DIY Stack and Stitch System

mawyatt2002 wrote:

Entropy512 wrote:

Nice!

Trinamic stepper drivers have become extremely popular with the 3D printing community.

FYI a similar project hit Hackaday a few days ago - https://hackaday.com/2019/06/14/gigapixel-microscope-reveals-tiny-parts-of-the-big-picture/

Thanks.

The project over on Hackaday is very interesting, great for starters to get involved and seems straight forward.

The wood platforms and the linear rails used will need to yield to higher levels of precision, stability, and repeatability to get close to the resolutions mentioned. Most folks in higher precision and resolution stacking use precision rails and microscope objectives. Also it's usually better to move the camera/lens/subject in the Z axis rather than the usual in camera focus when you move to higher magnifications beyond ~2X for the best IQ. So not only the mechanical, electromechanical and electronics, but the optics can get quite involved. With stacking and stitching then telecentric optics become an important factor for consideration if subject distortion is important.

That appears to be the approach he's using for focus - "The focus was adjusted with the tripod z-direction." - but obviously that wemacro setup looks like it would be much better.  I'm likely going to get one if only for film copying purposes.  Using a tripod kinda sucks for this sort of purpose. 

The HaD guy's approach to telecentricity appears to be to add an additional aperture stop between the main lens and the reversed one in his setup.  I'm not sure what the validity of this approach actually is - but it's something I never tried and might explain why I had many weird issues when putting a reversed 28mm lens on a 100mm lens.

Some of the commercial offerings from Wemacro and Stackshot are pretty good for those that don't want to DIY for Z axis stacking, but for very high precision work you'll need to move to the industrial type rails.

You appear to be operating at much higher magnifications than the guy on HaD - but you've got a system that can handle some of those really extreme scenarios without costing much more from what I can see.