Thread Rating:
  • 1 Vote(s) - 1 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Sigma macro's AF inaccuracies call for new optic!
#17
OK, I've discovered some strange behaviour between the Sigma macro 150mm F2.8 non OS and my Nikon D750!

I had just made a home-made "Lens align" calibration gizmo and was testing the AF-S 50 F1.8......fine!

I tested the 150mm macro again to see what was going on with it.......we know that Sigma lenses do not communicate the full lens data to Nikon bodies....but while retesting I found that while recalibrating, every time the lens AFMF was changed the new setting the camera would make another profile in the lens repertoire.....after I had done a few settings, four profiles were listed in the repertoire for the same lens! I wiped three and continued shooting with just the one (and yes I do press the OK button to register the setting) Without doing anything other than turning on the camera......more profiles appeared......When the camera is turned on it sees the lens as another 150/2.8 lens and makes another profile.
Anyone of those settings might have been chosen by the camera and as a result the focus point was variable according to the which one of the four .......so that was what was happening, one minute it was choosing -10 the next zero!
That explains the lens's strange focusing behaviour, which started off well but with these impromptu profiles appearing unbeknown to me and the random choice of which profile it used, soon sent things downhill!
At the moment there are eight profiles and I must remember to check before shooting that it hasn't conjured up any more.

What a palava! eh JoJu?
Dave's clichés
  


Messages In This Thread
RE: Sigma macro's AF inaccuracies call for new optic! - by davidmanze - 03-16-2018, 04:24 PM

Forum Jump:


Users browsing this thread:
2 Guest(s)