Image quality issues

I have been shooting with the Sigma 150-600 sport for a month now and am having random IQ issues. Its not all the time but when it happens its bad. Any opinions as to its cause? I am shooting with the 7D mark II. Could it be the body acting up? I have read of AF issues with the 7D mark II. Here is one of the bad shots.

Heya,

Shooting over water with telephoto, no matter the camera, will do that sometimes. You'll find that water vapor + heat (even if it's not hot to you) produces a haze that makes AF very difficult, and also smears the image anyways.

Could also be your AF settings. I assume you have gotten razor sharp images and have calibrated that combination. But if you were holding servo for this, it's possible depending on the case and sensitivity settings on servo that you took an image while it was predicting and was only on partial focus while moving and tracking.

Very best,

I was thinking it was maybe heat/water vapor and yes I was using servo and using case 6

Yes those mirage effects will get you every time. What is worse is that the better the quality of the lens, the more mirage effect you will see!!! As well as photography I am a NRA (GB) rifle shooting instructor. When I did my course it was taught by the wind coach from one of the winning GB Palma teams (World Long Range Championships shots at between 800 and 1000 yards). He brought his spotting scope, a very nice Zeiss unit worth about £2500. This was in early March and the temp was under 10C at the time. You couldn't really see any mirage at all in any other scope, but through his Zeiss there was a very clear mirage running at 600 yards. At that distance you could make out every individual blade of grass, as well as making out the actual .308" bullet holes in the target. Most "normal" spotting scopes won't reliably resolve a bullet hole at 600 yards. This wasn't even over water, but was across what is effectively a normally relatively dry peat bog.

Alan

I know I have had trouble with it in the past shooting with my 100-400 however now shooting with this new 150-600 I am seeing it more often. Ive missed some nice shots because of it which sucks but I guess it is what it is. Im sure with the fall temp. changes here in MN. causing the sudden water to air temp. changes don't help either. Thanks for backing what I thought was the problem I just wanted too be sure my thinking made sense. The last thing I wanted to do was send the lens back for a problem it didn't have.

Judd S.