What is your process for critiquing your own photos? I have been thinking about selling them and I want to put out a great photo. Yes, photography like other art forms, is highly subjective but how do you not fall into the trap of not seeing the flaws in your work. For example, I have worked on photos to get them where I like them but when put out for critiques, they get ripped apart on things I did not see or seemed on par with other well liked images. I am working on getting better but still need work.

I have been noticing some focusing issues with the above combination of body and lens that hasn't happened in the past. I have had the camera for a bit under 2 years and the lens for 18 months and never had any problems. In fact, one of my magazine photo editors commented in October how extremely sharp some recent pictures were with this setup.

Over the past 6 weeks or so I have noticed some shots that should have been tack sharp being a bit blurred. Another odd thing that happened twice in that time is that the focus in live view would not work. I would press the shutter to focus and nothing happened. I turned the camera off and back on to no avail. Removing and replacing the battery also did nothing. Finally, by removing and reattaching the lens it went back to normal.

On Christmas Eve I was taking a shot of my tree lit up at night, at ISO 64, F/8, and a 4s exposure. I was disappointed to see that the picture was blurry. I tried a few more and finally one came out sharp. I took exactly the same picture last Christmas, with the only difference that I shot at F/7.1, and every shot was absolutely crisp.

Being the chemist that I am, I started taking a lot of shots to examine different variables that might be causing this issue. Here is a short summary of my experiments from today.

1. The problem seems to disappear if I shoot at F/5.6. At F/8 or higher it's back. I actually started watching the focusing distance scale on the lens and suddenly realized that the lens was not focusing correctly. At F/8 and about 8 ft away it might focus at infinity one time, clear past infinity another, and occasionally right where it was supposed to be. All of my shots today were at exposures of 1 to 2 seconds.

2. The issue seems to happen only when I move the focus box to the side of the frame. When it's in the center there's no problem, but at the side (perhaps 1/4 of the way from the edge of the frame), the focus is way off, usually infinity. The focus box still turns green, indicating a focus lock.

3. I almost always shoot in live view, because focusing is supposed to be a bit better and I can move the focus point anywhere in the frame. But for the heck of it, I decided to compare results using the viewfinder to focus vs live view. Much to my surprise, using the viewfinder the focus was fine no matter what I did. On the edge or center of the frame, F/5.6 or F/11, no problem. I toggled back and forth between live view and the viewfinder and live view continued to fail at the edge or at smaller apertures.

4. I did a comparison test with my Nikon 14-24 F/2.8 using all of the same settings and it worked fine with either focus mode.

5. I tried both lenses on my D750 and got the same results as with the D850.

6. I tried the 24-70 with VR both on and off, with no differences noted.

7. I went outside where I could shoot at faster speeds, this time at 1/30 and F/11. When focusing at the side of the frame using live view, the focus jumped all over. I depressed the shutter several times to refocus and it kept coming out different. One time at beyond infinity and the next at 6 ft. Switching to the viewfinder there were no problems. Also, when I shot at F/5.6 and 7.1 the problem went away as well. Also, when I switched to the 14-24 everything was fine again.

I haven't called Nikon yet, as my past experiences with the tech support staff has been useless. It is clear that they know little about the equipment other than what they can read on a computer prompt, so I thought I would go to the experts at the hog and see if anyone else has observed this problem. Thanks.

Phil