Inconsistent Focus Problem on my D7100

Emmanuel

New member
I just bought my new D7100 and I'm having inconsistent focussing problems.
Sometimes, the focus is very "blurry" & noisy. I think that this happens more with aperture < 3.5.
It even happens when I'm shooting with a flash (where I expected to get very sharp photos which isn't the case).
Also, most of the pictures aren't really sharp (I'm most of the time shooting portraits, with AF-S, and when I try to focus one eye, the final result isn't as sharp as I expected).
Can someone help me with this problem ?
I'm using a 85mm 1.8 lens.
 

pedroj

Senior Member
Welcome Emmanuel...Try shooting in AF-C...In AF-S if you or your subject moves after focus has been set the image will be blurry..
 

WayneF

Senior Member
Can you post one? At f/3.5, it could just be a depth of field issue. Is the tip of the nose or an ear any sharper? (in front of, or behind, the eye). Nothing in the background will likely be sharp at f/3.5. Or it could be a slow shutter speed letting camera shake blur it. Or excessive JPG compression could hurt it overall (don't skimp, the best JPG is none too good).

If focusing on the eye, are you selecting single focus point? Is the subject moving? If not, AF-C can only hurt. The default for AF-C is to trip the shutter regardless if it has had time to focus or not. AF-S default will focus first, and then trip the shutter.
 
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Horoscope Fish

Senior Member
I just bought my new D7100 and I'm having inconsistent focussing problems.
Sometimes, the focus is very "blurry" & noisy. I think that this happens more with aperture < 3.5.
It even happens when I'm shooting with a flash (where I expected to get very sharp photos which isn't the case).
Also, most of the pictures aren't really sharp (I'm most of the time shooting portraits, with AF-S, and when I try to focus one eye, the final result isn't as sharp as I expected).
Can someone help me with this problem ?
I'm using a 85mm 1.8 lens.
Are you shooting JPG or RAW?
 

Emmanuel

New member
I'm shooting in RAW.
I'm sure that the subject wasn't moving so I don't think this is the problem.
I'm adding 2 photos (cropped) with the problem. You can see the problem clearly when the photo is at maximum resolution (4000x6000) ; the eyes are blurry and very soft...
The same photo a few seconds before and later was OK, but I want to understand why I can't rely on my camera to have every time a nice, sharp, focused photo.

DSC_0210.jpgDSC_0216.jpg
 
Last edited:

pedroj

Senior Member
If you get sharp images some of the time and not others it is either your technique, movement or slow shutter speed...

Set the scene...Tell us your set up..Aperture...Shutter speed and lighting...Post images with exif data...
 

Emmanuel

New member
The scene : simple portrait with flash (indoor).
Please find the exif information for first photo :

exif:ExifVersion="0221"
exif:ExposureTime="1/60"
exif:ShutterSpeedValue="5906891/1000000"
exif:FNumber="32/10"
exif:ApertureValue="3356144/1000000"
exif:ExposureProgram="3"
exif:SensitivityType="2"
exif:ExposureBiasValue="0/6"
exif:MaxApertureValue="16/10"
exif:MeteringMode="5"
exif:LightSource="0"
exif:FocalLength="850/10"
exif:SensingMethod="2"
exif:FileSource="3"
exif:SceneType="1"
exif:FocalLengthIn35mmFilm="127"
exif:CustomRendered="0"
exif:ExposureMode="0"
exif:WhiteBalance="0"
exif:SceneCaptureType="2"
exif:GainControl="0"
exif:Contrast="0"
exif:Saturation="0"
exif:Sharpness="2"
exif:SubjectDistanceRange="0"
exif:DigitalZoomRatio="1/1"
exif:FocalPlaneXResolution="83841555/32768"
exif:FocalPlaneYResolution="83841555/32768"
exif:FocalPlaneResolutionUnit="3"
exif:DateTimeOriginal="2013-09-09T20:20:17.20"
exif:pixelXDimension="6000"
exif:pixelYDimension="4000"
aux:SerialNumber="4376242"
aux:LensInfo="850/10 850/10 18/10 18/10"
aux:Lens="85.0 mm f/1.8"
aux:LensID="56"
aux:ImageNumber="210"
aux:ApproximateFocusDistance="178/100"
<exif:ISOSpeedRatings>
<rdf:Seq>
<rdf:li>100</rdf:li>
</rdf:Seq>
</exif:ISOSpeedRatings>
<exif:Flash
exif:Fired="True"
exif:Return="3"
exif:Mode="1"
exif:Function="False"
exif:RedEyeMode="False"/>

Please find the exif information for second photo :

exif:ExifVersion="0221"
exif:ExposureTime="1/60"
exif:ShutterSpeedValue="5906891/1000000"
exif:FNumber="28/10"
exif:ApertureValue="2970854/1000000"
exif:ExposureProgram="3"
exif:SensitivityType="2"
exif:ExposureBiasValue="0/6"
exif:MaxApertureValue="16/10"
exif:MeteringMode="5"
exif:LightSource="0"
exif:FocalLength="850/10"
exif:SensingMethod="2"
exif:FileSource="3"
exif:SceneType="1"
exif:FocalLengthIn35mmFilm="127"
exif:CustomRendered="0"
exif:ExposureMode="0"
exif:WhiteBalance="0"
exif:SceneCaptureType="2"
exif:GainControl="0"
exif:Contrast="0"
exif:Saturation="0"
exif:Sharpness="2"
exif:SubjectDistanceRange="0"
exif:DigitalZoomRatio="1/1"
exif:FocalPlaneXResolution="83841555/32768"
exif:FocalPlaneYResolution="83841555/32768"
exif:FocalPlaneResolutionUnit="3"
exif:DateTimeOriginal="2013-09-09T20:25:46.80"
exif:pixelXDimension="6000"
exif:pixelYDimension="4000"
aux:SerialNumber="4376242"
aux:LensInfo="850/10 850/10 18/10 18/10"
aux:Lens="85.0 mm f/1.8"
aux:LensID="56"
aux:ImageNumber="216"
aux:ApproximateFocusDistance="251/100"
<exif:ISOSpeedRatings>
<rdf:Seq>
<rdf:li>100</rdf:li>
</rdf:Seq>
</exif:ISOSpeedRatings>
<exif:Flash
exif:Fired="True"
exif:Return="3"
exif:Mode="1"
exif:Function="False"
exif:RedEyeMode="False"/>
 

Marcel

Happily retired
Staff member
Super Mod
Here is what I would suggest:

Put the camera on a tripod and find a non moving subject. take a few shots using the camera's auto-focus while making sure you manually de-focus it between shots. Then, using live-view, manually focus the shot and take it. Then, if the auto-focus shots are consistently not as sharp as the live-view photos, you might have a real focus problem that only Nikon could solve. But you'd have the images to send them to prove your point.

​Let us know how it turns out.
 

Horoscope Fish

Senior Member
The scene : simple portrait with flash (indoor).
Please find the exif information for first photo :

exif:ExifVersion="0221"
exif:ExposureTime="1/60"
exif:ShutterSpeedValue="5906891/1000000"
exif:FNumber="32/10"
exif:ApertureValue="3356144/1000000"
exif:ExposureProgram="3"
exif:SensitivityType="2"
exif:ExposureBiasValue="0/6"
exif:MaxApertureValue="16/10"
exif:MeteringMode="5"
exif:LightSource="0"
exif:FocalLength="850/10"
exif:SensingMethod="2"
exif:FileSource="3"
exif:SceneType="1"
...
In looking at your shots I'd say there is definitely an issue there. Since you're shooting in RAW you do have to expect to sharpen in post' but those shots are definitely NOT in focus to begin with, not even close. I'm having trouble deciphering what your EXIF data is saying however... In fact I've never seen EXIF data that even resembles what you've posted. How are you extracting your EXIF data?

By way of example here's the EXIF from my D7100:

Filename - PSH_1832.NEF
ImageWidth - 160
ImageLength - 120
BitsPerSample - 8 8 8
Compression - 1 (None)
PhotometricInterpretation - 2
Make - NIKON CORPORATION
Model - NIKON D7100
StripOffset - 127488
Orientation - Top left
SamplesPerPixel - 3
RowsPerStrip - 120
StripByteCount - 57600
XResolution - 300
YResolution - 300
PlanarConfiguration - 1
ResolutionUnit - Inch
Software - Ver.1.01
DateTime - 2013:09:08 00:49:48
Artist -
ReferenceBlackWhite - 0
Copyright -
ExifOffset - 2664
DateTimeOriginal - 2013:09:08 00:49:48
ExposureTime - 1/250 seconds
FNumber - 8.00
ExposureProgram - Aperture priority
ISOSpeedRatings - 100
DateTimeOriginal - 2013:09:08 00:49:48
DateTimeDigitized - 2013:09:08 00:49:48
ExposureBiasValue - 0.00
MaxApertureValue - F 3.73
MeteringMode - Multi-segment
LightSource - Auto
Flash - Flash not fired, compulsory flash mode
FocalLength - 21.00 mm
UserComment -
SubsecTime - 70
SubsecTimeOriginal - 70
SubsecTimeDigitized - 70
SensingMethod - One-chip color area sensor
FileSource - DSC - Digital still camera
SceneType - A directly photographed image
CustomRendered - Normal process
ExposureMode - Auto
White Balance - Auto
DigitalZoomRatio - 1 x
FocalLengthIn35mmFilm - 31 mm
SceneCaptureType - Standard
GainControl - None
Contrast - Normal
Saturation - Normal
Sharpness - Hard
SubjectDistanceRange - Unknown

GPS information: -
GPSVersionID - 2.3.0.0

Maker Note (Vendor): -​
 

Emmanuel

New member
I have extracted the exif information from the xmp file of Lightroom.
I made some more tests, and I can clearly see that I'm having those problem with aperture < 3.2
If my aperture is 4.5 for example, I got clear sharp photos.
When aperture is 2.8, I got most of the time blurry, noisy photos.
Does anymore shooting portraits with 85mm f2.8 have the same problems ?
I would appreciate if someone can post a portrait photo made with 85mm 2.8.

I'm attaching 2 more photos : the first with 85mm 5.6 and the second with 85mm 2.8.
You can clearly see the difference in sharpness.
I'm just wondering if the problem happens only with my camera, or if it's a general problem with d7100.

_DSC0801.jpg_DSC0825.jpg
 

Emmanuel

New member
Hi Alan,
I like portraits being shoot at 2.8. It usually gives me great background and nice sharp portraits (the focus is all the time in the eyes and therefore I don't really care if other part of the face is less focussed).
Anyway, I expect my NIKON camera to give me focussed photos even when I shoot at 2.8.
With my previous NIKON camera, I never had any problem (and I'm shooting already more than 10 years with NIKON).
 

Emmanuel

New member
I made some new tests with my D7100 in order to test my inconsistent autofocus problem and I came to interesting conclusions.
I took photos of three books, the most right book, is the closest to the camera, then 2 cm more far, and the last one (left book) is again 2 cm behind.
I have focus on the middle book (which means that the left one is 2 cm behind, and the right one is 2 cm in front).
I'm attaching two photos I took at f1.8 (I made a lot of tests, and all came with the same conclusion).
We can clearly see that sometimes, the focus is +/- OK (focus in the middle book), but when I took the same photo a few seconds later (or earlier), the focus is much more closer to the right book (although the focus point is still always in the middle book).

My camera has clearly an unstable autofocus problem. Sometimes is +/- OK, sometimes, it's much more focus on the right book (front).

Does anyone have the same problem ?
I'm wondering if this is a general problem with the D7100, or if it's a problem only with mine ?
Anyway, I returned my camera to Nikon's lab for further investigation (waiting for their conclusions).
Screen Shot 2013-09-18 at 10.56.01 AM.jpgScreen Shot 2013-09-18 at 10.56.22 AM.jpg
 

John P

Senior Member
I think you are asking quite a bit for those Fstop settings.
At F1.8 depending on your distance. You may only get one eye in focus.
 

Emmanuel

New member
Hi John,

Like I mentioned, the problem is not the small depth of field, but the consistency with the focus.
Even at 1.8 or 2.8, you should get consistent focus (even with small depth of field).
I received an official answer from Nikon yesterday where saw a focus problem with my camera and it is now for further investigation in their lab. Let's hope that they will be able to tell me the exact problem I'm having with my camera.
Anyway, thanks for your feedback,
 

Horoscope Fish

Senior Member
I think you are asking quite a bit for those Fstop settings.
At F1.8 depending on your distance. You may only get one eye in focus.
If this were a DOF issue I would think we would be seeing *consistent* softness; the focus POINT of the shot should be sharp at f/1.8 even if something half an inch away is not. The photos of the books in post #15 were taken seconds apart at the same aperture, same distance from the (flat) subject and yet the focus point of one shot is definitely softer than the other. I don't even need to enlarge them, I can spot the difference between the two just by looking at the thumbnails.

.....
 

gohan2091

Senior Member
@Horoscope Fish how did you get on with this? I THINK I am experiencing the same issue. On a tripod using a remote control to operate the shutter, focusing on the same point over and over isn't always resulting in correct focus. It appears random, sometimes it would be sharp and others less sharp yet the focus point hasn't changed! This is with my Sigma 105mm @ <F3.5
 

Horoscope Fish

Senior Member
@Horoscope Fish how did you get on with this? I THINK I am experiencing the same issue. On a tripod using a remote control to operate the shutter, focusing on the same point over and over isn't always resulting in correct focus. It appears random, sometimes it would be sharp and others less sharp yet the focus point hasn't changed! This is with my Sigma 105mm @ <F3.5
I'm not sure I'm understanding what you are asking... I was trying to help someone who seemed to be having a focus issue, I'm not having any focus issues personally.

Your issue, though, *could* be one of technique. Just a guess but I wonder if the camera isn't trying to re-acquire focus when you press the remote release. I don't have my remote here with me at the moment so I can't test that theory myself... However, when using a remote shutter release, I like to achieve focus, then lock focus using the switch on the back of the camera, then I take the shot. This is just something I do out of habit but now I'm wondering if this is reason I do that. Of course sometimes it's easier to put the *lens* into "M"anual focus mode, instead of using the switch on the camera, but you get the idea. Make sure your camera isn't trying to re-acquire focus when you press the remote. It might be, and in so doing, focusing at times on something other than what you intended.

If this ISN'T the problem then we'll look elsewhere. I hope something in there that helps...

...
 
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