Tips for improving focus. ??

[AMOMENT]

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?

 

[AMOMENT]

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

 

[AMOMENT]

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

I like that!

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!

 

[AMOMENT]

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!!!!

 

[AMOMENT]

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?

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.

 

[coastalconn]

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.

 

[AMOMENT]

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