# D800 + wide angle trouble nailing focus



## Heitz (Jun 17, 2012)

Hey all, I got my hands on a D800 recently, and upgraded lots of glass.  For my wide angle needs I got the Nikon 20-35 2.8D.  Now, for the most part I'm able to nail focus with every other lens but this one, and I'm wondering whether this is a real problem or whether I'm just so used to pixel peeping with telephoto that my standards are too high.  Here is a pic of a deer that was totally motionless.  I managed to get a bunch of clicks on him to make sure that my AF-C had all the chance it could to focus properly.  This was the best of the bunch, 1/200 @ 35mm, ISO 400, and f/3.5.  

Can someone please verify that this is actually softer than it should be?  And if so, anyone have any idea what's going on?  Either the D800 has trouble focusing at wide angle or the 20-35 is intolerably soft.

Thanks in advance.


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## 480sparky (Jun 17, 2012)

It would be nice to be able to download an original file to see where the focus point was.  Or are you focusing manually?


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## Robin Usagani (Jun 17, 2012)

you have to use only 1 focus point.  Too much stuff in front of the deer to miss focus.


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## Heitz (Jun 17, 2012)

Used only 1.  Here it is straight from ViewNX, along with focus point and 100% crop.  Does this look out of focus?


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## Robin Usagani (Jun 17, 2012)

Yes.. but that looks like a huge focus point.


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## mjhoward (Jun 17, 2012)

Is there anything in the photo that looks sharp?  That might offer insight as to whether you missed focus or the lens doesn't have enough resolving power.  It would seem at that distance the DOF would be rather large so if you were even close to hitting the correct focus, you would think your subject should still be acceptably sharp.


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## DiskoJoe (Jun 17, 2012)

Have you tried a smaller fstop? Like f8? 3.5 is pretty shallow for a scene like this.


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## Robin Usagani (Jun 17, 2012)

DiskoJoe said:


> Have you tried a smaller fstop? Like f8? 3.5 is pretty shallow for a scene like this.



Dude... 3.5 wide angle with focus distance that far has plenty of DOF.


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## 480sparky (Jun 17, 2012)

Schwettylens said:


> DiskoJoe said:
> 
> 
> > Have you tried a smaller fstop? Like f8? 3.5 is pretty shallow for a scene like this.
> ...



Assuming the focus point is really where the lens focuses.  Looks like the background is sharp.

I wonder if this is a back-focus type issue.


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## Robin Usagani (Jun 17, 2012)

This doesnt happen to a Canon..  I swear!


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## 480sparky (Jun 17, 2012)

Schwettylens said:


> This doesnt happen to a Canon..  I swear!



How would one know?   Is there software for Canon images that can show which focus point(s) the camera used?


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## Robin Usagani (Jun 17, 2012)

480sparky said:


> Schwettylens said:
> 
> 
> > This doesnt happen to a Canon..  I swear!
> ...



Yes, the software that comes with the camera does...  And this is supposed to be a joke .l


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## Joshonator (Jun 17, 2012)

It could have been that the focus point was on the tree when you autofocused and then before you took the shot you moved down a bit.


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## cgipson1 (Jun 17, 2012)

We need exif data...  Were you actually *spot focus (single point AF) mode and AF-S*? .. or were you in one of the other focus modes?  If you were in AF-S.. the focus point only shows in Single Point Mode....Auto doesn't show it. If you were in AF-C.. the focus point shows in Single Point, D9, D21, D51 and 3D.. but not in Auto. 

It would also help to see a full size image...


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## Ernicus (Jun 17, 2012)

I didn't know capture would show your focus point like that.  Man...after reviewing some images...I miss focus a ton.  Thanks for this thread.


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## Ernicus (Jun 17, 2012)

quick question...if I have say a dragon fly in view...focus point on eye...half press and get the beep, then move to re frame...will capture still show focus point as the eye or where ever the dot that it used for the focal point end up in the frame?


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## Ernicus (Jun 17, 2012)

I just answered my own question.  Turns out that is not a very helpful tool at all.  In the image below I focused on the "enter" key, half shutter press, got beep, moved center point to cigarette pack.  Focus stayed on the "enter" key as I wanted it to, but the focus point shows the smoke pack as focus point.

So in relation to this thread, the focus point on the deer means nothing if you moved to reframe shot in any slightest direction.


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## cgipson1 (Jun 17, 2012)

When you re-frame.. you are moving the focus point! That is why focus and re-compose gets so many people in trouble!


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## Ernicus (Jun 17, 2012)

cgipson1 said:


> When you re-frame.. you are moving the focus point! That is why focus and re-compose gets so many people in trouble!


  Well sure you are technically moving the "focus point" as the dot you used as your point indicator moves...but you have also locked in focus on a different point of the image...so that should be reflected as your true focal point, as in the area of the image that was the focus point.

Or am I playing on words here?


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## cgipson1 (Jun 17, 2012)

Ernicus said:


> cgipson1 said:
> 
> 
> > When you re-frame.. you are moving the focus point! That is why focus and re-compose gets so many people in trouble!
> ...



The area of focus is where the focus point is *in the viewfinder* when you lock focus. And it stays at the point in the viewfinder, even if you then point the camera straight up in the air and actuate! The camera doesn't know any better (YOU locked the focus) and it can't pass that change to software! Does that help?


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## Heitz (Jun 18, 2012)

cgipson1 said:


> We need exif data...  Were you actually *spot focus (single point AF) mode and AF-S*? .. or were you in one of the other focus modes?  If you were in AF-S.. the focus point only shows in Single Point Mode....Auto doesn't show it. If you were in AF-C.. the focus point shows in Single Point, D9, D21, D51 and 3D.. but not in Auto.
> 
> It would also help to see a full size image...



Good catch cgipson1.  It was not AF-S, it was AF-C with 9 focus points, not 1.  Which means that it is possible I could have focused on the tree above the deer, then moved down some and the camera wouldn't have refocused if the tree was still within the 9-point region.  I'm continuing to do tests with single-point AF-C or AF-S (never auto).


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## cgipson1 (Jun 18, 2012)

Heitz said:


> cgipson1 said:
> 
> 
> > We need exif data...  Were you actually *spot focus (single point AF) mode and AF-S*? .. or were you in one of the other focus modes?  If you were in AF-S.. the focus point only shows in Single Point Mode....Auto doesn't show it. If you were in AF-C.. the focus point shows in Single Point, D9, D21, D51 and 3D.. but not in Auto.
> ...



damn.. I actually got something right for a change! lol!  Glad I could help!


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## BXPhoto (Jun 18, 2012)

Well to be honest, 1/200th even at the FL can create minor hand shake. Also the lens could simply be back focusing. Or he recomposed and didnt realize it. Too many variables to be used as a test shot. Also look at all the artifacts in front of the focus point and before it. Even my 7D/5d2 in spot focus/center point could have had an issue due to user error. Take a shot in bright light in an open area of a contrasty subject on a tripod. This way it will remove a few variables (steady hands, accidental recomposure etc).


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## spacefuzz (Jun 18, 2012)

Also dont be afraid to jack up the ISO on the D800, I have gotten really nice shots even as high as 3200.


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## Heitz (Jun 21, 2012)

Update -- The Nikon 20-35 2.8D had a huge back focus on my D800.  Corrected with AF Fine-tune -15.  

Curious -- anyone know what causes back focus for a particular lens?  Don't quite understand why that would happen.


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## BlueMeanieTSi (Jun 21, 2012)

Yeah the branches behind the tree that is behind the deer are pretty dang sharp.


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