When I teach at UWM we’ve got this presentation camera at the front desk that can be used to show the Arduino and a breadboard and how things are connected. I believe it’s a Samsung SDP-860. It was probably awesome in its day, but the quality is not amazing. It does have a number of controls to zoom in and adjust the brightness, and has a built-in light and multiple outputs, but I still am not impressed with the image quality. When I did use it, I just connected it via USB to my MacBook and used QuickTime Player to get a video window and then showed that with the projector. It allowed students to see the tiny components I was using… so yeah, it worked.
But then I thought to myself, “Why not just use a webcam!?” and that’s what I’m going to do. Since I’m not teaching in the Spring semester I offered to do a Beginner Arduino Class at Milwaukee Makerspace, so I built my own camera thing… the Raster Presenter!
Yes, it’s basically a desktop microphone stand. There’s a long gooseneck to allow positioning the camera to point directly down at the desk. (It’s similar to the gooseneck rig used on Time Lapse Bot III.) I’m using a Logitech C910, which I’ve had for years, and which outputs some decent quality video.
The Raster Presenter is not quite as pretty as the Samsung model, but I dare say the quality is better, and it may even be more adjustable. It’s also lighter, can be disassembled, and does not require an external power supply. (Just a single USB connection!)
The camera mounts to a small piece of wood using zip ties that fit into notches. The wood slides into half of a mic holder that came with the mic stand. There’s a little bit of gaff tape to stop it from rotating on the gooseneck, and Bob’s your uncle!
When you launch QuickTime Player you just choose “File” and then “New Movie Recording” and you should see some live video. If it shows the computer’s built-in camera you can change it via the drop down menu.
After choosing the proper camera you can also choose to change the quality. I found that “Maximum” gave much better results than “High”, although it did seem to enable the auto-focus in the camera, which can occasionally be an issue (at least with other webcams I’ve used.)
Once you have all your settings you can move your mouse off the window and the controls (and title bar) should disappear. As long as you’re connected to a projector your students are ready to see the small things you want to show them! In the sample shot above the only light I used was daylight from the window to my left. I could see a bit of static in the image, but even in low-light it looked pretty good. I’ll do some testing to see if I can get away with existing light or need to augment it with another light source.
