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So I have a D7000. Grey market, which I didn't find out until after I had to send it in to get serviced. And it's never felt as...sharp as it should be. I always assumed it was just me. I am going on a trip soon and wanted a really nice mid range zoom lens. I picked up the very well reviewed Sigma 24-105mm F4. Went walking around town a bit, none of the pictures were in focus.

Finally fed up, I grabbed a Spyder test chart, did a few handheld shots and it seemed pretty obvious, to me at least, that my body was front-focusing pretty severely. Decided to get a little bit more scientific, set up my tripod and took a series of test shots. ALL of these are with the body set to +20, the max, in the AF Fine Tune. This album is the result. No post-processing beyond cropping. Thoughts?

https://www.flickr.com/photos/taylorhuston/albums/72157668721384795

I am also getting some weird color issues on my two primes, which I did not notice until just now, no idea what that's about.

EDIT: For a more 'real world' type of testing, I just walked around a bit and took some handheld shots of some things around the house. No cropping and I am set to single point auto focus, so the center of the image should be what's in focus. This is still with a +20 AF compensation dialed in for every lens.

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    How does this compare to focus obtained in live view? – mattdm May 22 '16 at 9:50
  • Also, do you have other lenses to try? – mattdm May 22 '16 at 10:03
  • Just those 5. Thought that was a decent cross section. – Taylor Huston May 22 '16 at 10:11
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    Five? Your question describes the Sigma 24-105mm. Please don't put important aspects of the question on external sites. – mattdm May 22 '16 at 14:45
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    Again, please include all relevant information in the question itself. Although getting a direct answer is important, you're getting free help, and it's best if your question is something that could be useful to others in the future. External links often vanish, plus they require people to jump through extra hoops. Please don't do that. – mattdm May 22 '16 at 19:56
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The images are obviously front focused. If it happens consistently with more lenses (not just one) then it is the body; if you can't compensate it enough with AF Fine (as it seems) you need to send in the camera for calibration...and hope it's not too expensive if your camera is not under warranty.

On the other hand, if it happens so heavily just with the new lens...send it back.

And just to do an additional test: try focusing with the live view and sees what happens.

Simple as it sound :-)

  • Yeah. That's what I assumed. Just wanted confirmation from someone else to convince me it wasn't just in my head. Just ordered a D7200. Amazon Credit Card, it's not real money right? – Taylor Huston May 22 '16 at 10:47
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    Lol. It's not real money, no ;-D But anyway...why not send it in for phase detection calibration? :-) – motoDrizzt May 22 '16 at 10:51
  • To who? It's grey market so Nikon USA won't touch it. The shady company I bought it from (through Newegg) has since gone out of business (sending it in for service when it stopped working ended up being a 6 month long process because of it). – Taylor Huston May 22 '16 at 11:10
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    Grey market just mean "no warranty". Nikon repair labs will still fix the camera, you'll just have to pay for it. At least, it worked this way for me with my Pentax and for many things I've owned. – motoDrizzt May 22 '16 at 11:16
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    @motoDrizzt Nikon has been known to refuse to service non-US products at their U.S. service centers. And no one else can get parts (other than battery doors and external rubber pads, etc.) from Nikon except for authorized Nikon service facilities. – Michael C May 22 '16 at 19:31
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If it is only one lens that you cannot get right with the autofocus fine tuning, there is an obscure trick to get around it. I didn't believe any of it when I first read about it, and I couldn't find anything about it on a Nikon site, but it worked. Please don't burn me before you try it yourself.

The default value for the fine tuning has a step size that is 2.5 times larger than the lens specific fine tuning, so you can get a value equivalent to 50 with it. I bought a second hand 20mm f2.8, but at home i found that the autofocus was way off. At -20 most of it was gone, but i was not quite there yet, i estimated I would need about -30. Very disappointed I stared to search the internet to find what my options were, and i found this trick. I started talking to myself out loud, and said 'no way this is going to work, sounds like complete nonsense', but i tried it anyway. Now it works fine with the default value at -12.

The disadvantages are that you can only do it for one lens, if you have more lenses that need more correction than 20 you need to manually change (and remember) the value every time. And you MUST set fine tune for every lens you have. If you borrow a lens, you must remember to set fine tune at 0 for it.

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