For years I have been irritated by the lack of white-board space in the classrooms at the Art Institute. When the screen for the projector is pulled down, there is, literally, 4'x4' of white-board space available. As a result, I frequently have to erase drawings, equations, and bits of pseudo-code that I've written on the board. Almost invariably I want to refer back to... oops! It was erased!
Some of the classrooms at PSU have Lumens DC166 presentation cameras. My STAT551 teach uses the one in that classroom, and it's a pretty nice device. Joyous day! I figured I'd get one of those, and all my problems would be solved. I went to eBay to get one, but they're $200.
The hacker in me took over. When it gets down to it, the thing is really just a webcam and a light. It has some other features, like direct VGA / composite video output, but I don't need any of them because I have a laptop. I decided to build one. What did I build it from? Well, version 0.1 is a webcam and a light. Shocking, I know.
I used it this past Tuesday with Cheese. As you can see, the image quality isn't great. However, I was able to flip back to "erased" equations and drawings at will. Not only that, but I didn't get white-board marker smudges on my hands. The 0.1 test was a complete success.
I need to get a new cam, and I need to add a diffuser and a back "bounce" to the light. I also have some ideas for new software to write for it. I'll dish on that later. Once I get the final hardware built, I'll put up a full howto with pictures.
Even though I suspect you're being snarky, that's not a bad suggestion. There are a couple of practical problems with an overhead projector. I can't really multiplex one screen with an overhead projector and a laptop projector. I also don't think I'd be able to get overhead in the right position to project on the screen. Finally, overheads are much to big to stuff in my backpack.
Plus, I have some software ideas that I would not be able to do with an overhead.
Sorry, I realize that my previous comment really sounds sarcastic. I had never seen a "presentation camera" and was really stunned at seeing that a simple, well established device that even an elder person can operate such as the overhead projector could be replaced by an unnecessarily complex electronic device...
Overhead projectors do require a separate projection screen, so that multiplexing with the laptop projector can be avoided. If the lecture room does not support this, then I realize that everything you want to project must go through the laptop projector, and probably this presentation camera is the only option... But I would find it more sensible to upgrade the lecture room with an overhead projector and an additional screen!
Fair enough. Remember the initial problem: not enough white-board space. If I could get an additional screen, I could have probably also gotten another white-board!
This is a small school, and the programming classes are in computer labs (as opposed to traditional lecture halls). Unfortunately, there isn't a place for another white-board or another screen.
That said, your mention of using an overhead project has caused me to rethink my camera mount design. In one of the next versions I think I might try a configuration more similar to a traditional overhead.
This is awesome, Ian. A light and a webcam! Great idea.
At first I thought you were going to do Wiimote whiteboarding, but this seems a lot simpler.