I bought this lens used (along with a bunch of others) and couldn't manage to get anything I felt was a viable image unless I stepped down to at least f5 (and even then it was adequate and nothing more). Assuming there might be something wrong with it (it was used, after all!), I sent it to Nikon service in Melville, NY (they've been great, btw). I received the lens and snapped a couple shots. No change.
To really make sure it isn't my imagination, I set my kit up on my Gitzo LS3540 and snapped these shots. Mirror lockup, IR remote release. I shot these in RAW, but exported them from Lightroom resized JPEG at 2000 pixels for the long edge. No other post-processing. All are at 100 ISO, single point focus.
First is wide open at f1.4 (1/50th)
Second is f2.2 (1/20th)
Third is f3.5 (1/8th)
Last is f5.6 (1/3rd)
Is it possible I just need to do some fine focus adjustments with this lens?
To me, the images are showing the effect of a de-centred lens element or misaligned mount - which is surprising given that Nikon have just inspected it.
The upper part of the cereal box appears obviously less sharp than the lower part, but the depth of field (certainly at f/5.6) ought to be enough to allow for the fact that the box isn't quite parallel to the sensor.
Other than sending this back immediately, what should my next course of action be? Are there other things I can do to determine if it's a lens/camera issue? I'd like to rule any other variables out before I send it back to Nikon (don't want a 'no problem found' response).
Fri 03-Feb-12 11:39 AM | edited Fri 03-Feb-12 11:43 AM by Luke_Miller
I had to use AF fine tune for my copy of this lens. It and the AF-D 85mm f1.4 would front focus on all three of my bodies (D300/D700/D3). These two lenses are the only ones that have ever required AF fine tune adjustments. Interestingly I did not have this problem with my previous D1 & D2 series bodies.
It will be easier to make AF fine tune adjustments if you get the target and sensor exactly parallel IMO. I think the variation in focus you are seeing with the box is because of its slightly out of parallel position.
>I had to use AF fine tune for my copy of this lens. >It will be easier to make AF fine tune adjustments if you get >the target and sensor exactly parallel IMO.
Will do - I'll post some shots later today. Any preference for a target, or is my box of Panko okay? ; )
Fabien, my first thoughts were to do what you described, however it's pretty apparent that it's not a back or front focus issue. Brian's observation of the off-center focus is what concerns me. Luke, was your focus issue a function of focus plane, or was it similar to what I'm experiencing?
The problem could be a misaligned camera sensor, but not if you are seeing the problem only with this lens.
I would repeat the test, making sure the cereal box is parallel to the sensor, and maybe add some shots at a longer distance, of a subject like a wall with some surface detail. Then send the lens with example image files and shooting details to Nikon.
AF fine tune is unlikely to help in this case - the problem looks like a lens fault rather than mis-focus.
>The upper part of the cereal box appears obviously less sharp >than the lower part, but the depth of field (certainly at >f/5.6) ought to be enough to allow for the fact that the box >isn't quite parallel to the sensor.
Huge improvements when I dialed it in, however my methods were merely to set up exactly as my test shots above were and dial AF Fine Tune in in -1 increments until focus improved. That, of course, happened at -20, the threshold for AF Fine Tune. This is the only lens in my arsenal giving me grief, and I just paid Nikon to service it. I'm going to try and test it on my friend's D300 body. If it's not an issue with his camera, I'll chalk it up to bad juju and live with -20 correction, as it appears serviceable enough. If the lens does something similar on his body, I'm calling Nikon. I'm sure they'll rectify it if there's a problem.
Well, there's got to be something going on betwixt my body and this lens. My friend's D300 had no issues with this lens on it, whatsoever. Rather than beleaguer the point, he offered to swap me his Nikon 50mm f1.8 for mine, which works swell on my camera. Much cheaper lens, but a working lens is better than one that isn't, and I'm pretty sure I can live without f1.4.
Not really the right solution, but a workaround, for sure. I'm going to set up a test tomorrow and put all my lenses through the wringer just to make certain that there's no issue with the body.
I've decided that the camera body is going in to Nikon service. It's just not sitting right with me that I can't use this lens, and after setting up the same test and trying my 85mm f1.8 and 24mm f.2.8 with slight out of focus results. Not horrible, mind you, but still not great. In fact, if I hadn't seen the test shots we took with my friend's D300 I would've just assumed that my results were what I should expect. However, his were commensurately better, even wide open!
I'm probably just being paranoid, but I can't help but feeling the best course of action is to nip this in the bud early.
Nikon service found an issue with the AF system in my D7000. I sent both the body and this lens to them, and they confirmed two things: 1. The AF system needed service. 2. There was no problem with the lens.
I scratching like mad to get them back! Should be here late this week or so. I'll try and post a test shot after I get them back. So happy I got this taken care of - makes me feel better to know that my technique isn't the only problem! ; )