After fumbling with the software it’s now time to have a look at the optics and its performance.
As I wrote above I’m using a cheap lens with a focal lenght of 16 mm at f/2.0, according to the description on amazon. On the lens it says: 16 mm, 5MP, 1/2.5", IR. The M12 thread has a lenght of 12 mm with a backfocus of 4 mm.
The M12 mount which I printed has a thread with usable height of about 10 mm.
With this lens at the uppermost position of the focuser with minimum magnification I get a FOV of 36 mm x 27 mm with a flat object. The distance of the front of the lens to the object is 155 mm.
On the 7" display the object is shown in a picture 120 mm wide with a magnification of about 3.3x
resulting in a resolution of about 45 μm / pixel.
The maximum magnification with the lens unscrewed as far as possible can be achieved at a distance of about 30 mm. The FOV is about 6.1 x 4.6 mm resulting in a resolution of about 8 μm / pixel at a magnification of about 20x on the screen! About 50 % is in focus.
Of course all the above results regarding magnification and resolution are purely calculative and just for comparison to get an impression of the possibilities of this microscope.
All in all it’s not that bad considering the 10$ lens I used. I will try and find a better one, also with a bit longer focal lenght.
It’s a bit shaky to get correct focus, because you have to set it on the lens rather than using the focuser, especially with higher magnifications. I will have to better lubricate the moving parts.