Locally Grown Caprese Salad

A project log for LadyBug BEEFY: 3D printer motorized microscope

Got printer? Connect to the motors with a Pi, plonk in a cheap scope, and do 2D and 3D scans!

ahron-wayneAhron Wayne 09/14/2020 at 16:120 Comments

A couple of days I was asked by a... farmer... to get some pictures of his (unripe) crop. I didn't do a whole lot of preparation: No special colored background, no specially create rig, didn't even fix it to the moving buildplate. Just took a lot of pictures and tried to post-process them into something good.

Once again there's not really a substitute for good input images, meaning: They should be crisp to begin with, the colors and exposures need to be consistent and not washed out, and the positions should not move in between stacks. Also this subject is really pretty hard to capture well, since it has so many spikes and folds that you could be doing a 4 mm Z stack on an image with a 1 MM field of view. 

50 images, single Z height, low magnification, stitched

500 images over 10 Z heights / 1mm step size with ~250 thrown away for having little information, stacked in picolay and then stitched.

A higher magnification zoom into the right of the (FOV 10x10 mm), 117 images at one Z height. Most of the image will appear to be not in focus at this zoom. But when they are, hey, look at those little bubbles of salad dressing! 

And then the same image but Z stacked --- 1900 images taken over 17 heights 0.2 mm apart, 900 or pics thrown away. I also played with the color a bit to look better and more realistic.

Finally, something presentable! And yet, the quality gain from stacking in less than ideal conditions rears its ugly head when you zoom way, way in, with huge blurring artifacts.  And that kind of defeats the point of using such a zoom lens --- the image only looks good when you look at it, like, at 3 megapixels. Better than the 0.3 MP the component pictures were, but not as good as the 25 MP the picture claims to be. You can compare this image with an unblurry part of the unstacked version and you'll see what I mean.  

I need to get a real camera.