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monsters
21-05-2011, 8:05pm
Hi everyone,

Recently I have bought a nikon 35mm f1.8G lens and I realise that a few of my photo is out of focus. My lens was focus on the subject's face but when the picture came out the subject's face is out-of-focus and you can see that the background is clear.

Is my lens having a focusing issue or there's something wrong my technique/setting or camera.

I am still new to photography. I hope to get some advices from you all

Thanks for your input.

p.s. i will try to post a few photo up as example. By the way, 1st photo , was taken at f2.2, iso250, shutter speed 1/250.
And second wedding image is taken at f2.8, iso200 and at 1/125.
7264972650

dbax
21-05-2011, 8:26pm
mmm I don't use or know very much about Nikon at all but, the EXIF data on these images show metering mode unknown and focus distance as 0 m. I'm wondering if the camera and lens aren't talking to each other ?
A Nikon user will be along and offer better info before long

EXIF from image #1

Camera Maker: NIKON
Camera Model: *
Image Date: 2009-05-20 00:12:10 (no TZ)
Focal Length: 35.0mm
Focus Distance: 0m
Aperture: f/2.2
Exposure Time: 0.0040 s (1/250)
ISO equiv: 250
Exposure Bias: none
Metering Mode: Unknown
Flash Fired: No
Orientation: Normal
GPS Coordinate: undefined, undefined

monsters
21-05-2011, 8:40pm
Thanks Dave.
Appreciate your help. Will all these info usually comes with the photo?
How can i find out?
I am currently using faststone to view my photos.
Cheers

dbax
21-05-2011, 8:50pm
yep most photos show EXIF data unless its removed by the up loader. To view the data you need to download and install an EXIF reader. There are many available just google exif reader. I use Opanda http://www.opanda.com/en/iexif/

monsters
21-05-2011, 8:58pm
Cheers mate.
I am keen to find out what's wrong with my lens and/or camera or my technique.
I really love this lens but only recently i find that the lens focusing is not very consistence.
Hopefully more dslr guru can share their experience and advice.

arthurking83
21-05-2011, 10:15pm
As dbax said. the vital exif data(that we need to understand how the camera was set up) is missing.

You seemed to have used dcraw to convert the raw file to jpg(maybe).

You shoudl have a copy of ViewNX on the CD that came with the camera.

If you use VNX to convert and resize the images for web upload, it will retain all of the required exif data we need to view.

To work out what's wrong or what went wrong, we also need to understand your technique too.
ie. did you focus and recompose, did you focus hesitate for a second and then expose... etc.
Where exactly in the images was the point of focus?
The focus point should be in the exif data, and some software can display this info in the embedded jpg preview image.
ViewNX will also allow you to view the exact point of focus as well(there's a small tool in the toolbar to turn this on/off as you please).

If you could repost at least one of the images with the entire exif data complete, we can start to explain (if) there is a settings problem, or whether you have a camera/lens issue.

BTW: the stripping of various pieces of exif data is a common issue with many image browsers/converters when you save new copies of the file.
The only two free programs that I know of(ie. and use) that will not do this, is ViewNX(1 or 2) and FSViewer.

monsters
21-05-2011, 10:29pm
On to it now...
getting the software installed now. Brb. Thanks for helping :)

monsters
21-05-2011, 10:59pm
Alright, thanks guy for the advice and help.
I have quickly installed the software that came with my camera.
Here are the updated and one new photo.
Thanks guys!

1.
72659
2.
72660
3.
72661

swifty
21-05-2011, 11:32pm
A couple of questions:
What focusing mode were you in: AFS, AFC or M
Did you focus, half press and recompose? Just focus using central AF or changed your AF sensor to the appropriate point then press the shutter?
Did you get a focus comfirmation (solid green dot in viewfinder) before actuating the shutter?

There's a lot of variables when it comes to getting accurate focus.
Often its user error, sometimes the camera sensors fumbles and focuses on an adjacent area with slightly more contrast.

The thing is, it appears the focus is way off in each case suggesting the camera/user got a lock on the wrong subject before actuating the shutter rather than backfront focus which is usually more subtle.
Also note that the AF sensor sometimes is slightly off compare to the indicated AF points in the viewfinder. The size of the AF sensors is usually different to the indicated AF point too (God know why?) so these nuances can sometimes trip up the end user until you get a good handle of how the camera operates.

arthurking83
21-05-2011, 11:55pm
thanks for that.

first off I edited your post to make the explanations more simple

in the first image the point of focus is on the girls collar on the red spot.
if your technique was that you focused on her face and then composed to that particular framing, then (with 99.9% surety) as you recomposed, you have moved yourself in relation to where the plane of focus was at the time of focus, and from the resulting image it seems to be forward. That is in the time between focusing and then turning/moving yourself to get a composition you like, you most likely leaned forward...ie. focus lost
You used AF-S(single shot focus mode) where the camera focuses only once and shoudl give a confirmation beep when it does. If you delay the time to actual exposure you also risk getting subject movement too.. similar to you leaning forward.
The main data required from the exif was whether you'd used AF-A mode, where the camera chooses the point of focus.

tips for better focusing accuracy with this method. Get used to using the joystick pad on the back of the camera to select an appropriate focus point. Set the camera to AF-C. half press the release to maintain focus accuracy and then shoot.
Alternatively, you could also set the AE-L button near your right thumb to act as a focusing button, where you maintian focus as you shoot a few continuous frames. There's nothing wrong with shooting 3 frames to get one excellent copy. you can easily delete the other two frames if they're no good to you.

image #2. a plausible explanation of why the focus is not on the girl, but instead on the man behind her. Unfortunately there is no focus point data in that image. This happens when you use AF-C mode, because the camera simply can't maintain a fast enough focusing routine, so what it does is to simply focus when it feel it needs too. Did you shoot a few frames of this one? This is common, and one reason you spend the extra money on a D300 over a D90(or even a D7000).. and better still spend even more on a D3 series of some sort. The camera's ability to focus quickly has an impact here.
But as I said also, as there is no focus point data we can only assume that the central focus point is used. In this particular shot that point coincides with a point where the girls face is AND where the man's neck is.
What does this mean in real life? focus hunting. The camera's focus points are not points at all, but a series of lines, in that focus square. it sees two possible areas to focus on, so it chose one, which is not the one you wanted to to use.
A good technique would be to make sure that only the girls face is within the bounds of the focus square, even if that means losing a small amount of compositional excellence. You can always crop 2% of the image later on to suit anyhow.
otherwise as before choose a focus point that is more suitable.

in image #3, it's obvious that the focus is on the two people hugging and not on the smiling man. The focus point is on the smiling man's (second from the top) button.
Why there's such a disparity in the where focus is (assumed) and where it actually ended up to be, is hard to fully understand.
If you didn't focus and recompose in this one, you could only come to the conclusion that the lens may have been hunting a bit for no good reason.
That is, at the point of focus, there is very good contrast for the focus system to lock onto. The focus square is well within a good range of contrast to focus on, so there is no good reason for the focus system to not lock onto the man's second button, or at a point where the white shirt meets the black jacket.

from these images, I'd be loathe to say you have either a camera or lens issue.

Do a few more tests before you condemn either to the service centre.

understand how AF works, and what is required to assure yourself of a good focus target to get a higher hit rate.

The way AF works is by 'seeing' a high level of between pixels.
That is, imagine a sharply defined line between a white square with a black square and point the AF square at the point, and you always get 100% focus accuracy along that plane. The camera is set to determine the best possible contrast between the black and white line to create a visibly sharp line.
A white or black or any coloured solid surface provides no contrast for the AF system to lock onto.

if you are having trouble getting the camera or lens to focus accurately there are a few simple tests you can do to work out for yourself if this is an issue.

ATM, I'd be working on technique and in doing so learning more about what works and what doesn't when it comes to focusing.

Hope that helps a little.

monsters
22-05-2011, 3:03am
Hey Swifty and Arthur,
Thanks guy for the explanation. Thanks Arthur for the amount of time you put in to explain what may have gone wrong and how I can try out a few things to further determine what went wrong.

I think I will need to read the comments again tomorrow and also try out a few things you guys have mention along side. I find your inputs are very helpful and hopefully i can solve the issue. I hope both the d90 and lens are working 100% and that it's my technique.
Surely i will report back and find out what went wrong.
By the way, I am situated in Perth, south of the river. Worst come to worst I may need a real time tutorial :)
Good night and have a wonderful Sunday!

Kind regards
Sim

arthurking83
22-05-2011, 10:49am
No worries Sim.

Just in case too. If you find that the camera lens combo isn't focusing accurately, unless you have a tripod to work with(can be any tripod, not necessarily an uber expensive pro model), you will be hard pressed to determine for sure if there really is an issue.
That is, there's no point taking the gear back to the shop and saying "this lens is back/front focusing" when they end up testing it properly and finding nothing wrong with it. Doing that only wastes your time.

ps. God was mistakenly quoted with respect to the purpose of Sunday!!
He supposedly said Sunday is the day of Rest, when he really said Sunday is the day of Test.
You know.. testing gear, test cricket... etc, etc
Rest.. test ... hey after 6 days of hard work, and the only thing on your mind is a day of rest, I can easily see how these two words can easily be confused :D

I @ M
22-05-2011, 3:27pm
Image 1 and 3 are showing in View NX2 as having been taken with dynamic focus area selected.
That would indicate to me that the camera is selecting where to focus instead of the operator.

arthurking83
22-05-2011, 3:59pm
Image 1 and 3 are showing in View NX2 as having been taken with dynamic focus area selected.
.....

Aha! Is that what the value 0x1 means!

Using PhotoMe, I'm only seeing the Focus Area mode as this value of 0x1.
I'm guessing that VNX v1 may be distorting the exif data slightly, when viewed with third party software, but still maintains coherence when using Nikon software(to be expected).

Haven't used VNX1 in years tho, but VNX2 doesn't appear to play silly buggers with the exif(as subsequently read with third party software at least).

Sim, do yourself a favour and uninstall ViewNX v1(seems like you're using v1.1, you can see this info if you click Help->About).
Download ViewNX2 .. from HERE (http://nikonasia-en.custhelp.com/app/answers/detail/a_id/162#ViewNX2).
It's not perfect, but for the money it's good enough despite it's shortcomings.
I doubt you will find a better NEF converter for free.

monsters
22-05-2011, 7:15pm
Thanks Arthur and I@M,
I am downloading the View nX2 now from the link provided and installing it too.
Thanks for the replies and advice. I am finding myself learning new things here and am enjoying it.
I took a few more picture today, will post it up soon :D

monsters
22-05-2011, 7:26pm
Thanks Andrew for the info. Is dynamic focusing a good thing or not?

I @ M
22-05-2011, 7:50pm
Thanks Andrew for the info. Is dynamic focusing a good thing or not?

Yes and no ---

If you are trying to catch rapidly moving subjects in unpredictable directions then it may be the solution but in the case of your shots on here it is most certainly not the way to go.
Autofocus and the myriad of variables available to you with your camera are quite a learning curve on their own but generally speaking in a situation like the wedding you have photographed you most assuredly should be working in a single autofocus point that you dictate to the camera.
Locking exposure, focus point, (separately) recomposing and shooting are an area that needs lots of study.

monsters
22-05-2011, 8:03pm
727327273372734

monsters
22-05-2011, 9:02pm
just took a few more before the light disappear...7275172752

kiwi
22-05-2011, 9:07pm
the snags look nicely in focus, id say youre onto something. Id use single point focus for awhile to get the hang of it

monsters
25-05-2011, 10:27pm
Thanks guys. No time lately to test out the lens and the sun is setting earlier now. By the time i got home from work, it's almost dark!
Anyhow, thanks for all your advices. I also realised that the lens seems to focus well on a close-up shoot/photo compare to like group photo or from a distance.

dannyz
29-09-2011, 1:39pm
I found the same thing initially when using auto AF-A settings on full Auto.. Now i control my own focus points.. best thing i did was use the directional keypad to choose my own focus points.. I tend to use 'AF-C' more as im usually focusing on something moving like little-uns. I have found that the 35mm 1.8 hunts a little more then my 18-105 though..

A J Alderson
29-09-2011, 2:29pm
I had the same problem with my d90 and 35 1.8g. I found a post on the web on how to manually adjust the focus. I cant find it now but all I had to do was remove the lens, tape the mirror in the raised position than adjust the bottom hex screw inside the (right side facing you) body. I was back focusing so a half turn down and some fine tuning with a focus test chart brought it back to spot on. I assume the body was the issue because my new macro lens focuses perfectly too. I was mainly using wide angle lenses before so I never noticed the problem until using shallow DOF with the 35mm.

Hope this helps

bgolds99
29-09-2011, 6:49pm
Don't go adjusting your body's focusing system just yet. AJ, you might have had a back/front focus issue, but it doesn't look like that is the case with Monster's lens. I have this combo (35/1.8G & D90) and have had no problems whatsoever with the focusing of the lens. It's actually one of the faster focusing lenses i have, and insanely sharp when focused properly. I think it just takes time getting used to the DOF of these lenses, realising that having the slightest offset of the focus point can completely make or break the image, unless you're cranking the aperture up above 8 or so. WIthout zooming in at all, the photo of the snags and the flowers look decently sharp to me.

Cheers, Brad.

monsters
01-10-2011, 12:43pm
I had the same problem with my d90 and 35 1.8g. I found a post on the web on how to manually adjust the focus. I cant find it now but all I had to do was remove the lens, tape the mirror in the raised position than adjust the bottom hex screw inside the (right side facing you) body. I was back focusing so a half turn down and some fine tuning with a focus test chart brought it back to spot on. I assume the body was the issue because my new macro lens focuses perfectly too. I was mainly using wide angle lenses before so I never noticed the problem until using shallow DOF with the 35mm.

Hope this helps

Thanks for the info. I dont think I am brave enough to do the adjustment unless I have specific instructions. Also, mine is still under warranty. I am slowly getting use to it now, by focusing at different point to get my photo sharp and clear.
But if you could provide the web link I may have a read on it. Very good info. Thanks!

monsters
01-10-2011, 12:46pm
Don't go adjusting your body's focusing system just yet. AJ, you might have had a back/front focus issue, but it doesn't look like that is the case with Monster's lens. I have this combo (35/1.8G & D90) and have had no problems whatsoever with the focusing of the lens. It's actually one of the faster focusing lenses i have, and insanely sharp when focused properly. I think it just takes time getting used to the DOF of these lenses, realising that having the slightest offset of the focus point can completely make or break the image, unless you're cranking the aperture up above 8 or so. WIthout zooming in at all, the photo of the snags and the flowers look decently sharp to me.

Cheers, Brad.

Cheers Brad,
Thanks for your feedback. I guess I am still learning to use my lens properly and hopefully over time, I can compose and take good photos. I love this lens so much so that if i have spare $$$ i may get the f1.4 version!!! hahaha... but I dont!!
Thanks again guys for helping me up. Definitely need the advise and help in my photography :)

monsters
04-10-2011, 2:07am
Just one photo - I think it's focusing quite well now :D

monsters
01-11-2012, 6:37pm
Hi, i just realised that I did not close/conclude this thread properly.
Sorry about that. September last year, I took the lens to a authorised Nikon repair store for a check-up and the result came back with back-focusing issue.
As the lens was under warranty, I got it adjusted/fixed for free of charge. So now the lens is focusing properly and performing flawlessly.
Thanks for all the advise, concerns and comments.

rgds,
Monster

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