D7100 focus problems

guillermo_arp

Senior Member
My Nikon D7100 is focusing aprox 0.5cm in front of my subject.

I've made the same test with 3 lenses:

35mm 1.8 DX
50mm 1.4 AF-D
28mm 2.8 Ai-S

It came clear with the Ai-S. This lens has a beautiful focus ring, precise and smooth, by using manual focus and the electronic range finder I can see how the dot (o) appears even though proper focus has not been achieved as I can see trough the viewfinder. The resulting image is obviously not in focus. The same thing happens with the other lenses. AF fine tune does not seem to work.

Is there a way to fix this? Do I have to send my camera to have this checked with an expert (ex Nikon Service)? If so, can they fix it without replacing parts?

I'll appreciate any information.
 

SpikeyLemon

Senior Member
Sorry, I read the whole thing again... And questions for OP

If you trust the rangefinder dot and take a picture even your viewfinder is showing out of focus, is that also out of focus on the JPG file?
If no, then check the diopter adjustments on the viewfinder.
If yes then AF fine tuning or some kind of calibration might be needed.

Just curious, how did you conclude the AF fine tune didn't work? Did you set up target, tripod and tried the whole range to establish which number of tune for your lens?
 

guillermo_arp

Senior Member
For this test I shot a book and the camera on a tripod. I was shooting at a specific line aprox 2 feet away, using the widest aperture available.

If you trust the rangefinder dot and take a picture even your viewfinder is showing out of focus, is that also out of focus on the JPG file?
Yes, when I look at the photo full size on the LCD is obiously out of focus.


Just curious, how did you conclude the AF fine tune didn't work? Did you set up target, tripod and tried the whole range to establish which number of tune for your lens?

AF-Fine tune does not work since no matter what value I set, it keeps focusing 1cm too close to the camera. For example, if I set a value of +5 or +20 with the 35mm, it keeps focusing on the same spot.

:confused:
 
You really need to go about Fine Tune in a more organized manner to get it to work correctly. If you really can't get it set correctly then I would suggest getting FoCal Pro it walks you through all the steps and lets the computer decide the best focus point.
 

guillermo_arp

Senior Member
You really need to go about Fine Tune in a more organized manner to get it to work correctly. If you really can't get it set correctly then I would suggest getting FoCal Pro it walks you through all the steps and lets the computer decide the best focus point.

Looks expensive but I'll have to give it a try. Two questions, does FoCal Pro actually fixes focus issues by means of software? Or it only tells me if my camera has an issue and how bad it is...
 

SpikeyLemon

Senior Member
Photography can be an expensive hobby. :)

You can also try Dot-Tune. Search for it on YouTube for this one. Make sure you follow the instructions to the dot. (Yeh, I know.) the hardest part for this one is to find a suitable target to print out, after that is very straightforward.
 
Looks expensive but I'll have to give it a try. Two questions, does FoCal Pro actually fixes focus issues by means of software? Or it only tells me if my camera has an issue and how bad it is...


It does not Fix things. What is does is guide you through the find tune process and when you get through the process the lens should be in tune. There is a focus chart file that is with the program that you will print out and use in the process. If you do go with this program make sure you print the chart on good paper. I used a photo quality matte finish paper and it works great. Go to a place like Office Depot and get some of the foam core board that is sticky on one side and mount the print on it and then trim to size. Make sure you have good light and that everything is squared away a close as possible. All of these things are the same as if you were trying to do it by eye. The standard thinking is that you should be fine tuning at 50 times the focal length of the lens. For your 50mm you should be tuning it at 98.425 inches or close to it. I generally round it up to something close like 8 feet in this case.

I was having all sorts of problems getting my shots in nice sharp focus and I tried all sorts of tuning methods until I went with FoCal
 

mikeee

Senior Member
What is the rated focus distance of each of those len's? 2 feet away might be too close.
I thought the 35mm and 50mm were minimum of 2.5 feet.
 

mikeee

Senior Member
Do you upload the photos and see out of focus too? It's not something simple like the eye piece diopter being out of focus?
 

guillermo_arp

Senior Member
It does not Fix things. What is does is guide you through the find tune process and when you get through the process the lens should be in tune. There is a focus chart file that is with the program that you will print out and use in the process....
I was having all sorts of problems getting my shots in nice sharp focus and I tried all sorts of tuning methods until I went with FoCal

One thing, correct me if I'm wrong, but fine tunning is for autofocus only, with my other lens, the 28 Ai-s, the camera does not allow me to fine tune it. Do you thing FoCal will work in this case? With the 28mm Ai-s I get the same result: it focus aprox 1cm too close. The rangefinder tells me that is in focus buy when I look at the photo in the LCD its obviously not in focus.

Do you upload the photos and see out of focus too? It's not something simple like the eye piece diopter being out of focus?

Not a chance since I'm using AF and the rangefinder marks on manual focus.

I'll Upload a few photos shortly.
 

Marcel

Happily retired
Staff member
Super Mod
There is a slight chance of the camera's focusing ground glass is out of adjustment. If you don't look at the little focusing dots and rely on the image you see in the viewfinder, does the sensor's capture (LiveView) match the focus you see on the ground glass?

One more thing. When (with some lenses) you focus at full aperture, do you then take the shot with a smaller aperture? Some lenses do have what we call focus shift with different apertures or when you focus and then reframe.

I hope you find a solution that fits you on your own. Otherwise, send the camera in to Nikon for a focus calibration check.

Keep us informed.
 
One thing, correct me if I'm wrong, but fine tunning is for autofocus only, with my other lens, the 28 Ai-s, the camera does not allow me to fine tune it. Do you thing FoCal will work in this case? With the 28mm Ai-s I get the same result: it focus aprox 1cm too close. The rangefinder tells me that is in focus buy when I look at the photo in the LCD its obviously not in focus.



Not a chance since I'm using AF and the rangefinder marks on manual focus.

I'll Upload a few photos shortly.

FoCal is just for autofocus


Sent from my iPhone using Tapatalk
 

guillermo_arp

Senior Member
Ok this is weird... I rarely use live view, actuall I never use live view. I performed a quick test, far from ideal conditions, right here on my desk shooting at a book. I noticed that the if I use live-view and Autofocus, it works ok (after 10 shots focus is spot on). But if I shoot at the same spot, without live view I'm back to square one with the camera focusing aprox 1 cm to close. I know that live view uses contrast detection and normal shooting uses phase detection, could my problem be with the phase detection system? It's sensors or something like that?

There is a slight chance of the camera's focusing ground glass is out of adjustment. If you don't look at the little focusing dots and rely on the image you see in the viewfinder, does the sensor's capture (LiveView) match the focus you see on the ground glass?

....send the camera in to Nikon for a focus calibration check.

Keep us informed.

If the focusing ground glass is out of adjustment, how hard is it to fix? I mean, is it routine or mayor surgery? (Assuming that all it needs is an adjustment).
 

pforsell

Senior Member
Ok this is weird... I rarely use live view, actuall I never use live view. I performed a quick test, far from ideal conditions, right here on my desk shooting at a book. I noticed that the if I use live-view and Autofocus, it works ok (after 10 shots focus is spot on). But if I shoot at the same spot, without live view I'm back to square one with the camera focusing aprox 1 cm to close. I know that live view uses contrast detection and normal shooting uses phase detection, could my problem be with the phase detection system? It's sensors or something like that?



If the focusing ground glass is out of adjustment, how hard is it to fix? I mean, is it routine or mayor surgery? (Assuming that all it needs is an adjustment).


What kind of lighting you have when you perform focus tests? It is a well known fact that for example tungsten lighting can sometimes cause phase detect autofocus to misfocus.
 

guillermo_arp

Senior Member
(FRONT-FOCUS is the name of my problem)

What kind of lighting you have when you perform focus tests? It is a well known fact that for example tungsten lighting can sometimes cause phase detect autofocus to misfocus.

That could be a factor. I'll try again tomorrow with daylight. Although I don't believe thats the issue since the problem is always the same: 1cm front focus.
 
Oh no! I'm 1 meter away, or 3.2 feets

I thought I had read 1 foot but actually it was 2 feet.



For this test I shot a book and the camera on a tripod. I was shooting at a specific line aprox 2 feet away, using the widest aperture available.

:confused:

I thought I had read 1 foot but actually it was 2 feet.
Still that is still very close for a very small error. for shooting something this close you really should be using a macro lens. Also from what I have found is that if you set the lens for focusing at normal distances it is going to be slightly off at the very close range. Some of the more expensive lenses may not have that problem but I am not sure of that.
 
Top