
Hi Makers, Builders and Do-it-yourselfers. Harley here.
Just a quick reminder, if you haven’t done so already, subscribe to the House of Hacks channel for more videos like this one. And click “Like" if you hoard left over material from projects with the hope of using it sometime in the future.
My friend Rich expanded and renovated his photography studio earlier this year and, in the process, door hardware was changed.
The previous hardware left behind some holes that Rich wanted an easy, cheap solution to fixing and/or hiding.
His studio has kind of a chic industrial look to it and I had some left over material in the scrap pile that gave me an idea.
I made a prototype, showed him, he installed it and loved it. Later in the week we made several more to meet his needs.
Let's look at how we did this.
For this build, I used:
some left over sheet metal,
some marking tools,
some cutting tools,
a smoothing tool,
some bending tools,
and a hole cutting tool.
I started with some left over galvanized sheet metal.
This is supposed to be used for heating ducts that I had left over from a home remodel project several years ago.
I cut off a piece an inch wider than we wanted the covers and long enough to cut out four more with room to spare.
Then I cut off individual squares from the long piece.
I filed the edges to remove any burrs.
Next I measured 1/2 inch from each side on the corners, drew a diagonal line through the intersection and cut off the corners.
With the corners cut, I used a small metal brake to fold over 1/2 inch on each edge.
Then I used a hammer to finish the fold by flattening it out.
A center finder gave me the center of each piece, giving me the position to drill a hole using the circle cutter.
This wasn’t the best tool for the job, but in the end got it done.
Not without a bit of mishap though.
And it did generate a bit of heat.
Afterwards, I realized I probably should have used a couple drops of cutting oil.
Also, I probably could have used a lathe tool blank to make a custom cutter that might have worked better.
But the holes still got cut, albeit with more force than finesse.
Once the holes were cut, Rich took them to the studio and installed them.
This was one of those small details that, if it wasn’t done would look bad, but in place, hardly is noticed.
All together, this took about 90 minutes to do 4 plates and didn’t require any new materials, just scraps left over from a previous project.
I’d love to hear in the comments how often you do projects using left overs? Are you like me and have a stack of materials for unknown future projects?
If this is your first time here at House of Hacks: Welcome, I’m glad you’re here and would love to have you subscribe.
I believe everyone has a God-given creative spark. Sometimes this manifests through making things with a mechanical and technical bent.
Through this channel I hope to inspire, educate and encourage these types of makers in their creative endeavors.
Usually this involves various physical media like metal, as in this case, wood, electronics, photography and other similar materials. If this sounds interesting to you, go ahead and subscribe and I’ll see you again in the next video.
Thanks for joining me on our creative journey.
Now, go make something. Perfection’s not required but fun is!
Histograms can be found in Photoshop for use in post-processing, not only on the back of our cameras when making the exposure. In this final episode of the Histogram series, Harley shows the different places histograms show up and what they represent within the image.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing"
by Kevin MacLeod at Incompetech
Sound effect: living-room-light-switch by alienxxx at FreeSound
Transcript
Histograms are an important tool when making an image in-camera. They also have their use during post-processing. In this episode of House of Hacks, I talk about how they work in Adobe’s Photoshop.
Hi Makers, Builders and Photographers. Harley here.
This is one in a series of videos about understanding and using the histogram. The others can be found in this playlist. I also have a playlist of other topics related to photography.
Today, we'll look at histograms in Photoshop. In this application, histograms tell us the same information as they do on the back of the camera but instead of just one histogram, Photoshop has several because of the different ways to view the image.
First off, if the histogram isn't visible, go to the Windows menu and select Histogram or you can click this icon.
By default it shows a little view like this. Click on this option drop down and select "All channels view" to see multiple histograms, one for each channel.
In many images all the channels will be very similar. But in some instances they might be quite different.
The split channels can be useful in situations where one color is predominant in your image. They help you see how adjustments to the image impact each color to help you know when one channel might start clipping, losing detail in the final image.
There's also this combo box that controls what is displayed in the top histogram. Personally, I like to show luminosity.
These histograms show the information for the image with all the adjustment layers applied. It’s the final histogram for the processed image.
As you turn adjustments on and off, you can see the histograms change accordingly.
Histograms also show up in some adjustment layers such as levels and curves.
The histograms that show in adjustments are the histogram for the image as that layer sees it, taking into consideration the original image and any layers below the current layer. This means adjustment layers above and below the current layer may have different histograms than the current layer.
As an example, this levels adjustment layer has a histogram for the original image.
If we make some adjustments and then add a curves adjustment above it, the curves layer shows a histogram based on the changes made by the levels adjustments.
If we make some adjustments on the curves layer, we can see the main histogram shows the results.
Also, if we make adjustments in a particular color channel, we can see how those changes impact that channel in the global histogram view.
If our adjustments are too extreme, we can see in the channel’s histogram that we start to lose details in this particular channel without the typical clipping showing in the main histogram curve.
In conclusion, I’d love to hear in the comments below about your experiences with the histogram, particularly during post-processing.
If this is your first time here at House of Hacks: Welcome. I’m glad you’re here. We’d love to have you subscribe. Through this channel I hope to inspire, educate and inform makers in their creative endeavors. Usually this involves various physical media like wood, metal, electronics, photographs and other similar materials. Thanks for joining me on our creative journey. So subscribe and I’ll see you again in the next video.
Now, go make something. It doesn’t have to be perfect, just have fun!
Grab a cold soda and look inside an early 90's vintage beverage vending machine as Harley tears down a drink dispenser found in the back corner of a warehouse. Beverage vending machines are basically refrigerated robots that we see everyday. In this episode, Harley takes apart a generic machine to see what’s inside, how it works and what parts might be scavenged.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing"
Incidental music: “Quasi Motion” and “Airport Lounge"
All by Kevin MacLeod at Incompetech
Sound effect: living-room-light-switch by alienxxx at FreeSound
Transcript
If you're squeamish about entrails, this video may not be for you.
Today at the House of Hacks, we're going to be dissecting this beverage machine.
[Music]
Hi Makers, Builders and Do-it-yourselfers.
Harley here.
Today we're going to roll up our sleeves... protect our hands from sharp edges... and actually do some work.
My employer had this vending machine back in the back corner of the warehouse and the boss wanted the warehouse cleared out. They told me if I could take it away, it was mine.
So of course I took it.
Nobody knows if it really works, it's been there longer than anybody else has been there. So we don't really know what I'm going to find when I get into this. Hopefully there's going to be some motors, maybe some relays, solenoids, other mechanical and electronic bits and bobs that I might be able to scavenge for the parts.
It also has a nice cabinet, pretty thick sheet metal. So we'll take a look at that and hopefully be able to use it for something.
I don't have a key for it so we're going to have to cut it open.
The way this lock works is there's this metal bezel. And there's this other metal insert part. When you turn the key, this metal insert part pops out and then you can turn the lock. There's a bolt that goes straight back here into the unit and that's what holds the door closed.
So, since I don't have the key, I'm going to have to cut the bolt.
This takes six different types of cans. They go in here. They roll down in a serpentine way down to the bottom where they get distributed.
So the walls are double wall construction. There's the outside heavy thick sheet metal. Then there's looks like some thinner sheet metal, galvanized, with insulation in the middle.
On the door unit, there's also an inside, insulated door that allows... keeps the cold inside and also gives a place in here for displaying product what's in each one of the units.
Down here at the bottom there's this shoot and above the shoot there's six motors with kind of a screw drive mechanism on it that allow it to release one thing at a time when the electronics tell it to go.
Down at the very bottom of this unit there's a refrigerator unit that looks really gunked up. Hopefully that motor's still good. Hopefully the compressor is still good because those can be used as either vacuum pumps or air pumps. But we won't be able to get to that until we take all the rest of this out.
So that's it for the overview of this particular unit. It's designed to work in conjunction with a snack machine that has the money changer in it and has all the control electronics with product selection switches and things like that. So this is just the mechanical side of things.
Tomorrow we'll get into actually taking everything apart.
Very good year!
OK, we're out here the next day since we ran into the sunset last night.
First thing I want to do is take off this inside door so I have a little bit more room to work with. There's just a couple screws top and bottom to do that.
Each product can have it's own price and all the available prices are printed on this strip. The strip is positioned as appropriate for the product setting by loosening the screws, adjusting the position of the strip and tightening the screws back down.
Now that I have the motors exposed, we can see a little bit better how this mechanism works for releasing product. The motors turn this plastic part here and when there's... two paddles offset from each other by 180 degrees. So the first one pops up like this and keeps the product from rolling out. When somebody makes an order, it then rotates so it's like this, there's a paddle behind that keeps the product from coming out more than one, and then this one is releasing just one.
So, it just kind of goes like this letting one product come in and then it just dispenses it. And there's a sensor switch here so it knows where it is in its circular rotation and there's another switch back in the back that tells when it's out of product.
OK, so it looks like this unit that allows the product to roll down and dispense, it looks like this is one unit that just kind of bolts in to the refrigerator portion. So there's a couple bolts top and bottom that I think is all that needs to do to release that and let it come forward.
These bolts are really corroded and so it's taking different combinations of different wrenches to try and get in there and loosen them up and get them out. But I think once I've done all that, this whole unit will just kind of slide out.
At least that's what I'm hoping.
So I've been really impressed by the way this thing is built. It's really modular. Just take out a couple bolts and it seems like things just kind of come apart. Unlike a lot of things that I take apart that are manufactured recently, I'm thinking automobiles specifically and electronics, that once it's put together you can't really take it apart; you kind of destroy it when you're disassembling it. This thing is really coming apart easily and I'm pretty impressed. I'm not sure they did that for assembly purposes or if it's designed to be highly maintainable. In any case, I'm really impressed with it.
So the way this unit is designed, I think this refrigeration unit will come out as a single module. I'm hoping all I have to do is remove some of these screws and it'll just slide right out. We'll see if we luck out.
We'll I think that's about all I'll do for this deconstruction at this point. I was originally going to take these inner walls out and give me an extra inch and a half on each side, I think, of space. But I think it's adding some rigidity to the unit and it gives me something to screw into if I want to build something inside this. So, for the moment I'm going to just leave it as is.
So let's go down to the basement and take a look at all the different bits and pieces that we have.
Well these are the major components: the outside shell with insulated sides, the inner insulated door, this product holder, a box of motor assemblies and miscellaneous screws and panels and finally the refrigeration unit.
I think I'm going to retrofit the outer box to use as a chemical cabinet. Right now paint and oil and other chemicals are stored in little spaces here and there around the basement. Having them all consolidated in one place would be really nice.
The rest of the items I'm going to tear down some more and put the materials in the raw materials storage for future projects.
I think this video is probably long enough as it is, so I'll do a follow up video where I tear down the motor assemblies and refrigeration unit. The control mechanism on the motors was a bit surprising to me so that'll be interesting to kind of tear down and take a look at in more depth. And the question of whether the compressor is good is still up in the air.
If this is your first time here at House of Hacks, Welcome! I'm glad you're here and would love to have you subscribe.
I believe everyone has a God-given creative spark. Sometimes this manifests through making things with a mechanical or technical bent. Through this channel I hope to inspired, educate and encourage these types of makers in their creative endeavors.
Usually this involves various physical media like wood, metal, electronics, photography, but sometimes it involves taking things apart to see how they work and get materials to recycle for future projects.
If this sounds interesting to you, go ahead and subscribe and I'll see you again in the next video.
The histogram is a powerful tool for the photographer. In this tutorial, Harley shows how to use this feature found on most cameras to quickly and easily setup lighting to isolate a subject on a pure white background. Properly done, a subject isolated on a white background is simple to cut out to composite into another image.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Incidental: "Sweeter Vermouth" by Kevin MacLeod at http://incompetech.com
Sound effect: living-room-light-switch by alienxxx at http://freesound.org
Transcript
Today at the House of Hacks, I’m going to talk about an impulse purchase I made several years ago that’s turned out to be one of the most used tools in my workshop.
[Intro]
Hi Makers, Builders and Do-it-yourselfers. Harley here.
A number of years ago I had an Amazon order that I needed to fill out to get free shipping on. So I ended up purchasing one of these inexpensive digital calipers. It was just an impulse purchase. I figured it’s cheap enough that if I never use it or I don’t like it, no great loss.
As it turned out, this little thing has… I use it on almost every project. It measures up to six inches and anything under six inches I’m pretty much using this to measure with.
It’s just really, really handy.
There’s a whole bunch of these on Amazon. This one I picked up for around 37 or so dollars. It’s one of the more expensive ones. I’ve seen them on, just searching before this video, I was searching and saw them for under ten dollars. They’re so inexpensive, I’ve seen people buy them new, cut them up to use the measuring device in things like jigs and things like that. So, they’re really inexpensive for whatever purpose you want to use them for. Like I said, I use them for almost every project whenever I need to measure things.
They’re great for measuring outside measurements using these big calipers. Using the smaller inside calipers you can measure inside measurements. And on the end you can measure depth.
They have a zero button on them so you can zero it out. You either close the jaws, zero it out and then you get an accurate measurement. Or, you can use it to get the difference between two measurements. Take one measurement, zero it out, take another measurement and that gives you the difference between the two sizes. That can be really handy.
And it’s also good for transferring distances. You can use the ends, they are sharp so you can scribe a little bit. Measure one thing and then use it to scribe.
It does have an on/off switch which doesn’t really work all that well. All it does is turn on and off the LCD display which really doesn’t draw much power. If you’re going to leave these sitting around unused for a week, you really should take the battery out and that’ll give you much longer battery life on it.
That said, the batteries are 357 button cells. Little things that you can get at Walmart, Target, places like that for a couple bucks a piece. They’re much cheaper on Amazon if you buy them in bulk. So I recommend buying them on Amazon because I think they’re less than a dollar a piece whereas the cheapest I’ve found locally is like a buck fifty, two bucks, something like that.
They have a units switch that switches between millimeters, inches as decimal and inches as fractions. So that can be handy depending on what it is you’re measuring and you’re comparing it to other things and what units you’re most comfortable with.
The device also came with a plastic carrying case. Just kind of inexpensive, but it does protect it. And inside it has a foam cutout for the calipers and two places for batteries. So if you’re carrying it around, that kind of protects it and keeps it from getting beat up.
A really, really handy device. I really recommend getting one.
So that’s it for today. I’ll leave a link down in the description for an affiliate link if you’re interested in helping support the channel.
Until next time, go make something. Perfection’s not required. Fun is!
In this House of Hacks episode, Harley presents a short overview review of the PEC Electronic Digital Calipers (Model: #8000-F06). These inexpensive digital calipers have turned out to be surprisingly useful around the home workshop.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Sound effect: living-room-light-switch by alienxxx at http://freesound.org
Transcript
Today at the House of Hacks, I’m going to talk about an impulse purchase I made several years ago that’s turned out to be one of the most used tools in my workshop.
[Intro]
Hi Makers, Builders and Do-it-yourselfers. Harley here.
A number of years ago I had an Amazon order that I needed to fill out to get free shipping on. So I ended up purchasing one of these inexpensive digital calipers. It was just an impulse purchase. I figured it’s cheap enough that if I never use it or I don’t like it, no great loss.
As it turned out, this little thing has… I use it on almost every project. It measures up to six inches and anything under six inches I’m pretty much using this to measure with.
It’s just really, really handy.
There’s a whole bunch of these on Amazon. This one I picked up for around 37 or so dollars. It’s one of the more expensive ones. I’ve seen them on, just searching before this video, I was searching and saw them for under ten dollars. They’re so inexpensive, I’ve seen people buy them new, cut them up to use the measuring device in things like jigs and things like that. So, they’re really inexpensive for whatever purpose you want to use them for. Like I said, I use them for almost every project whenever I need to measure things.
They’re great for measuring outside measurements using these big calipers. Using the smaller inside calipers you can measure inside measurements. And on the end you can measure depth.
They have a zero button on them so you can zero it out. You either close the jaws, zero it out and then you get an accurate measurement. Or, you can use it to get the difference between two measurements. Take one measurement, zero it out, take another measurement and that gives you the difference between the two sizes. That can be really handy.
And it’s also good for transferring distances. You can use the ends, they are sharp so you can scribe a little bit. Measure one thing and then use it to scribe.
It does have an on/off switch which doesn’t really work all that well. All it does is turn on and off the LCD display which really doesn’t draw much power. If you’re going to leave these sitting around unused for a week, you really should take the battery out and that’ll give you much longer battery life on it.
That said, the batteries are 357 button cells. Little things that you can get at Walmart, Target, places like that for a couple bucks a piece. They’re much cheaper on Amazon if you buy them in bulk. So I recommend buying them on Amazon because I think they’re less than a dollar a piece whereas the cheapest I’ve found locally is like a buck fifty, two bucks, something like that.
They have a units switch that switches between millimeters, inches as decimal and inches as fractions. So that can be handy depending on what it is you’re measuring and you’re comparing it to other things and what units you’re most comfortable with.
The device also came with a plastic carrying case. Just kind of inexpensive, but it does protect it. And inside it has a foam cutout for the calipers and two places for batteries. So if you’re carrying it around, that kind of protects it and keeps it from getting beat up.
A really, really handy device. I really recommend getting one.
So that’s it for today. I’ll leave a link down in the description for an affiliate link if you’re interested in helping support the channel.
Until next time, go make something. Perfection’s not required. Fun is!
Simply stated, Virtual machines (VMs) are computers inside computers. They are one of the best kept secrets in computers, particularly for consumers. Even people who have been involved with computer technology for a while can be intimidated by them but they are not that hard to use. In fact most web apps are harder to use than setting up a VM.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Sound effect: living-room-light-switch by alienxxx at http://freesound.org
Transcript
Want to run software for an operating system that’s not installed on your computer?
Want to have different computer configurations for different purposes?
Do you want to try out some software without the risk of installing it on your computer?
Virtual Machines are the answer to all these questions.
Virtual Machine software is really cool technology that can solve a variety of different problems but it can be a bit mysterious and intimidating if you haven’t used it before. Today at the House of Hacks, my aim is to remove that shroud of mystery and show how easy they are to use.
[Intro]
Hi Makers, Builders and Do-it-yourselfers. Harley here.
While virtual machine technology has been around since the 60s, in the late 90s a company called VMWare released software for PCs that pushed it onto mainstream commodity hardware.
Since then, that software has matured with many more features and additional companies have come into the market to give more choices.
Today I’m going to give a brief overview of
what is a virtual machine,
why use a virtual machine,
how does a virtual machine work,
what choices are there for virtual machine software,
what kind of system do you need to run virtual machines,
how to install VIrtualBox software,
how to create a virtual machine,
how to setup two simple VMs for Windows and Linux
and finally there’s a one question survey at the end.
That’s a lot to cover and if you want to skip to the next section, click up here or in the description below.
A virtual machine is a software package that creates another computer, a virtual computer, inside your real computer. There are a couple ways of doing this.
One way is to emulate the hardware.
Examples are Apple ][ emulators that allow you to run Apple ][ software on a PC. Another example is phone emulators that allow you to develop mobile applications on a PC.
In these cases, the virtual computer hardware is likely a completely different CPU architecture from your host computer.
This is not what I'm talking about today.
Another type of software falling into this category is software written to support a programming language.
In this case an abstract computer is defined and the software implements this particular computer.
Examples of this are the JVM for Java, the Perl virtual machine for Perl or the .NET runtime engine for .NET languages.
Again, this type of virtualization is not the topic for today.
For the purposes of this video, virtual machine software is software that partitions part of the real hardware and provides those resources to the software that's installed inside of it.
This virtual computer, or guest, is basically just like your real, or host, computer hardware.
The guest computer has its own memory, disks, video adapters and network ports that are inside, but separate from the host.
To the host computer it looks like any other application. To software inside the virtual computer, it looks just like any other real computer running any operating system you want.
Virtual machines are great whenever you want to isolate software from your computer or from other software.
One example might be on your home computer with kids. Create a virtual machine for their exclusive use and any changes they make will be isolated to their machine.
If they mess something up too bad, just restore their machine to a snapshot and it's back to a known state.
Another example might be you have a machine with one operating system on it and you want to run software designed for a different operating system.
Simply create a VM and install the other operating system in it to run that other software.
For example, I have a Mac with a Windows VM on it to run Windows Adobe products.
A final example might be in software development where you have one VM for back-end server development and a different VM for front-end client development.
Another use is to test software where you have multiple VMs setup with different operating systems and base dependencies for a product. You then save a snapshot of those setups and return to them at the start of each testing cycle.
You can even simulate a network of different computers all running inside a single host computer.
Virtual machine software provides an environment into which you can install an operating system.
The actual computer you install this software on is called the host. The virtual machines you create inside this software are called guests.
When you create a guest machine, you specify various aspects of its configuration.
The main ones are how much memory it should have, how many CPU cores to use, how large the disk is and networking options.
You want to set these to be less than what your real, host computer has. If they are set too high, the guest machine may take up too many resources from the host and slow things down.
Once you've created the guest machine you essentially have an empty computer ready to install an operating system into.
The guest does not have to have the same operating system as the host.
You can have different operating systems running on the same computer at the same time. This is really cool!
When you create a guest machine, its hard drive is stored inside a file on your host computer.
So you can move guests from one host computer to another or back it up by simply copying that one file.
It's also possible to setup a directory on your host computer as a shared file on the guest. This shows up as a drive in the guest and allows you to share files between the host and a guest.
If the same directory is shared between the host and multiple guests, then the guests effectively can see each others files.
However, the files that are stored on the guest's hard drive are only visible to that guest. Neither the host nor other guests can see those files.
There are many, many choices for VM software. There's a link in the description to a Wiki page with a huge number of them. In the PC world, there are three big names: VMWare, VirtualBox and Hyper-V.
VMWare was an early entrant in this space with a history going back to 1998. It has a huge number of different options and configurations.
They have many different software configurations to run virtual machines on anything from a single computer to managing a huge farm of machines in a data center environment.
Hyper-V is a product now owned by Microsoft and is at the core of their server management. Like VMWare, it allows running virtual machines on anything from a single PC to a data center.
VirtualBox started as an proprietary licensed product and eventually went open source. It was first acquired by Sun and subsequently Oracle when they bought Sun.
Its focus is on just the desktop and will run on Windows, Linux or Mac OS X operating systems.
VMWare and Hyper-V are large, flexible but complicated products. Their main focus is more on virtual server management in large data centers.
While they have products that run locally on a single computer, because of their focus on servers, in my experience they are more complicated to install and use.
Also, they are more limited in what operating systems they will run on.
I find VirtualBox to work perfect for my single user, non-server needs for both work and personal use. This is the software I will be demonstrating today.
The real, host computer needs to be reasonably powerful with an Intel or AMD processor. Most modern PCs fall into this category.
The two most important requirements for the host are memory and disk space.
At a minimum, you need to take the minimum memory requirements for the host operating system and add the minimum memory requirements of the guest operating system you want to run.
Of course with all things memory related, the more the better.
The disk needs to be able to store both the host operating system and any related software as well as any guest operating systems and their related software.
The VirtualBox software itself doesn’t need too much disk space, only a couple 10s of megabytes. However operating systems these days typically run into the 10s of gigabytes.
So plan on 10-50 gigabytes per guest machine in addition to the host’s needs.
To create a virtual machine, you first need to install the virtual machine software, VirtualBox in this example, on the host computer. Download VirtualBox from virtualbox.org for your operating system.
This installs just like any other software package: on Windows they have an exe file, on OS X they have a dmg file and on Linux they have different package formats for different distributions.
After downloading, start the installer appropriate for your machine. In this example, I’m on a MacBook Pro so I have a dmg file that’s mounted as a disk.
Double clicking the disk opens the installer. Double clicking again opens the pkg file and I can proceed through the typical installation process.
On a Windows machine, you will probably get a couple more prompts as it installs some low level drivers and disables network communications momentarily.
On a Linux machine, you’d use the package manager for your distribution to install the download.
Once installed, you click on the VirtualBox icon to start the VirtualBox manager. This is where you manage your virtual machines.
On the left is a list of all the guest machines you’ve created. Of course this starts out empty.
On the right is a panel that shows details about the selected VM. If you have multiple, related VMs, you can group them together to expand or collapse the group.
Across the top is a toolbar with common actions.
To create a new virtual machine, click the New button on the top of the toolbar. This wizard pops up.
First put in the name of the virtual machine. This name is what shows up the manager on the left side of the VM manager.
Then select the type and version of the operating system that will be installed. In this case, I’m selecting Windows. When ready, click Continue.
Next you need to select the amount of memory that should be used by the VM. The slider bar is colored to recommend values based on what the host system has.
You cannot allocate more than is installed on the host computer, so this maximum value will vary depending on your particular computer.
The host computer needs some memory for basic operations, so it’s recommended you stay in this green zone.
I tend to use no more than 50% of the maximum number. If you plan on running multiple VMs at the same time, you don’t want the combined memory usage of all the VMs to exceed the green part of this slider. Once the memory size is selected, click Continue.
Now the hard drive for the virtual machine needs to be configured. A disk in the guest computer is simply a file on the host, so the following wizard pages control this file.
The first page allows you to select the source of the file. The first option is if there shouldn’t be a disk. The second is to create a new disk. The third is to use an existing disk.
Generally I always want to use the default and create a new disk. The other options are for special situations and I rarely use them. Click Continue when ready.
On the next page the file format for the virtual hard drive is specified. The different options are for compatibility with other virtual machine software packages.
I always use the VDI format since I always use VirutalBox and don’t care about cross-compatibility. Click Continue to move to the next step.
This step allows you to select whether the hard drive should be dynamically or statically allocated. Dynamic allocation means it starts out small and grows only as needed. This option minimizes space on the host computer.
Fixed size means the hard drive is set to its maximum size when it’s created and does not grow any larger. This option may take a little longer to create but may operate faster. It will take a fixed amount of space on the host, so once it’s allocated, it won’t take up any more space.
Which option you use depends on how many virtual machines you will create and how much free disk space you have on the host computer.
I tend to have quite a few virtual machines so I select the default dynamic mode. This helps minimize disk usage on the host. When ready, click Continue.
The final step allows you to specify the name of the hard drive file name and its maximum size. The name defaults to be the same as was used in step 1 for the virtual machine itself.
The size value entered here is what is reported to the guest operating system as its disk size.
Remember those two options we just had in the previous step? This will be the maximum size of dynamic disk files or the size of the fixed disk file.
The size needs to be large enough to contain the operating system and any programs and data that will be put in it. But you don’t want it to be so large it takes all the disk away from the host computer.
Typically I set this to be in the 30 to 40 GB size range. When this is set to what you want, click Create.
The wizard will close and a new virtual machine shows up in the left side of the manager window. You now have a new, empty virtual machine.
With the machine selected in the manager, click the Settings button and you get a dialog that allows you to change many parameters of the machine and how it appears to the guest operating system. This has all the items from the wizard we just went through plus many other options.
Generally these don’t need to be changed from their defaults with one exception: the CD drive in the storage tab. This is used to install an operating system so the virtual machine is actually capable of doing something.
The virtual machine can use the physical CD drive in the host computer as its CD or any ISO file can be mounted without having to have a physical CD. I generally download ISO files and use them.
And now we get to install Windows. In this example, I select a Windows 10 installation ISO to put Windows 10 on my virtual machine.
I have licenses to all versions of Windows installation images via a Microsoft subscription service and can download these ISO files.
If you don’t have access to this, you can purchase a Windows installation disk and place it in the host computer’s drive. Then select the option to use the host’s CD drive.
Now that the VM is created and an installation disk attached to the CD drive, start the virtual machine by pressing the Start button in the toolbar.
A new window opens up containing the virtual machine. First you see a VirtualBox boot screen and then we see the Windows installation screen.
At this point we’re just walking through a standard Windows install procedure.
Select the values you want on each screen.
When it gets to the custom install/upgrade screen. There isn’t any information on the HD to be able to do an upgrade. If you select upgrade you’ll have to restart the installation process so be sure to choose the custom install.
The custom install allows you to partition the disk. In this case, the disk is actually the VM’s hard drive stored in the file indicated in the VM configuration. I just use the entire disk.
Depending on the installer, you may get a warning saying you are about to overwrite all the data on the disk.
This warning is always a bit disconcerting, but remember, we’re inside a virtual machine, so the only data we could lose is the data inside the blank file we just created.
And now we just wait for the installation process to finish.
When it’s all done, we now have Windows 10 running on our virtual machine and almost ready for use.
Let's shut it down just like any other computer.
Then remove the CD from the virtual machine by going back into settings and selecting the option to remove the mounted CD.
The guest operating system is installed and ready for use, but there’s one more step to help make it easier to use. Virtual Box has some drivers that can be installed that make the virtual machine nicer to use.
To install these, select the Devices menu for the Virtual Box application. On this menu, select the “Insert Guest Additions CD image…” option.
If the VM isn’t running, start it and then pull up Windows Explorer. Select the CD drive and then start the installer. Select all the default options and let it do its thing.
This software does many things to make the VM easier to use.
For example, it allows the clipboard to be shared between the host and guest operating systems,
it increases the options for different network configurations
and allows the guest operating system to resize to whatever size the window is set to rather than the fixed sizes based on common hardware configurations.
And that’s all there is to setting up a Windows virtual machine.
Next we move onto installing Linux.
We start with a freshly created virtual machine as described earlier. I select a Linux installation ISO I downloaded. All distributions I’ve seen have an ISO option to use for installation. This one is from Ubuntu.
Once the ISO is selected for the CD drive we’re ready to start the virtual machine from the toolbar.
A new window is shown with a VirtualBox boot screen. Shortly after that we see the start of the Linux install process.
Just go through the prompts as if installing on a real machine. The default values were appropriate for my situation but you can change them to something different if you need.
Similar to the Windows install, we get this warning indicating we’re going to overwrite the whole drive. This is OK since the whole drive in the context of a virtual machine is contained in the file created to contain the VMs hard drive. It’s not the physical hard drive of our computer.
Enter the user name you want to use and your password to login into the virtual machine. Or you can have it login automatically if you’d prefer.
Once all the setup information is given, it’s just a matter of waiting for the installation to finish.
When it’s all done, we now have Linux running on our virtual machine, almost ready for use.
Just like Windows, the first thing to do to improve usability is to install the guest additions. On the VirtualBox Device menu, select the “Insert Guest Additions CD image” option.
Ubuntu will detect the new disk and ask if you want to run the installer.
Other distributions may require you to mount the CD and/or run the installer manually.
In this case, I’m going to run it and enter the password to authorize the installation.
As mentioned before, this software does makes the VM easier to use.
For example, it allows the clipboard to be shared between the host and guest operating systems,
it increases the options for different network configurations
and allows the guest operating system to resize to whatever size the window is set to rather than the fixed sizes based on common hardware configurations.
When the Guest Additions are done, I reboot the system. In theory this isn’t really needed, but I do it out of habit.
Now the Linux virtual machine is ready for use.
And that's all there is to setting up virtual machines. Basically it's pretty easy.
I’d appreciate some feedback in this short, one question survey. Would you be interested in videos showing advanced features of virtual machines and how they can be used? Select an answer in the survey section above.
In conclusion, join me in the comments below; I’d be interested to know if you’ve used a VM before or not and, if you have, what you have used if for, or plan to use it for in the future.
If this is your first time here at House of Hacks: Welcome, I’m glad you’re here and would love to have you subscribe. I believe everyone has a God-given creative spark. Sometimes this manifests through making things with a mechanical or technical bent.
Through this channel I hope to inspire, educate and encourage these types of makers in their creative endeavors. Usually this involves various physical media like wood, metal, electronics, photography and other similar materials. If this sounds interesting to you, go ahead and subscribe and I’ll see you again in the next video.
Now, go make something. It doesn’t have to be perfect, just have fun!
Controlling appliances remotely can be useful, but some ready made solutions are pretty expensive. Today Harley shows an inexpensive way he uses to turn his shop vac on and off remotely. The same items could be used to control any appliance remotely.
The central part of this system is the PowerSwitch Tail. It contains an electronically controlled switch to turn things on an off. There are a large number of ways to control this. In this episode, we talk about a very easy way to use this device. In future episodes, we’ll expand on different ways to control this switch that can be useful around the shop environment.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Sound effect: living-room-light-switch by alienxxx at http://freesound.org
Transcript
In the comments of “How to quiet a shop vac”, Rob liked the low-voltage remote switch aspect of how I control the vacuum and he asked “Can you show me an example and material break-down that could easily then be added onto?”
Today at the House of Hacks, I will talk about that very thing.
[Music]
Hi Makers, Builders and Do-it-yourselfers. Harley here.
When I converted my shop vac to a central, plumbed in system, I wanted a way to easily start and stop it. I went through a couple designs before settling on the one I used. Today I’ll show a variation on my design that's an easy way of controlling a shop vac with a simple wired remote.
While my application is a shop vac, you could actually control anything using this technique. In the future I plan to show some upgrades to this control, but for now, I wanted to keep it really simple.
Before I start, I do want to point out that there are ready made solutions from expensive to cheap. I’ve not tried any of these to be able to make any specific recommendations but I did want to mention them for the sake of completeness.
If you just want to get the job done without hassling with making something yourself, you might want to investigate these. But if you want something that’s got your own style to it, you want to learn something, you need something that’s not available off-the-shelf or just want to have the joy of making something, hopefully the following will help.
At the core of how I made mine is a device called a PowerSwitch Tail. This is a short cord that looks very much like an extension cord. It has a plug on one end and an outlet on the other. What sets this apart from other extension cords is it has an electrically controlled switch built into it.
On the side of this box are two connectors. When these connectors have between 3 and 12 volts DC applied to them, the main power is turned on. When there is no voltage on the connectors, the main power is turned off. It only draws up to 30 milliamps, so it’s pretty easy to control with electronics, like an Arduino or other digital circuitry.
However, the easiest way to control this is simply with one or more batteries, a bit of wire and a switch. In this example, I’m using some D cells because that’s what I had lying around, but a 9 volt battery would be simpler and smaller.
To use it, just connect the negative side of the battery to the minus connector. Connect the positive side of the battery to one side of a switch and the other side of the switch to the plus connector. Now, when the switch is on, the device will be on and when the switch is off, the device will be off.
And that’s the easiest way I know to remote control a vacuum, or any device. The cost of the PowerSwitch Tail is around $30 and the wire and switch is based on what you want to use. You may have something in your junk drawer that could be used, like a USB cable or network cable that could have the ends cut off. Switches could be scavenged from dead electronics.
Or you could get new materials. Low voltage wire is a couple cents a foot at the home improvement stores and they have a wide variety of switches for a couple dollars each. A box to mount the switch in could be anything from a disposable food container to something more robust. Just use your imagination.
As I mentioned at the start, I do plan to do follow-up videos talking about different, more capable, although more complicated, ways to switch the PowerSwitch Tail on and off.
In conclusion, let’s have a conversation in the comments about buying off-the-shelf solutions versus making your own, or anything else you’re interested in.
If this is your first time here at House of Hacks: Welcome, I’m glad you’re here. We’d love to have you subscribe. I believe everyone has a God-given creative spark and through this channel I hope to inspire, educate and encourage makers in their creative endeavors. Usually this involves various physical media like wood, metal, electronics, photography and other similar materials. If this sounds interesting to you, go ahead and subscribe and I’ll see you again in the next video.
Thanks for joining me on our creative journey. Now, go make something. It doesn’t have to be perfect, just have fun!
Noise in photos can be a problem at higher ISOs, particularly in older cameras. In the episode, Harley talks about how shooting to the right of the histogram and then adjusting the exposure in post processing can help minimize noise. Topics covered include the reason this technique works, how to make the image in camera and how to adjust it in post-processing.
Special thanks to Rich Legg at Studio o2o for letting me use his remodeled lobby for the example shots. Studio o2o has great photography studios available for rent in the greater Salt Lake City, UT area. See their web page for more details.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Sound effect: living-room-light-switch by alienxxx at http://freesound.org
Transcript
Perhaps you’ve heard you should "shoot to the right."
What does this really mean?
And why should you think about doing it?
I'll try to answer these questions today at the House of Hacks.
[Music]
Hi Makers, Builders and Photographers. Harley here.
To "shoot to the right" refers to the right side of the histogram.
If you're unfamiliar with the histogram and how to use it, I have other episodes in this playlist where I talk about these topics.
In general, with an average scene, a proper exposure looks something like this one on the histogram.
The black side starts small, it increases through the grays and then drops off again approaching white.
The camera’s computer will try to make every scene fit somewhere in this curve.
The problem comes when you have large dark areas in your images.
These areas are more susceptible to having problems with noise coming from the sensor.
Here's an example of noise. See these odd blotches in what should be a smooth dark area?
Noise actually happens over the whole image, but it's mainly visible in the dark areas. Let’s see why.
Noise causes small random changes in the value the sensor detects for a given pixel.
Because the changes are small, and dark areas have small values, the noise is a greater percentage of the actual image data in the dark areas as compared to the lighter areas.
Just for the sake of argument, let’s say the noise is variations between plus and minus 10 values from the actual, ideal image pixel value.
Let’s say this area of the image ideally should have values around 20. When we add noise, a swing of 10 represents a change of 50% from ideal of 20.
If you have a two adjacent pixels that both ideally should be 20 but one has +10 noise and the other as -10 noise you end up with a 100% difference from the ideal between the two pixels.
Conversely, if we look at a bright area of the image where the values are around 200 a change of 10 represents only 5%, a much smaller relative change.
And so, because the noise represents a large percentage of the dark area’s values but only a small percentage in the bright area, it’s much more noticeable in those darker areas.
So what does this mean for the topic of “shoot to the right?"
The idea is that you should adjust your exposure compensation to shift the "ideal" exposure for gray to the right as much as possible but without clipping.
If you're in an automatic mode, you do this using the exposure compensation feature of your camera.
And if you're in manual mode, just simply adjust one or more legs of the exposure triangle to get what you want.
Use the histogram to determine when you have arrived at the correct point.
First, take a test image at what the camera says is the "correct" exposure and look at the histogram to see how much room you have.
Then dial the exposure compensation up to increase the exposure. The idea is to move the peak of the image to the right of the histogram.
Take another test image. And then repeat this process until the image is as bright as possible without clipping.
When you do this, the dark areas of the image move up into brighter areas where noise isn’t so much of an issue.
The problem now though is the dark areas will no longer be their proper dark color, they will be a washed-out grey. And the medium areas will be much too bright.
It just simply won't look right, but this can be fixed in post-processing.
Here's our image in Photoshop, a bit too bright since it was shot to the right. There are several ways of adjusting this.
The curves adjustment layer can be used to move that area that's too far to the right back into the center.
Just drag the black point at the bottom left of the curve over to the right but don't go so far that you start clipping your blacks.
You may also need to adjust the curve down to darken the overall image.
Another option is to use a levels adjustment layer to move the black point to the right, causing the overall exposure to be lowered and evening out the curve.
A third option is to use an exposure layer to simply lower the exposure.
Regardless of the method used, since the dark part of the image was captured outside the noise range, when the image is adjusted, the area the noise is in will be crushed and made much smaller, resulting in significantly less noise in the dark areas.
Here's the example scene shot with the exposure as the camera decides it should be.
And here it is shot to the right.
Finally, here's the shot to the right example with post processing.
Notice the difference in noise in the dark areas.
In conclusion, I’d love to hear in the comments if you have any opinions on using this technique. I know in some places it’s a bit controversial and in newer cameras noise is much less of a problem.
If this is your first time here at House of Hacks: Welcome. I’m glad you’re here. We’d love to have you subscribe.
Through these videos I hope to inspire, educate and inform makers in their creative endeavors.
Usually this involves various physical media like wood, metal, electronics, photographs and other similar types of materials.
Thanks for joining me on our creative journey. So subscribe and I’ll see you again in the next video.
Now, go make something. It doesn’t have to be perfect, just have fun!
The previous vacuum port design was less complicated than blast gates but still took a bit of work. Today Harley shows how to make a new and improved design that is much faster to make and easier to use.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Incidental: “Private Eye" by Kevin MacLeod at http://incompetech.com
Sound effects: living-room-light-switch by alienxxx at http://freesound.org
Transcript
In my video about “How to quiet a shop vac” I showed how I made hose connection ports modeled after a house central vac system. Today at the House of Hacks, I’m going to show a "new and improved” design that is simpler and faster to make.
[Music]
Hi Makers, Builders and Do-it-yourselfers. Harley here.
After making the first couple ports for my central vac shop system, I was perusing the plumbing department at the local home improvement store and saw these connectors.
They’re rubber couplers to go between two 2” rigid pipes with hose clamps on both sides. I realized they were the right diameter for the vacuum hose so I picked up a couple of them, along with some 45 degree connectors.
Back in the shop I cut a short piece of pipe and glued it into one side of the 45 degree elbow.
I attached the rubber connector to the other side and tightened the hose clamp down tight.
The other hose clamp I adjusted so the vacuum hose was a snug fit but could still be removed.
I trimmed the corners off a 4x4 and put it in the lathe.
Next I turned it into a tapered plug that fit into the coupler with a snug fit.
Finally I connected a chain to the plug so it wouldn’t wander off too far and get lost.
All told, I spent about 1 hour on this, including the trip to the home store. If you did an assembly line, you could make a bunch of these in pretty short order. This is by far much a much easier port to make than my previous design.
In conclusion, I’d love to hear in the comments about a time a designed of yours evolved over time.
If this is your first time here at House of Hacks: Welcome, I’m glad you’re here. We’d love to have you subscribe. I believe everyone has a God-given creative spark and through this channel I hope to inspire, educate and encourage makers in their creative endeavors. Usually this involves various physical media like wood, metal, electronics, photography and shop projects like this one. If this sounds interesting to you, go ahead and subscribe and I’ll see you again in the next video.
Thanks for joining me on our creative journey. Now, go make something. It doesn’t have to be perfect, just have fun!
Fluorescent tubes flicker because of their inherent design. LED lights may or may not flicker depending on how well their power supply is designed. How do you measure the amount of flicker? In this episode, we quantify the flicker in the fluorescent tubes and after an LED light conversion.
How to easily convert fluorescent tubes to LEDs: https://www.youtube.com/watch?v=_YROz2AekkA
Electronupdate video: Measuring Light Bulb Flicker with Nothing More Than a Cell Phone: https://www.youtube.com/watch?v=Qym5-126BDY
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Transcript
After seeing last week's episode about converting fluorescent lights to LEDs, David Terry asked "do they flicker the same way fluorescent tubes do?” I wasn’t sure, so let's measure and find out, today at the House of Hacks.
[Music]
Hi Makers, Builders and Do-it-yourselfers. Harley here.
Fluorescent tubes are powered by AC current and flicker based on the speed of the power cycles. Here in the United States, our power cycles at 60 hertz. This means the hot lead varies between positive voltage and negative voltage 60 times a second. The tubes don’t really care about positive or negative values, just the absolute value and so will flicker at twice that rate, or 120 times a second.
This is too fast to bother most people, but a non-trivial segment of the population are affected by this and have problems working under fluorescent lights. The flicker can also cause artifacts when shooting video at certain frame rates. And, as the bulbs age, they may not go on and off at every cycle, causing the flicker to slow down and become more noticeable.
To measure the flicker, I've got this simple setup. I have just a solar cell and the oscilloscope. The flicker in the lights will cause the output of the solar cell to oscillate in sync and the scope allows us to see that variation. At 120 times a second, we expect to see each cycle to be around 8 milliseconds so I have the scope set to 10 ms per division.
Now I'm going to connect the scope to the scope to the solar panel. And we’ll see what we have here… and that's exactly what we expect to see; each cycle is about 8 milliseconds.
So now I'll go over into the room other room and check it out with the LEDs.
I still have exactly the same setup as I had before. Let’s connect the scope to the solar panel and see what we get.
Ah, a straight line. So, to answer David’s question: no, there is no flicker with these LEDs. Thanks David for asking the question.
And coincidentally, a couple days ago an electronics channel I subscribe to, electronupdate, uploaded a video showing how you can use a cell phone to detect this flicker. I thought you might find that interesting.
If this is your first time here at House of Hacks: Welcome, I’m glad you’re here. We’d love to have you subscribe. Through this channel I hope to inspire, educate and inform makers in their creative endeavors. Usually this involves various physical media like wood, metal, electronics, photographs and other similar types of materials. If this sounds interesting to you, go ahead and subscribe and I’ll see you again in the next video.
Thanks for joining me on our creative journey. Now, go make something. It doesn’t have to be perfect, just have fun!
There are several ways to convert a fluorescent tube fixture to using LED lights. In this episode, Harley shows the fastest, easiest, but most expensive option to retrofit T8 and T12 fluorescent lights to LEDs. At the end, measurements are taken of the light output to see the effect of the new lights.
How to count in binary: https://www.youtube.com/watch?v=ZCFcuVHB1sI
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Transcript
Today at the House of Hacks we’re going to go from this to this. Oh, yeah!
Hi Makers, Builders and Do-it-yourselfers. Harley here.
The general illumination in my shop is all fluorescent lights and for quite some time now I’ve been wanting to upgrade them to LEDs. Recently I’ve had two bulbs that were kind of on the way of going out and today they just didn’t come on at all. So I went down to the home store and decided to bite the bullet and convert a couple of my fixtures, two of the fixtures, a total of four bulbs, from fluorescent to LED.
In all my investigation I’ve found that there are kind of three principal ways of doing this conversion: the first is very quick, very easy and expensive, the second is less expensive and also a little bit more work, and the third way is the most amount of work but also the least expensive. So, today, because of time pressure, I decided to go, on these, with the first option of the most expensive but the fastest and easiest to do.
For cost comparison, these bulbs are $60 apiece and I have four bulbs to replace. So that means the total cost on this conversion today was $240. Now to put it in perspective, I think I paid $200 for the whole fixtures originally, including fluorescent tubes. So it is quite a bit more expensive but now I have LED lighting with all the benefits thereof.
Today I want to look at what it takes to install them and what the difference is in the light output. So let’s get to it.
These come in four foot long packages. There’s two tubes that snap together to make an eight foot section. They’re made by Feit Electric, Feit electric, I don’t know how you really pronounce that. They replace both T8 and T12 bulbs and the advantage of these is they work off the ballast voltages so you have to do is take out the old bulb and replace it with the new one after you put everything together and unpackaged it.
It says it’s rated for up to 50,000 hours of life. We’ll see how that actually works itself out. It uses 44 watts and has a color temperature of 4100 Kelvin. So it’s sort of in the middle of the color temperature range.
Here we have one set of ends as packed. A cap is over one piece for shipping to cover the open middle where the two pieces will be joined together. It can be removed and discarded. And the other end contains the power pin that will connect to the light fixture.
Here’s the other set of ends. One end has a clear plastic piece over it that contains a magnet. This will stabilize the center of the light. Remove it for now and set it aside. This is the other pin that will connect to the light fixture. The other piece has a connector with two spring loaded pins. Pull this out until the pin locks into place.
Now slide the clear plastic support over the end without the connector but don’t cover the small hole for the locking pin. Slide the two pieces together until the pin locks into place. Finally slide the plastic piece over the joint to help support the connection.
We can see half the tube is aluminum extrusion to provide support and heat dissipation. The other half has a curved frosted diffuser.
Installation is just like a normal fluorescent tube. Once both ends are in place, push the middle up so the magnet sticks to the fixture for support.
And that’s really all there is to it. Snap the two pieces together, take out the old bulbs and put in the new bulbs. Short. Sweet. Simple.
I really like it. It seems to work out really well.
Now let’s go take a look at what the actual light output is.
The measurement of tubes is on the left and the LEDs on the right. There is 1 EV difference between the two. In photographic terms this is one stop, or twice the amount of light out of the LEDs.
So you can see, the light output from these is quite a bit more. It’ll be nice having consistent color temperature across all my bulbs too. Working in the shop should be much more pleasant for me.
If this is your first time here: Welcome! We're glad you’re here. All my videos have to do with maker related types of topics: woodworking, metal working, shop projects in general, kind of like this. If that kind of thing sounds interesting to you, go ahead and subscribe. We’d love to see you again in the next video.
Now, go make something. It doesn’t have to be perfect, just have fun!
This is the second in a series where Harley talks about histograms as they’re used in photography. Having problems getting a good exposure based on the preview image of your camera? In this episode we look at how to use the histogram to get the exposure you want for your images.
This episode looks at exposure as it relates to the histogram: what is "proper" exposure, how different types of images impact exposure and the histogram and finally how to see exposure problems on the histogram and what to do to correct them.
Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Light switch effect: http://freesound.org/people/AlienXXX/sounds/151347/
Transcript
Struggling to get the exposure you want? Today at the House of Hacks we’ll look at how you can use your camera’s histogram to get the perfect exposure.
Hi Makers, Builders and Photographers. Harley here.
The histogram is an important tool to understand the actual exposure of an image. When working with people in classes and workshops, I've noticed many of them look at the picture on the back of their camera trying to evaluate the exposure but don't have the histogram turned on. The problem is the image displayed on the back of the screen does not represent the actual exposure saved in the raw file. This preview is filtered based on several camera settings such as picture mode and white balance. Also, that screen is tiny and uncalibrated. It's really only a rough approximation of the actual image. Now don't get me wrong, the preview is a valuable tool; it’s great to see the overall composition. However, it's nearly useless to evaluate the exposure.
In this previous video, I explained what all the information on a histogram means. Today we'll look at the exposure as it relates to the histogram: what is "proper" exposure, how different types of images impact exposure and the histogram and finally how to see exposure problems on the histogram and what to do to correct them.
Somewhere in the history of photography, someone decided a "proper" exposure had a histogram that looks like this. It assumes that on average the majority of the luminance information is in the center of the image. Another way of saying this is that 50% gray will make up most of the image.
So, the exposure computers in cameras look for a peak in the image and try to adjust camera settings to put the peak in the center of the histogram. And this works well if you have an evenly lit, average subject. In an image like this, this rule works.
But this isn't necessarily valid for images that fall outside of average. And for artistic purposes, it’s not at all unusual to want something intentionally different.
For example, in low-key images, where a large percentage of the image is dark, this peak should be skewed to the dark side of the histogram on the left. But the exposure computer will try to push it to the center, making what should be dark, a washed out grey. This isn’t necessarily a bad thing, and in a future video I’ll talk about why you might want to intentionally do this. However, if you try to get the exposure correct right out of the camera, it doesn't give you what you really want.
Conversely, in high-key images, where a large percentage of the image is bright, the histogram should have the peak skewed to the right. But again, the computer will try to push it to the center, making what should be bright look dingy. Frequently you’ll encounter this problem shooting bright scenes outdoors, like at the beach or in the snow.
Unless the overall dynamic range of the scene is greater than your camera, generally both these problems can be fixed in post-production. However, both these problems are easily detected and corrected in-camera using the histogram. If you’re aware of the conditions you're shooting in and the look you're trying to achieve, you can know where the peak is supposed to be. Knowing where you want it, you can look at the histogram to know if it's in the correct spot or not.
If you find it’s not where you want it, and you’re using an automatic mode, use the exposure compensation setting on your camera. It allows you to tell the camera to adjust where the peak rests relative to center. By setting it to the plus side, you're telling it to move the peak to the right to brighten the image, or from the camera's perspective, you want to overexpose the image. By setting it to the minus side, you're telling it to move the peak to the left to darken the image, or, again from the camera's perspective, to underexpose the image.
If you’re in manual mode, simply adjust one of your exposure settings, f/stop, shutter speed or ISO, to make your image brighter or darker. If you're using your camera's exposure meter, the computer’s “perfect” exposure will be with the indicator right in the middle. If the image with this exposure is too dark for your scene, adjust your settings to move the indicator to the right. Or if the image is too bright, just move the indicator to the left.
Once these adjustments are made, make another image and re-evaluate the histogram. Repeat this process until the peak is where you really want it.
A significant problem in digital photography, that wasn't so much an issue with film, is clipping. With digital imaging, once a part of the image gets to a certain brightness level, it can't go any higher and is simply cut off. Everything brighter than that level is set to that maximum. It's clipped off. This causes a loss of information. The same type of thing happens in the dark regions. There's a level that means "black" and once that level is reached, anything less than that is set to black.
Imagine a number line that's really big in both directions. This is reality. But a digital sensor can only capture a region of this infinite line that has 256 values. Anything less than 0 is treated as 0 and anything greater than 255 is treated as 255. The number line is just cut-off, chopped, or clipped. Within a certain range, using exposure controls and ND filters, you can adjust where on the line this camera defines the start and end points, but you can’t change the size of the window.
Fortunately, clipping is easily detected by the histogram. If you have a tall vertical line on the extreme left or right edge, that image was clipped. If you see this, and you know you shouldn't based on your subject, you need to adjust your exposure either up or down, depending on which side of histogram the problem lies. Some cameras will flash areas of an image that are over and underexposed.
Just keep in mind, there are some cases where this can be expected to happen. A landscape image with the sun in it, or something with specular highlights, will probably have a small amount of clipping. This is normal and to be expected since these are the brightest areas of the photo. But if it's a wedding dress or white shirt, that's definitely a bad thing because any clipping will result in a loss of detail in these areas.
In conclusion, I’d love to hear in the comments below about how much you’ve actually used the histogram in the past. And, if you have used it, how it’s helped you.
Here are two playlists. One has all my photography related videos and the other contains other histogram related videos.
If this is your first time here at House of Hacks: Welcome. I’m glad you’re here. We’d love to have you subscribe. Through these videos I hope to inspire, educate and inform makers in their creative endeavors. Usually this involves various physical media like wood, metal, electronics, photography and other similar materials. Thanks for joining me on our creative journey. So subscribe and I’ll see you again in the next video.
Now, go make something. It doesn’t have to be perfect, just have fun!
