(1971) Close-range Camera Calibration Symposium on Close-Range Photogrammetry, Urbana, Illinois, January 1971. Brown seems to have single-handedly reverse-engineered every camera ever invented while precisely measuring parabolic antennae during the 1960s.īrown, D.C. Self-calibrating bundle adjustmentĮarlier in the week I added extra info I found about the history of photogrammetry which I think is fascinating.ĭuane C. Negative results are informative, but reaching this one involved unnecessary complexity which was difficult to communicate clearly, so discarding the work was a relief. I think I only did it because 4 potential scale factors may be calculated from the data but only one can be applied, so it seemed somehow logical to calculate a mean from those 4 values… to create 1 scale factor from the 4. But if I have to calculate 4 anyway, what’s the point of a 5th which will only ever provide a second-place result? I thought it might be useful because it was the second most accurate PSF 19 out of 26 times. I had hypothesised that a mean of the potential scale factors, which can be generated from the 4 spans measured for each mesh/form, might be useful, but it isn’t really.įor every bird, the mean of the 4 PSFs was trumped by one of the directly calculated PSFs for accuracy… so the extra calculation didn’t serve any useful purpose. Today I changed the scope of the results to make the data set and treatment simpler. The Report is submitted… again! I’ve submitted it several times this week and then noticed some issue which needed changing.