My 2nd K-1 arrived a few days ago and I wasn't very happy with the camera's AF performance. In the past few days, I was busying testing and adjusting AF accuracy for most of my lenses -- they did accurately on my first K-1.
But I noticed another issue on this K-1, which I have seem before on K5, but didn't see on K5II and K5IIs: basically, camera back focuses quite a lot at portrait position and/or front focuses when camera is at landscape position.
I set camera single center point AF-S, aperture wide-open, shake reduction off, ISO 3200 to bring up shutter speed, mount camera on tripod or hand-held. I focused to the cover of the book standing vertical at the same hight at camera, which aligned to the long line between 16 and 17. Take a picture and turn the camera to vertical position, refocus and take another one. Repeat 5-7 times for each lens I have tested.
I tried FA43/1.9, DA55/1.4, and Sigma 85/1.4. All combinations have same issue: auto-focusing points in portrait position were significantly further away from camera than same setting shooting at landscaping position. To exclude the possibility of focusing target texture pattern affects AF accuracy, I also rotated the book and got same result. And the book cover gives enough sharp edge high contrast image to focus on
Anyone noticed similar problem before, on K1 and on other cameras?
here are two new photos I just took.
Last edited by grahame; 06-28-2016 at 06:40 PM.