Fine Tune Autofocus: Could This Have Been the Culprit?

As I type this, I'm looking over a friend's D7100 because I was told the images were looking soft with a variety of lenses. I've seen the images and I had to agree, they looked soft. Long story short, I found the "Fine Tune Autofocus" setting had been tampered with on his camera. I don't use this feature and know very little about it, but the menu definitely had the Fine Tune option turned "ON" and one of the settings was maxed at "+20". I set everything back to "0" and turned the feature off entirely. A very quick and dirty test *appeared* to show much, much improved sharpness, at least when looking at the shots on the rear LCD (I can't download and look the shots on a PC right now).

From what I've described, could that single setting have been the cause of soft images for multiple lenses on this camera? I don't have my usual resources (aka "the manual") so I need some input, please.

Thanks!

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I would think so. Being slightly out of focus would make photos look soft in my opinion. So I would say yes!

I use that setting on my camera to fine tune lenses. If it was cranked all the way up like that then it ABSOLUTELY would have caused the issue for the lens it was programmed for.

The camera will store settings for 10 or 20, can't remember, different lenses. If the setting is on and there is a parameter adjustment set for that lens then it will make the adjustment. BUT, the setting is specific for a lens and not every lens that is put on the camera gets that adjustment.

Depending on the photos. Unless they all had shallow DOF, it seems something should have been in focus.

Glanced at the online manual and it does say that, wait, let me do this:

It's quite possible that all the lenses were set badly, if the user thought it was more of a sharpness control. So they set them all at +25 or something like that.

Thanks for your input everyone...

The settings on the D7100 in question, going by memory, were as follows:
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We were testing with my Sigma 50-150mm f/2.8 EX DC OS HSM APO (say THAT ten times fast) at 50mm, 100mm and 150mm all at f/4. Returning the settings back to zero and shutting the feature off entirely seems to have helped.

So you're saying, most likely, it's not my imagination that resetting this option should have helped?

Thanks again...

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I thought it was entirely lens specific, but the screen shot looks like you can set a default which would effect all lenses. So that very well might have been the problem.

The default is zero. It is lens specific. If the fine tuning is on, and it is a stored lens in the memory, it makes the adjustment.

I read it like [MENTION=4399]Rick M[/MENTION] did. The default value is used on any CPU lens that is attached that does not have a stored value.

So, if you attached a lens that you had not set up a specific value, it uses the default.

Thanks everyone... From what I can tell turning off the AF Fine Tune has solved the issue. Things are looking a lot better. I'll have a lot more time tomorrow to experiment with the D7100 in question to be sure.

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