Tips for improving focus. ??

[AMOMENT]

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?

 

[MTVision]

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.

 

[Vtec44]

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

 

[KmH]

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.

 

[zcar21]

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.

 

[MTVision]

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.

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!

 

[AMOMENT]

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.

 

[AMOMENT]

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.

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.

 

[AMOMENT]

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.

 

[Vtec44]

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.

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

 

[cgipson1]

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!)

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

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

 

[zcar21]

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

 

[cgipson1]

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

I like that!

 

[DiskoJoe]

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

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.

 

[Dom6663]

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!