D800, FocusTune, 24-70 f/2.8, DAMMIT.

Started Nov 28, 2012 | Discussions thread
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PhotoKaz Contributing Member • Posts: 524
D800, FocusTune, 24-70 f/2.8, DAMMIT.

Purchased FocusTune, tested my 24-70 on the D800. This D800 has already been to Nikon to fix the left AF issue.

I tested a few things using the software, which is great to automate the analysis and take the guesswork out of this testing.

1. AF adjustment 24mm : Best at +20 but unknown if it should actually be higher than that. Even at +20 my best sharpness value is just under 17000 (not sure what units are used).

2. AF adjustment at 70m: Best at 0 and sharpness value at 38000. Image is MUCH sharper at 70mm.

So my lens is much sharper at 70mm than at 24mm. I'm not sure if that is the lens design or if I just can't go high enough on the AF fine tune to get a sharper image at 24mm. I suppose I can test this with some live view manual focus shots, and I may do that.

The problem is that there isn't a good AF fine tune setting for me at this point. 0 gives me best sharpness at 70mm, +20 best at 24mm. Setting to +10 just makes them both bad.

3. Aperture comparison, 24mm. Best at f/7.1 but fairly even from about f/5 to f/8. Stopping down the lens helps sharpness so shooting at f/5.6 is likely best bet for me.

4. Focus point comparison. I still have the left AF problem There is a huge difference in sharpness between the left AF points and the Center/Right/Top/Bottom.

Bottom line, lens and camera need to go back to Nikon. Joy.

 PhotoKaz's gear list:PhotoKaz's gear list
Sony RX100 Nikon D810 Nikon AF-S Nikkor 14-24mm f/2.8G ED Nikon AF-S Nikkor 24-70mm f/2.8G ED Nikon AF-S Micro-Nikkor 105mm f/2.8G IF-ED VR +3 more
Nikon D800
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