Yeah, the little cylindrical 23mm tube cameras are pretty obviously only good for use with a monocular microscope, just to get an image on screen. But they are all USB 2, so can't do adequate frame rates except at lowest resolution. And there's no focus adjustment, and they don't have lenses to match the optics of eyepiece tubes, so they only see a small part of the available image.
That said, I wouldn't mind having a very cheap 2 to 5 MP one, for use with a small monocular microscope. Maybe later.
C-mount cameras are much more flexible, in terms of what they can be adapted and matched to.
On a purely speculative quest I bought a Waveshare Raspberry Pi camera, namely camera B:
http://www.waveshare.com/product/mini-pc/raspberry-pi/expansions/rpi-camera-b.htmThey have a few Rpi cameras, all based on the R-pi foundation original OV5647 sensor but the B model has an adjustable lens which can be hand adjusted and then secured with a grub screw, it is also a few dollars cheaper than the sanctioned camera. You can get from Waveshare directly or their ebay store and I think it is also sold on Amazon and dx.com. I only played with this for maybe 10 minutes and compared it to the the original Pi camera, before putting it away. My first impression is that it has promise, I want to build a stiff adjustable mount for it, but right now my lab is a mess and I'm backlogged for work.
Pro's: reasonable low latency HDMI output direct from Pi GPU to HDMI monitor.
lens much easier to focus than original R-pi
relatively inexpensive even when including an R-pi
module is small and light which means if you have a low profile mount you can get your hands or tools past it easily
Con's: Working distance is somewhat limited; going from memory about 10cm with approximately 10x mag(or more) and about 14 cm with 3-5x
I was holding the module in my hand and guestimating the distance whilst looking at the monitor, not very scientific
not ready made finished solution so yet another project (sigh)
R-pi boot time inhibition whenever you get an urge to look at something, something like 30 seconds
This post has prompted me to work on a jury rig mount so I can measure specs better.
R-pi video resolutions:
2592×1944 1-15fps, video or stills mode, Full sensor full FOV, default stills capture
1920×1080 1-30fps, video mode, 1080p30 cropped
1296×972 1-42fps, video mode, 4:3 aspect binned full FOV. Used for stills preview in raspistill.
1296×730 1-49fps, video mode, 16:9 aspect , binned, full FOV (width), used for 720p
640×480 42.1-60fps, video mode, up to VGAp60 binned
640×480 60.1-90fps, video mode, up to VGAp90 binned