Honestly I'm not ready to send my lens to Nikon just yet. Having sent my D600 back 3x for the oil spot problem (and wound up getting a refund for the body), sending in a lens for a problem that was repaired but came back with a huge dust bunny inside the rear element causing the lens to go back a second time, and my SB-910 where batteries leaked (sent it out to them, too) and after using it twice for a total of 110 flashes before it failed, I am really hesitant to use their service. Plus we will be getting into the busiest time to ship packages. Definitely not thrilled to send anything until January. So I'm going to keep testing and experimenting for now.
I'm still trying to do everything possible to identify any issues with my 300mm f/4 PF lens. Yesterday I calibrated the lens numerous times with values that went from +1 up to +9 (and +9 was the one number that came up much more than the others). Today I went out in hopes of having more success.
Below are a few examples - but honestly there were some that turned out okay; however, the majority were still a little soft. So I might override the +9 manually and increase the value. Another thing I'm going to do is to cut through my Easy Cover (silicone cover for my D500) and expose the back button for my thumb to make direct contact. I've used these covers on every Nikon DSLR, but this D500 model doesn't make good contact with the back button. Even after exchanging it for a second Easy Cover...nope. When I contacted Easy Cover asking if anyone else was having trouble with the D500 cover, they said no. Sometimes the AF doesn't engage because of how the cover sits on that back button. It seems to require frequent adjusting to get it to make proper contact with the button.
This eagle image is cropped quite a bit and is a vertical crop from a horizontal image. There were really tall weeds right in front of me, and with the wind blowing, most of the images look as though I'm shooting through some type of thin material. At least this one gave me an idea of where I'm at since changing to +9 for AF tuning. It did require quite a bit of editing which I didn't used to do before this lens started having problems.
This next one was only edited in Camera RAW. It's slightly soft.
Below is the same image after taking it into the Nik Collection (Color EFEX Pro). Still couldn't achieve the quality that I usually get while editing with that plug-in because of the overall softness.
And here's yet another that just missed sharpness a little. However, it's definitely better than what I was getting before doing the AF tuning for lens calibration. In all honesty, I just didn't put much effort into this edit either since it missed focus a little bit. I will play with the AF tuning values to see if going higher has any benefit. One thing I noticed is seagulls that were very close and wouldn't have required cropping either were in focus or slightly soft. I would have thought that changing the AF tuning to +9 would have caused the focus on all close subjects to be compromised. When I did the AF tuning, I was at least 80 feet from my target - trying to replicate a real shooting situation. So it is surprising to notice that some close subjects were sharp.
Both lenses were pre-owned, but both worked fine when I received them.
