Luminous Landscape Forum

Equipment & Techniques => Mirrorless Cameras => Topic started by: macz5024 on August 30, 2021, 08:05:18 am

Title: AF problem with Sony 24-70 mm 2.8 GM on Sony A1 - off most of the time
Post by: macz5024 on August 30, 2021, 08:05:18 am
After having replaced the A7r IV by the new A1 I am happy with the camera body, but not so happy with the behavior of the Sony GM-lens 24-70 mm/2.8. In low light or situations with relatively low contrast, the camera/lens is not able to focus properly. First we though it would be a problem at f8 and higher since the aperture does not seem to open for focussing at f8 and higher. However the problem occurs with lower aperture as well. I am using the selective focus point (S).
In order to have at least one sharp image, I am working with DMF and take one shot with AF and one wit manual adjustment. I have tested more than one of these lenses - always the same problem.
No such problems with other lenses (Sigma 14-24 mm, Sigma 85 mm). Does anybody else have this problem as well and what would be the best way for solving it. Thanks!
Title: Re: AF problem with Sony 24-70 mm 2.8 GM on Sony A1 - off most of the time
Post by: macz5024 on August 31, 2021, 04:33:40 pm
To be added: the problem occurs mainly at 24 mm. I have tested the Sony 24-105 mm on the same camera - no problem at all with this lens!
Title: Re: AF problem with Sony 24-70 mm 2.8 GM on Sony A1 - off most of the time
Post by: mshea on September 08, 2021, 10:34:37 pm
Iím required to do a lot of down and dirty headshots with either my a9 or my A7rIII, using the 24-70 at 70mm, usually at f/5.6 and occasionally at F/2.8.  Iíve gotten in the habit of checking focus every two or three frames after having to do a couple of reshoots. Focus is off in low or high contrast situations and at least 20% of the time.
Title: Re: AF problem with Sony 24-70 mm 2.8 GM on Sony A1 - off most of the time
Post by: kers on September 09, 2021, 03:18:38 am
Iím required to do a lot of down and dirty headshots with either my a9 or my A7rIII, using the 24-70 at 70mm, usually at f/5.6 and occasionally at F/2.8.  Iíve gotten in the habit of checking focus every two or three frames after having to do a couple of reshoots. Focus is off in low or high contrast situations and at least 20% of the time.
Is the eye focus not of any help in these cases?