is back and front focussing issues something i should be concerned with OR

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SsSsSsSsSnake

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should i just concentrate on learning how to use my camera in the best possible way to maximize sharp focus and good composition etc.

keep reading about people having issues with this and making micro adjustments to maximise lens body combo.not something which all cameras have though.

I feel I'm jumping ahead of myself rather than learning how to minimise focus problems.

Just my nature is such to read on all this stuff,then look for problems that probably don't exist in the 1st place:)
 
Is it a d7000?
 
If your camera has the facility for it then have a look at doing it,at least you will know focus errors are yours not the cameras
 
The d7k is prone to it
 
Problem is people hear about these issues and then go looking for it. It was quite obvious with a d7000 I had when using a 70-200. When I changed to the d7100 the 70-200 was a revelation, absolutely perfect focus.

If you focus on a static contrasty subject using single focus point, continuos servo with a reasonably high shutter speed to ensure it's not camera shake then it should be obvious if there is a focus problem.

I would concentrate on learning to get sharp photos as there is lots that affects focus/sharp photos, don't go looking for problems that may not exist. Shutter speed, focal length, aperture, subject movement, focus mode, number of focal points , hand holding technique all affect the focus or sharpness of the photo. If you have focus/sharpness issues post images on here with exif data and there are plenty of people who can help.
 
Hi guys thanks for the replies,i have a D3300 and i think I've realised it was subject movement,the wind was blowing the blossom slightly as i was taking the photo,thats what I mean I need to understand all the basics first,

just took some more pots and very pleased with them,using some of the tips from here.
thanks
 
rob-nikon said:
Problem is people hear about these issues and then go looking for it. It was quite obvious with a d7000 I had when using a 70-200. When I changed to the d7100 the 70-200 was a revelation, absolutely perfect focus.

If you focus on a static contrasty subject using single focus point, continuos servo with a reasonably high shutter speed to ensure it's not camera shake then it should be obvious if there is a focus problem.

I would concentrate on learning to get sharp photos as there is lots that affects focus/sharp photos, don't go looking for problems that may not exist. Shutter speed, focal length, aperture, subject movement, focus mode, number of focal points , hand holding technique all affect the focus or sharpness of the photo. If you have focus/sharpness issues post images on here with exif data and there are plenty of people who can help.
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Rob you've summed me up well,i know I need to learn all those things first before I go looking for problems that probably don't exist :). cheers
 
stumeech said:
If your camera has live view then try focussing in that as the camera will be focussing off what the sensor sees and it won't get any sharper than that.
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Stu so does this mean that when focussing through the viewfinder you are are focussing off the mirror image? and just for completeness sake,say someones lens body was off and they used live view that would give infocus shot even yet if one was to have looked through the viewfinder it would have looked out of focus,and reversibly if say another shot looked in focus through the viewfinder if you swapped to live view that would look out right?
 
When focussing through the viewfinder the camera uses phase detect which is housed in the bulge on top of the camera andh because it isn't the exact same place as the sensor there can be some discrepancies - this is where front/back focussing issues come from. The benefit of this though is that it is much faster and has better prediction of where moving subjects are going.

In live view the camera focusses using contrast detect sites on the actual sensor and because it is using contrast to determine best sharpness at the sensor the images are guaranteed to be in focus (assuming it can acquire focus).

So, if you mount the camera on a tripod and take images using the two different methods you can see how accurately tuned your AF is. However, I wouldn't recommend it as there are a number of other factors which come into play - not least that it is lens dependant and it could be the lens that is out.

My view is that if it is front/back focussing to any significantly relevant amount it will be obvious in every shot and you'll quickly realise. Most of time it's user error.

I've owned 5 (I think) Nikon DSLRs and only one of them has had a focus issue.
 
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With A D3300 you do not have the facility to micro adjustment so I would suggest do not worry.
 
thanks for that explanation Ned,i understand ia lot better now and mark yes that was my concern if it was out but its only a few shots and I'm certain its my fault by not being more careful in all the choices i make in the shot.most of the photos are really sharp.
 
Whenever you have the time to push for maximum detail resolution, e.g. you're photographing a building using a tripod, take a shot using AF, and another one or two using the best manual focus you can manage. Over time this will show you the areas of lens performance where you can trust your AF, and those where you can't.

Generally speaking at apertures from f4 and smaller and focal lenghts from 25mm to 150mm AF is usually fine. Problems sometimes arise with wide angle lenses, with apertures wider than f2.8, the longest end of wide range zooms, very close photography and macro, and focal lengths over 200mm. Those are the areas where finical high resolution photographers most often drop AF and switch to manual focus.

It varies a lot between different lenses, different versions of AF, and different combination of bodies and lenses. In other words, you do have to learn how the particular kit you've got behaves.

I have an 18-250mm general purpose zoom which was always a bit soft at 250mm. All the reviews said that was how it was, so I simply put up with it as one of the compromises of a wide range zoom. Then I acquired a 500mm with razor sharp DoF which was obviously back focusing a bit. It was so hard to focus the 500mm manually that I adjusted the camera's AF to get the 500mm lens spot on focus. To my surprise I found that 250mm on my 18-250mm also sharpened up! I'd never noticed it was misfocusing there before because so many of my 250mm shots were fuzzy for other reasons, such as camera shake, thermal turbulence in the air, high ISO, etc..

Don't fuss too much. Nothing's perfect. Just arrange your shoots to contain the occasional focus checking experiment where convenient and you'll gradually learn the AF weaknesses of your camera and lenses. Generally speaking they only matter in certain specific areas of lens use, and then only when you're being very fussy.
 
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