- disassemble, reassemble with more baseline
- use mirrors to cause wider baseline
- subpixel trickery but that’s a tradeoff between Z resolution and XY resolution
- don’t image objects that far away, get them closer
for a given geometry, math puts a theoretical limit on things.
2 mm is tiny. that’s either not a stereo camera but an accident of design (was intended to be 0), or you’re dealing with something that’s supposed to be for microscopic applications, in which case 2 mm may be just perfect, relative to the intended object sizes and distances.