Upload & Sell: Off
| p.4 #8 · Sigma 35mm f/1.4 AF problems |
Here are my results on the D800, comparing the center and rightmost AF points at AF tune values of 0, -10, and -15. Focus distance was 3'4", measured from subject to focal plane indicator on body. Lighting was tungsten (2350+5 in LR4). I took 5 shots at each AF tune value, to eliminate shot-to-shot variability, with focus racked between each shot. Tripod, MLUP/exposure delay, raw, all processed identically in LR4. Results indicate an AF tune delta of at least 15 between center and rightmost AF points.
EDIT: Ran the test on my D3s as well:
Here are the results of a Canon copy of the Sigma on a 5D classic (no AF tune available on body):
Thanks for your diligent work. You've been much more thorough than I was in my testing, but my results were SO obvious and so repeatable, that I didnt feel that I needed thorough testing on my copy to know that it had problems. It looks like the 5D doesn't display any issues at all then. This is not that surprising- focus systems across platforms and cameras are implemented completely differently.