A guy I know (call him Albert) teaches middle school science and he's working on some lab guides for a new curriculum over the Summer. Part of what he's working with are simple "instruments" (e.g. low-power microscopes and telescopes and a few more unusual things like intraoral dentalscopes and borescopes) that are essentially repackaged CCD webcams. Nearly zero funding as usual, so I'm working on it out of curiosity between contracts.
Albert's big problem is that while these come with software it tends to be very special-purpose and limited in different ways such that each device needs a different application. So he wanted a new application built from scratch that would incorporate the features needed for all of these instruments in one program. That both makes student training easier and his lab guides simpler to write.
We've been at this for a few weeks now, and things have shaped up enough for him to work with the new program. This allows him to send me bug and feature requests to help refine it as Albert works on the hard part (the teaching stuff).
To make it easier for me to test my program I bought a number of these devices myself. These are at the low end of the spectrum, ranging in price from $5 to $40 on eBay and Amazon. CMOS sensors instead of CCDs. Lots of quirks like limited resolution, limited sensitivity, inadequate lighting, no auto- or remote focus, clunky stands and tripods, etc.
However you can always adapt real tripods or build custom mounts from wood, etc. With some fiddling the "stock" mounts are good enough for some things.
A sand sample under a $10 "microscope"
Lighting, mounting, and specimen preparation are tricky. The manual focus is also tricky and depth of field is limited making it critical. I might try using transparent tape to pick up a one-grain-thick sand sample to see if that helps. Maybe some different lighting instead of just the built in ring of cold-white LEDs aiming straight down will make a difference.
Leaves, bugs, fabrics, wood... all sorts of things look interesting close up.
I need to open up another $15 microscope I haven't played with yet. I expect about the same thing in a different package though.
I haven't done much with the telescope yet. Since it won't focus closer than about 100 meters I need to take it outside. That's up next, and I'm charging a neglected Win7 tablet so I can take the telescope out where I can get some views. Only 70x magnification (claimed) so no, this isn't for photographing the other side of the galaxy. It seems to have been meant for security and surveillance.
As I said, these are rock-bottom cheapie versions of "real" instruments. Both are 640x480 VGA. Both support Still pin capture, but that merely grabs a frame from the video Capture pin. Normally you don't bother implementing the Still pin unless the camera supports higher-resolution still images. Oh well. I'll have to take a look at the second microscope to see if it has better specs. The advertising copy for them all can be a bit misleading.
Too bad. I have a $10 webcam that can do still-snapshots up to 1600x1200. And even some modestly-priced current webcams without Still pin support can do 1920x1080 via the Capture pin.
Well, the school instruments are better even though not industrial-grade. They go up to 2560x2048, 5:4 instead of 4:3 aspect ratio the result is a squarer image.
Has anyone else played with this stuff?
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