On Tue, Jan 05, 2021 at 11:17:47PM +0530, Sonali Warunjikar wrote: > Thanks. gimp's ellipse drawing tool with aspect ratio locked to 1:1 pretty > much does the same. The visual judgment of the circle matching (or its > bounding box being a tangent, but that gives fewer check points) has a 3 > to 4 pixels of variance when the experiment is repeated. It's seemingly in > acceptable limits given 1 pixel is 19 micrometer. Will try to average it > out.
Oh, this should have occurred to me before. Checked the headers of files produced by Windows s/w. They give a rock solid resolution figure across several x rays. Further, did the coin x ray on Windows to confirm that their distances reported by proprietary software are indeed correct. I think distance calibration is over. Now over to other image parameters.
