Thanks @300ddr (Brian). I wonder if the one on Amazon suffers from the same problem as mine, where the holder is not rigid in azimuth because of the design. There is a bit of angular backlash, so when one adjusts focusing, the tip of the microscope rotates slightly, throwing the image out of view/focus until you release the knurled focusing knob at the end of the tube.
I recently bought a 3MP eyepiece camera for my optical scope and find getting the focusing and lighting right to be a challenge. Focusing is challenging because magnification is so great that the slightest touch causes the image to jump about. I was told by AmScope that the camera has an approximate magnification of 30X, yielding a 90X overall magnification with a 3X objective. Here is a shot taken with a 3X objective and the camera, resized to 800x600. The image is under-lit and rather washed out. I can adjust the contrast after the fact, as in the second image, but the image still doesn't compare with my cheap bad-ass 'scope.
I'm still considering adding a 140 LED ring light but am not sure whether it's going to solve the problem, or just add to the wash-out effect.
BTW, this is the same slider as in
this post after cleaning in an ultrasonic cleaner for about 90 seconds. I still have a lot to learn when it comes to cleaning sliders. I did learn not to brush against the normal direction of travel with a microbrush though, as that caused the slider to lift at its front, ruining the heads!