# Tips for improving focus.  ??



## AMOMENT (Apr 21, 2012)

I have a Nikon D3100 and often use either my 50mm 1.4 lens or my 55-300 f/4.8-5.6  My camera has 11 AF points but I have noticed that unless I use the central one (which has crosspoints) my focus is always blurry.  Even if I raise my aperture to increase depth of field and my distance from the subject.  (in some cases)  For this reason I often shoot af-s , lock focus, and then recompose.  I recently posted some pics in the People gallery and people said what I suspected, which is that my focus was off.  I don't necessarly understand why.  I am not shooting wide open, at least for now, to comopensate for my tendency to miss focus.  I almost never shoot with a shutter speed slower than 1/200.  

When I shoot moving children I still usually shoot af-s and just hope for a still moment and snap quickly.  When I shoot af-c, I almost never get the shot because by the time my camera locks focus, the moment is over.  I am shooting single point but I wonder if I should be shooting dynamic for moving kids.  I suspect no because I generally want the child to be highlighted.  


What else can I do to improve my focus?  Since I am shooting with AF and obviousely not MF, it seems to me that these are all the adjustments I can make. I could use a tripod but this would be nearly impossible to do and use when shooting kids who are all over, constantly changing their positions and whereabouts.  I'd be running around with a tripod and there would be no time for even adjusting to get down low or move up higher.  

-I'm not shooting wide open

-I'm putting more distance between my subject and I when needed (but not too much so that the camera does not focus)

-I am not shooting at a shutter speed slower than 1/200 and MAYBE slightly below that.  Most of the time it is faster.


If you need some examples I posted two shoots in the People Gallery.   Thank you all


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## jake337 (Apr 21, 2012)

AMOMENT said:


> I have a Nikon D3100 and often use either my 50mm 1.4 lens or my 55-300 f/4.8-5.6  My camera has 11 AF points but I have noticed that unless I use the central one (which has crosspoints) my focus is always blurry.  Even if I raise my aperture to increase depth of field and my distance from the subject.  (in some cases)  For this reaso_*n I often shoot af-s , lock focus, and then recompose.*_  I recently posted some pics in the People gallery and people said what I suspected, which is that my focus was off.  I don't necessarly understand why.  I am not shooting wide open, at least for now, to comopensate for my tendency to miss focus.  I almost never shoot with a shutter speed slower than 1/200.
> 
> When I shoot moving children I still usually shoot af-s and just hope for a still moment and snap quickly.  When I shoot af-c, I almost never get the shot because by the time my camera locks focus, the moment is over.  I am shooting single point but I wonder if I should be shooting dynamic for moving kids.  I suspect no because I generally want the child to be highlighted.
> 
> ...



When you focus and recompose you are shifting the focus plane no matter what aperture you use.

So you are saying when you choose any other focus point besides the center it does not focus properly?  Have you tested this on a tripod on static subjects?


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## Dao (Apr 21, 2012)

Just one quick question, do you shoot raw and sharpen the photo during post?


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## tirediron (Apr 21, 2012)

Avoid focus and recompose.  Depeding on the angle, and especially if you are close to the subjects, it can drastically alter your focus on the subjects.  First, as mentioned, verify by use of static subjects and a tripod that your camera is focusing corretly (I'm 99.99999% sure that it is), and, assuming that to be the case, then get your kids, take 'em outside, Feed each of them ten large Slurpees, and let 'em go, and spend an hour practicing.   Get used to selecting a particular focusing point, and nailing the focus.  I use AF-S for all types of work from portraits to children, to motorsports.  Did I mention?  Practice!


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## AMOMENT (Apr 21, 2012)

(Jake337) no I haven;t but I will do a focus test today and post.....

I would love not to have to recompose but it seems that whenever I use any other AF point other than the middle, despite my steps to increase DOF, it becomes blurry.

(Dao)  I do shoot raw and sharpen but try not to overdue it.  

(tirediron) THANKS!  I feel like I practice like crazy and still drasntically miss focus.  I do have a shaky hand for whatever reason.  I've tried holding my breath or stabalizing the camera through different positions.  I will do a focus test and post pics later...


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## MTVision (Apr 21, 2012)

AMOMENT said:
			
		

> no I haven;t but I will do a focus test today and post.....
> 
> I would love not to have to recompose but it seems that whenever I use any other AF point other than the middle, despite my steps to increase DOF, it becomes blurry.



I would try a focus test with all your focus points as well. I rarely use the center point and I haven't had any issues. All focus points should be useable.


EDIT: in your other thread titled something child photography there is a picture of your daughter #4 in the post. It looks to be decently focused but your depth of field was pretty shallow and if you recomposed you could've really lost focus. 

The zoom lens you have is going to give you a shallower DOF at f5.6 (depending on your distance) then the 50mm.  From your exif of that photo it says you shot with a focal length of 125 and an aperture of f/5.6. For the distance to subject the exif says 67/20m which I think is like 11ft (if I'm reading it right). 

With that focal length, aperture and distance you had .42 ft of depth of field (5 inches). Which is not a lot at all. With longer focal lengths to increase depth of field so you get better focus you are going to have to put more distance between you and the subject and/or use a smaller aperture.


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## Derrel (Apr 21, 2012)

I would switch to using AF-C focusing for kids in motion. I think AF-C simply works better and is the "appropriate" mode for action shooting...it keeps the camera focusing all the time. You say you are "hoping for a still moment"...and yet, your focus is very frequently "off"....well...you need to shift the focusing switch to AF-C, so that the camera is CONSTANTLY able to re-focus, as the subject moves.


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## SCraig (Apr 21, 2012)

Derrel said:


> I would switch to using AF-C focusing for kids in motion. I think AF-C simply works better and is the "appropriate" mode for action shooting...it keeps the camera focusing all the time. You say you are "hoping for a still moment"...and yet, your focus is very frequently "off"....well...you need to shift the focusing switch to AF-C, so that the camera is CONSTANTLY able to re-focus, as the subject moves.


What he said.  If you can't get a focus lock on a moving kid something is wrong unless they are coming straight at you.  I've gotten focus lock on motorcycles traveling close to 200mph on a race track, birds in flight, jet fighters in flight, drag cars at launch, all with no problems.

I seldom use anything but AF-C except for landscapes and I seldom use anything other than the center focus point (in 4 years of using cameras with the ability to change the focus point I can remember doing so once).  I never, ever use 3D dynamic auto tracking or whatever it's called, the focus points dancing around all over the place drive me nuts.

If your subject is moving my guess is that you are inducing motion blur or not panning with the subject.  If you aren't panning (properly!) with a moving subject you should be shooting much, much faster than 1/200 second.


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## AMOMENT (Apr 21, 2012)

Thanks everyone!  Here is my focus test.  Grantid the exposures and everything is off but I just wanted to show you my focus.  There are 4 images.  I used my 50mm 1.8 lens and set up 10 feet away.  My aperture was 7.1 and shutter 1/800 (I believe) The first one is with my center point, the second with the bottom, third with the top, and fourth with the upper left.  (I didn't do all 11) Important to note that I originally did the focus test on a children's basketball hoop (about 4 feet from ground) and EVEN when stationed on a tripod, AF-S and using center point, my camera would not lock focus and allow me to take the photo when that center point was targeted at the whie backdrop of the hoop.  My suspicions have always been that my camera latches onto a FP that has the mose contrast.  (which would make sense) but I was still surprised.  For instance, if I take a photo of a child with a bright headband on, even when AF is locked on their eye, the headbad will be sharper.  


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## AMOMENT (Apr 21, 2012)

Thank you, Megan.  I do believe you are right in that my DOF was too shallow.  I think I really need to practice adjusting my DOF spontaneousely and being able to do so without recalculating on my DOF calculator.  I often get an estimate of DOF I'm lookinf for before hand so I have a general idea where I want to position myself in relation to my subject.

I have the Adobe DNG converter and for the last two days it has not successfully converted anything.  I had a folder with only 4 images that I was trying to convert and when it popped up it said there was like 146 in there. I have only one folder selected and have it set to save in the same folder.  All settings are the same.  I restarted my computer, ran spybot, and still same problem.  Also, after  attempt to convert and it says it was converted successfully (though it hasn't been) the whole rogram pops up again without me prompting.  Have you run into any problems with this program?  I know you have used it.....


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## AMOMENT (Apr 21, 2012)

Derrel said:


> I would switch to using AF-C focusing for kids in motion. I think AF-C simply works better and is the "appropriate" mode for action shooting...it keeps the camera focusing all the time. You say you are "hoping for a still moment"...and yet, your focus is very frequently "off"....well...you need to shift the focusing switch to AF-C, so that the camera is CONSTANTLY able to re-focus, as the subject moves.



If I depress shutter halfway on my moving subject and then pan and try to shoot, it doesn't allow me to take the picture (on AF-C)  ...it begins re-zooming/adjusting/focusing to the point where it is almost pointless and impossible to get much of anything "in the moment."  Any suggestions?  I'm sure I am doing something wrong but I don't know what..


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## AMOMENT (Apr 21, 2012)

These next two photos are WRONG in every way but I simply used them and took them to test my other AF-points.  These two were taken using the upper left point which I positioned on her right eye (if we were looking at her, left) and even though I was still and my subject was, and my DOF was sufficient, you can see how blurry it is.  I then took a picture using the center point after this and got a much more in focus shot.

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## Josh66 (Apr 21, 2012)

tirediron said:


> Avoid focus and recompose.


:thumbup:

Why Focus-Recompose Sucks


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## SCraig (Apr 21, 2012)

AMOMENT said:


> ... The first one is with my center point, the second with the bottom, third with the top, and fourth with the upper left.


It's doing what you are telling it to do.  The first one is focused on the flower, the second on the rail of the fence under the chair, the third I can't really tell because it's in the trees somewhere, and the last one, upper left focus point, is focused on the house in the background.


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## MTVision (Apr 21, 2012)

I think doing a focus test like the one in the link below will be a lot more accurate. It will help determine if your lens is back focusing/front focusing or if it's focusing properly. 

This link brings you to the chart that you print out - or you could use a ruler
http://www.photo.net/learn/focustest/scale45.jpg


These are the directions

http://photo.net/learn/focustest/

I think this test will probably be a lot more accurate.


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## AMOMENT (Apr 22, 2012)

Megan, a while ago MLEEK looked at some of my photos and suspected front focusing.  What would I do to fix this?  I'd prob have to send it in right?


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## MTVision (Apr 22, 2012)

AMOMENT said:
			
		

> Megan, a while ago MLEEK looked at some of my photos and suspected front focusing.  What would I do to fix this?  I'd prob have to send it in right?



Yeah you'd probably have to send it in. But I would do that focus test first.


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## Vtec44 (Apr 22, 2012)

I posted this http://www.thephotoforum.com/forum/...-here-few-i-enjoyed-cc-plz-2.html#post2569310 in your other thread...


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## KmH (Apr 22, 2012)

The second 2 have the childs face in a hard shadow. Auto focus needs light to detect edge contrast.

When shadows are hard like that where your your point of focus is, make sure the auto focus assist light is on.

Most of your issues are still a result of apparently not understanding how the camera and it's various systems work. Understanding Camera Autofocus
Your D3100 has a phase-detection auto focus system - Autofocus - Wikipedia, the free encyclopedia

Your 4 shot 'test series' were not done in a way that could yield you much in the way of useful information. As SCraig mentioned/alluded to, each of the focus points you used should have been put on exactly the same target in each photo, but weren't, which again indicates you have a long way to go as far as understanding how to use the camera's features, functions, and capabilities effectively as a tool for making photography.


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## zcar21 (Apr 22, 2012)

F7.1 for focusing test?? do it again with this setting. 
iso 100, aperture wide open, fast shutter speed.

Use central single focus point and point to the CONTRAST LINES. For example, look at the first picture of the girl. If you point at her right eye, you probably won't get focus there (it's in the shadow), but if you focus between her left eye and nose, your chances that the camera focuses there is more likely.


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## MTVision (Apr 22, 2012)

KmH said:


> The second 2 have the childs face in a hard shadow. Auto focus needs light to detect edge contrast.
> 
> When shadows are hard like that where your your point of focus is, make sure the auto focus assist light is on.
> 
> ...




Do you think the focus test chart (link in previous post) is an accurate way to do a focus test? I've never actually done the focus test (with that chart or a ruler) because I've never had any focus issues but I figured it would be more accurate then using a plant/child/whatever with a busy background. But then again, what do I know!


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## AMOMENT (Apr 22, 2012)

zcar21 said:


> F7.1 for focusing test?? do it again with this setting.
> iso 100, aperture wide open, fast shutter speed.
> 
> Use central single focus point and point to the CONTRAST LINES. For example, look at the first picture of the girl. If you point at her right eye, you probably won't get focus there (it's in the shadow), but if you focus between her left eye and nose, your chances that the camera focuses there is more likely.




Thanks =)  _I tried to point it at the eye that was closest to me. _


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## AMOMENT (Apr 22, 2012)

KmH said:


> The second 2 have the childs face in a hard shadow. Auto focus needs light to detect edge contrast.
> 
> When shadows are hard like that where your your point of focus is, make sure the auto focus assist light is on.
> 
> ...




I actually do understand how autofocus works.  For example, Passive AF system works very differently from active.  Instead of relying on infrared signal to find out the distance between the camera and the subject, it either uses special sensors within the camera to detect contrast  from the light that goes through the lens or uses the camera sensor itself to detect contrast in the image. This basically means that it tries to look for sharpness in a particular part of an image. If it is blurry, the AF system will adjust the lens focus until sharpness/contrast is achieved. That is why the Passive AF system requires that you have enough contrast in your frame for it to be able to focus properly. When a lens starts to &#8220;hunt&#8221; for focus on single color surfaces like white walls or gradient/blurry surfaces, it happens because the camera needs objects with edges (contrast) that stand out from the background to be able to acquire focus.There are also two types of AF sensors; vertical and cross type.  My Nikon has one cross type (the middle one) and the rest are vertical which detect contrast in a line.  The more cross type sensors you have and if you are using one, the better chance you have at being in better focus.  This is possibly why I have better results with my center FP especially, as mentioned, because I have atendency to have a shaky hand.

Grantid this is not a very in depth answer or a conclusive answer, but I didn't feel I needed to explain everything I understand.


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## AMOMENT (Apr 22, 2012)

Also, I know that this is how autofocus works; by detecting points of contras. I should be focusing on a point of highest contast nearest the point nd area i want in focus.  I really struggle with camera shake.  I think this might be making the problem worse.  Again, if I focus on the eyes and something VERY close (like a bright hair accessory) is there, it will often be sharper.


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## Vtec44 (Apr 23, 2012)

AMOMENT said:


> I actually do understand how autofocus works.  For example, Passive AF system works very differently from active.  Instead of relying on infrared signal to find out the distance between the camera and the subject, it either uses special sensors within the camera to detect contrast  from the light that goes through the lens or uses the camera sensor itself to detect contrast in the image. This basically means that it tries to look for sharpness in a particular part of an image. If it is blurry, the AF system will adjust the lens focus until sharpness/contrast is achieved. That is why the Passive AF system requires that you have enough contrast in your frame for it to be able to focus properly. When a lens starts to &#8220;hunt&#8221; for focus on single color surfaces like white walls or gradient/blurry surfaces, it happens because the camera needs objects with edges (contrast) that stand out from the background to be able to acquire focus.There are also two types of AF sensors; vertical and cross type.  My Nikon has one cross type (the middle one) and the rest are vertical which detect contrast in a line.  The more cross type sensors you have and if you are using one, the better chance you have at being in better focus.  This is possibly why I have better results with my center FP especially, as mentioned, because I have atendency to have a shaky hand.
> 
> Grantid this is not a very in depth answer or a conclusive answer, but I didn't feel I needed to explain everything I understand.



That's great!  But how do you apply this kind of information to attain focus and sharpness in your photos?


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## cgipson1 (Apr 23, 2012)

AMOMENT said:


> I actually do understand how autofocus works.  For example, Passive AF system works very differently from active.  Instead of relying on infrared signal to find out the distance between the camera and the subject, it either uses special sensors within the camera to detect contrast  from the light that goes through the lens or uses the camera sensor itself to detect contrast in the image. This basically means that it tries to look for sharpness in a particular part of an image. If it is blurry, the AF system will adjust the lens focus until sharpness/contrast is achieved. That is why the Passive AF system requires that you have enough contrast in your frame for it to be able to focus properly. When a lens starts to hunt for focus on single color surfaces like white walls or gradient/blurry surfaces, it happens because the camera needs objects with edges (contrast) that stand out from the background to be able to acquire focus.There are also two types of AF sensors; vertical and cross type.  My Nikon has one cross type (the middle one) and the rest are vertical which detect contrast in a line.  The more cross type sensors you have and if you are using one, the better chance you have at being in better focus.  This is possibly why I have better results with my center FP especially, as mentioned, because I have atendency to have a shaky hand.
> 
> Grantid this is not a very in depth answer or a conclusive answer, but I didn't feel I needed to explain everything I understand.



Nice cut and paste!!!  DSLR Autofocus Modes Explained   (I believe that is plagiarism, also! You didn't even bother to paraphrase it!)  ( I do love Google searches!)   



AMOMENT said:


> Instead of relying on infrared signal to find out the distance between the camera and the subject, it either uses special sensors within the camera to detect contrast











AMOMENT said:


> When a lens starts to hunt for focus on single color surfaces like white walls or gradient/blurry surfaces, it happens because the camera needs objects with edges (contrast) that stand out from the background to be able to acquire focus


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## zcar21 (Apr 23, 2012)

[video=dailymotion;x8lw9h]http://www.dailymotion.com/video/x8lw9h_plagio-plagiarism_shortfilms[/video]


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## cgipson1 (Apr 23, 2012)

zcar21 said:


> [video=dailymotion;x8lw9h]http://www.dailymotion.com/video/x8lw9h_plagio-plagiarism_shortfilms[/video]



I like that!


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## DiskoJoe (Apr 24, 2012)

AMOMENT said:


> I have a Nikon D3100 and often use either my 50mm 1.4 lens or my 55-300 f/4.8-5.6  My camera has 11 AF points but I have noticed that unless I use the central one (which has crosspoints) my focus is always blurry.  Even if I raise my aperture to increase depth of field and my distance from the subject.  (in some cases)  For this reason I often shoot af-s , lock focus, and then recompose.  I recently posted some pics in the People gallery and people said what I suspected, which is that my focus was off.  I don't necessarly understand why.  I am not shooting wide open, at least for now, to comopensate for my tendency to miss focus.  I almost never shoot with a shutter speed slower than 1/200.
> 
> When I shoot moving children I still usually shoot af-s and just hope for a still moment and snap quickly.  When I shoot af-c, I almost never get the shot because by the time my camera locks focus, the moment is over.  I am shooting single point but I wonder if I should be shooting dynamic for moving kids.  I suspect no because I generally want the child to be highlighted.
> 
> ...



Buy a tripod and set the camera on it and practice focusing on objects that are not moving. Inanimate objects are best because they will not move as you make adjustments to your camera.


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## Dom6663 (Apr 24, 2012)

When I started out shooting, my focus was pretty poor as well. However, then I switched to strictly manual focus (except for sports and snapshots). 

But still, consider turning your lens to manual, and focusing with your eyes and fingers. It can work miracles!


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## AMOMENT (Apr 24, 2012)

You're always ready to attack me, cgipson.  Give it a rest already.  If you're gonna just be a jerk to me, why bother even reading my posts?  Seriousely.  The REASON I included that info was not because I was trying to fool you but because after months of reading about focus, I had found that info to be the best explanation AND because it is what I interpreted and understood the best.  Therefore, I simply showed you what I understood.  I never said I wrote that info as my own.  I just explained what I understood about auto focus.  Since "this" is what I always refer back to in either my head or just as reference, why not include the wonderful EXACT explanation that taught me?


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## AMOMENT (Apr 24, 2012)

Thanks!!!  What about for shots with kids on the go?


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## AMOMENT (Apr 24, 2012)

cgipson1 said:


> zcar21 said:
> 
> 
> > [video=dailymotion;x8lw9h]http://www.dailymotion.com/video/x8lw9h_plagio-plagiarism_shortfilms[/video]
> ...



Honestly, you are just a bitter and sarcastic person.  (and not in the funny, dry wit type of way)  Instead of looking up shi* about plagarism why don't you do some google video shoots for "what an ass*ole does?"  It would be quite fitting =)  Heck, you wouldn't have to paraphrase either!


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## AMOMENT (Apr 24, 2012)

CIPSON, you are out to get me and personally, I don't care why and could care less about your input.  You are never helpful.  Please, do me and yourself a favor and just stay away from my posts.  They clearly bother you, so unless you are looking to argue or to pick on someone, there is no reason for you to entertain them.  I'm starting to think you pull this crap for attention and or to make yourself feel better about yourself.  SOOO...THERE YOU HAVE IT............no need to call me out; I need A LOT of work in photography, I have made and still make several mistakes, I decided not to go to the trouble to paraphrase the explanation of autofocus that made most sense to me (because I wasn't trying to take credit for coming up with the info, just for UNDERSTANDING IT)............but at the end of the day I know that I don't go around bullying people or being shi**Y!!!!


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## AMOMENT (Apr 24, 2012)

Vtec44 said:


> AMOMENT said:
> 
> 
> > I actually do understand how autofocus works.  For example, Passive AF system works very differently from active.  Instead of relying on infrared signal to find out the distance between the camera and the subject, it either uses special sensors within the camera to detect contrast  from the light that goes through the lens or uses the camera sensor itself to detect contrast in the image. This basically means that it tries to look for sharpness in a particular part of an image. If it is blurry, the AF system will adjust the lens focus until sharpness/contrast is achieved. That is why the Passive AF system requires that you have enough contrast in your frame for it to be able to focus properly. When a lens starts to hunt for focus on single color surfaces like white walls or gradient/blurry surfaces, it happens because the camera needs objects with edges (contrast) that stand out from the background to be able to acquire focus.There are also two types of AF sensors; vertical and cross type.  My Nikon has one cross type (the middle one) and the rest are vertical which detect contrast in a line.  The more cross type sensors you have and if you are using one, the better chance you have at being in better focus.  This is possibly why I have better results with my center FP especially, as mentioned, because I have atendency to have a shaky hand.
> ...




Well,  in my specific case, I would have to be aware of the areas of high contrast in my frame.  I would have to know that if I focus with a given sensor on something that is not of high contrast, it is possible it is not going to be as sharp.  I also have to know that if I use any of the other AF points other then the central one which has crosspoints, I prob need to increase my DOF.   Also, in areas of low light, it is not going to perform as well so I need to make sure I have enough light for the sensors of the AF system to detect.  It would prob be best to focus on the thing of greatest contrast nearest what I want to be my focal point.  Now....to just make this happen on a regular basis in my photos.  The photos I take with my center AF point (with the cross types) are not blurry...but I REALLY struggle to nail my focus with the other ones.


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## coastalconn (Apr 24, 2012)

Maybe I can help shed some light on this matter.  I have been around photo forums for awhile now, and I have found that most people think that there can never be a problem with the camera and it is always user error.  I know this because I just sent my D90 back to Nikon for a really bad back focus issue.  No matter what I posted people kept saying it was "user error".  The easiest way to confirm if it is really a front focus issue (which it looks like to me as well) is simply download a focus chart, shoot it on a tripod at a 45 degree angle on the center mark, wide open at base iso and center focus point.  If you have more then one lens try it with your other lenses as well. This chart clearly showed how badly my camera was back focusing. I shot it with many lenses and had the same result  DSC_8183.JPG  Once people saw this, the "user error" went away.


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## AMOMENT (Apr 25, 2012)

coastalconn said:


> Maybe I can help shed some light on this matter.  I have been around photo forums for awhile now, and I have found that most people think that there can never be a problem with the camera and it is always user error.  I know this because I just sent my D90 back to Nikon for a really bad back focus issue.  No matter what I posted people kept saying it was "user error".  The easiest way to confirm if it is really a front focus issue (which it looks like to me as well) is simply download a focus chart, shoot it on a tripod at a 45 degree angle on the center mark, wide open at base iso and center focus point.  If you have more then one lens try it with your other lenses as well. This chart clearly showed how badly my camera was back focusing. I shot it with many lenses and had the same result  DSC_8183.JPG  Once people saw this, the "user error" went away.



Thank you so much!  That was so helpful and I will do is asap.  =) Have a good night


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