IowaDave Loc: North Iowa

I just purchased the 200-500 and I'm using it on a D7100. When i back button focus thru the viewfinder, the image looks like it is in focus but the image is out of focus and unusable. When i focus thru the LCD screen in live view the focus is fine. I don't like the delay in using the LCD and never used it before. I prefer using the viewfinder.
I'm shooting over 1/1000 shutter and using the VR. Handheld or tripod does not make any difference.

If i go into setting and work with the focus adjustment will it only effect the viewfinder or both viewfinder and live view focus.
any help is appreciated.
thanks

MT Shooter Loc: Montana

Have you adjusted your viewfinder diopter control to your eyesight?

orrie smith Loc: Kansas

do you have the same problem with other lenses? if so, it may be you need to set your diopter to your eyes. if not, have you tried to reset your camera to focus with half shutter instead of back button focus and compare the photos? if that works, something may be wrong with your bbf. fyi, there has been a recall on the 200-500 lens, but I do not think that is the reason for the recall, you may want to check with nikonusa and see what they have to say.

IowaDave Loc: North Iowa

yes, i have messed with it a lot. I did put my nikon 18-300 back on and it focused good.

I'm using spot focus with one focus point and continuous mode.

Do you think messing with the diopter would effect the autofocus?

mcveed Loc: Kelowna, British Columbia (between trips)

I am having difficulty understanding what your problem is. If you are using auto focus it shouldn't matter what you see or how in focus it looks. Put your camera on a tripod put your centre focus point on some detailed target, press the AF-ON button. The image should be in focus. Whether it looks to be in focus in the viewfinder or LCD should be irrelevant. If the image is not in focus you may have to adjust the auto focus fine tune. The AF system should get the subject in focus no matter what you see through the viewfinder.

orrie smith Loc: Kansas

Diopter will not effect the autofocus. If other lenses work with no problem, you may want to return the lens or send it in for repair

IowaDave Loc: North Iowa

I did a firmware update on the D7100 and I think this has fixed the issue. I feel like a DA for not doing that before i posted here. It's a grey and windy day here so i will test it more in better light.
thanks for everyone's input. I really respect the knowledge here on UHH.

orrie smith Loc: Kansas

No reason to feel dumb, that is why this post is here. Glad to see you have resolved your issue easily.

IowaDave Loc: North Iowa

just took this. hand held at 480mm, F7.1, ISO 800, and 1/2500.
the problem is fixed. Now i just need sun and practice.
Many Thanks again

(Download)

FiddleMaker Loc: Merrimac, MA

WOW !!! crystal clear. Excellent. even at ISO 800. So it was only a matter of firmware updates to your D7100. I have a D7000 - maybe I should check for updates. -FiddleMaker

jerryc41 Loc: Catskill Mts of NY

Unnecessary post since the problem is solved.

So the focus looks fine through the viewfinder, but not in the image. Yet it looks good on the LCD and also in the image. Other lenses don't produce these results? It seems that looking through the viewfinder messes up the focus. That's very strange.

I suspect everything is fine, but there's something you're doing to that affects focus. This sounds like the slit experiment in quantum mechanics. The results vary depending on whether you are looking through the viewfinder or not.

Put the camera on a tripod and take some random shots at different focal lengths, with a subject that will make focusing easy (not a clear blue sky, for example). Don't look through the VF or at the LCD. Just shoot some random images.

Another test. Shoot pictures looking through the VF and then shoot the same pics without looking. Please keep us informed about your progress solving this mystery.

Another idea - switch back to shutter button focus and use a remote or the timer to trip the shutter.

jerryc41 Loc: Catskill Mts of NY

Excellent! I'd love to know how updating the firmware could change that situation.

zigipha Loc: north nj

:thumbup:

amfoto1 Loc: San Jose, Calif. USA

Does your D7100 have a Micro Focus Adjustment feature? If so, you need to use it with that particular lens.

The viewfinder-based AF system is phase detection, using an array of individual sensors that are represented by the AF points you see in the VF.

LCD/Live View focus is contrast detection, using the imaging sensor itself. This is slower, but more accurate. In fact, it can be used to check and help you adjust the other focus mode.

Image focus accuracy actually has nothing to do with the diopter adjustment (so long as you aren't manually overriding the AF, based upon what you see in the VF). Adjusting the diopter only effects what you see in the VF, it does nothing to the AF.

All cameras and lenses are focus calibrated within certain tolerances. Often this is "good enough", but sometimes in needs fine tuning. For example, if a particular lens happens to be off a little one direction, while the camera is off a little the opposite direction, you're good because they cancel each other out. But if they are both "off" the same direction, that will compound the problem and can make for focusing problems just as you describe. It's exactly for this reason that manufacturers started including an MFA feature in their cameras, to allow users to fine tune focus accuracy. So, use the Micro Focus Adjustment feature as it's intended, to adjust that particular lens to that particular camera.

But, MFA can only do so much. It has it's limits. If the amount of adjustment needed is too much for MFA to handle, you may need to have the lens professionally calibrated (it might have slipped through quality control, gotten bumped during shipping, or just be a poor match for your particular camera). It is a clue that the 200-500mm may be out of calibration, since your other lenses seem to work fine. You may need to send the lens to Nikon for calibration.

However, there are other possibilities:

Do you have a "protection" filter on the lens? If so, try removing it and see if that helps. It is not unusual for a filter to cause issues... sometimes certain lenses just don't work well with filters, sometimes a filter will cause overall image softness, and sometimes they mess with AF accuracy.

Are you certain you are using the lens properly? Long telephotos are particularly challenging. They render shallow depth of field, which allows for little focus error. It could be that you need to use a different AF method than you are accustomed to using... which was okay with other lenses but isn't good enough with such a long tele.

Are you being overly-critical? A lot of people go straight to 100% viewing of their images on their computer monitors, which is like making a massive print and then viewing it from 18 or 20 inches away. If your images look good at 33% magnification, that's great. An actual print is nearly always sharper than what you see on a computer monitor.

There is a recall currently on the 200-500mm. I don't know the details or if it's something to do with focus accuracy. You might check the Nikon website for more info and to see if your particular lens is part of the recall.

MtnMan Loc: ID

Have you checked if your lens is included in the recall? I posted a recent thread with the link.

While a new lens should have the updated firmware you can't be sure. Nikon did not inform me of the recall so I presume they may not have informed all retailers who may have had some in stock. I only found out last week through UHH although the recall was last Sep/Oct. MT Shooter wasn't aware of it either.

My lens was affected and is in LA now for the firmware update.

The recall is for a firmware glitch that affects focus.