- cross-posted to:
- cad@lemmy.world
- cross-posted to:
- cad@lemmy.world
I’ve managed to do reverse engineering of circuit boards using GIMP and rough alignment of layers using images like the one pictured. I want to use images to reverse engineer parts in CAD, but the minor lens distortion of a camera on a phone at ~20cm high on top of a stack of objects to keep it eyeballed flat is not enough. The result is off in multiple planes. There are minor errors in my curves in the transparent CAD part pictured, but the hole pattern is correct. The picture has been calibrated to 20mm against the ruler. Any suggestions on how to make this usable for replicating the ellipse that crosses the holes ±0.05mm?
To build if you’re doing this a lot and can’t use a brand lens with known correction data in darktable, set up graph paper and phone camera on a tripod to keep everything consistent, then photograph the empty paper. Create a transform in gimp to make the paper completely flat / square, and then just reapply that transform for every object you need to capture.