Patman99 wrote in post #15658148
So I joined in the S35 fray. I got one where it needs MA=+8 to focus well, so I'm torn as to whether or not to keep it, or try to return it in the 30-day window. I did shoot with it lot on Sunday in a mix of sunlight shining into a store, and also dealing with flourescent overhead lighting, and can't really determine if I had a focus-shift issue, I'll pore through the photos again and see if I can surmise that this S35 did better in natural light, and perhaps had a focus shift under flourescent light.
Here's a shot I took wide open at F/1.4 in natural daylight, hope it's not too risque, but it was pretty sharp for focusing at about 20 feet away at the young lass, and should have 2.3 feet of DOF in front of the subject, and 3 feet of DOF past the subject, so not too much bokeh going on in this shot. IMAGE LINK: http://www.flickr.com/photos/patcave/8513923114/ PS_24111
, on Flickr
I have just received my sig 35, and I know it is going back. It definitely has a focus shift issue. First, I have figured out the proper MFA for short distances. It was +5. At short distances images are great. Then I walked outside, and took a series of images, from a tripod, where the subject kept moving further, stopping, moving further, stopping. I see there is a significant backfocusing issue. When the subject is far, the focus goes even further.
Test your lens well, it will stay with you for long if you keep it, and if it does have issues, they will become evident time later, when it is too late to exchange it.
Also do the ruler test, to test for the focus shift with changing Aperture. This means, keep taking images of a mark on the ruler, and increase aperture. The field of focus will become bigger, but it should stay symmetrical on both sides through out the range. If it shifts as you increase the aperture, there may be an issue with the lens.
I am tired today. I will test the lens more tomorrow. But most likely mine is going back, and I am testing another one.
I had a feeling I should get two lenses at the same time, as I did with the sig 85. Got two, picket the better one, that worked good.