catalint wrote:
Hi fellow hogs,
For a while I have had this challenge regarding focusing correctly. This is not a matter of "how-to", but rather "What Am I doing wrong?". Yes I've been googling, and watched this and that, but I can't get answers from that. So I hope a good eye here can see what's wrong.
Case is like this. Dont remember exactly when I did, but like 2 years ago, I started using single focus point. Also my camera is mostly on M-mode. Camera is on AF-S most of the time. Sometimes I switch to AF-C when lot's of motion. Ofte I need to move the focus point a little to the left , right, up or down, depending. Having one single object as subject, I have no problems, but I am not happy with pictures where I have like two three persons in the picture. One persons will be focused, the other one is slightly out of focus. For me it looks like single point focusing has a very small radius. Let say you have 3 persons in the frame, you point in the middle, focus and shoot. While the middle will be in focus and sharp, it gets less sharp further from the center. I know AF-S should be used with dead stationary objects, I read it somewhere. Does this mean one should switch to AF-C as soon as you have a little movement ? Like my little niece in the picture below. She is actually in movement since my sister is swinging her. but it wasn't fast.
So how do you focus, correctly for the whole frame with single AF point?
Below is a picture to show you what I mean. My sister and one of my nieces, taken yesterday. I was like 10m away from them, and took this picture at full zoom from my 24-120mm Nikon F4.5. My sister is looking good and sharp (could have been better also in my opinion), while my niece is a little blurred. From the exif data I see I should have probably raised up the shutter speed a little more, and maybe I would have had both as sharp? Or is it cause my camera was back focusing on my sister? I can't determine if this it's clearly from low shutter speed or wrong focusing system.
What settings would you fellow hogs have used in this kind of situation ? I know lot's of you also swear to single focusing point, so I hope to hear if you encountered this problem. I do not think there is something wrong with the equipment, it has to be ME. I need to improve.
Hi fellow hogs, br br For a while I have had thi... (
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You shot your image at 1/200th sec @ F/7.1 and ISO 500.
SHARPENINGOne requirement for all digital images is sharpening, usually done in-camera by point and shoot cameras. In DSLRs most often the sharpening is turned off so that sharpening is required in post processing where there is more control. If you shoot in RAW there is no in-camera sharpening.
The first image here clearly shows the need for some sharpening in post.(see Image 1)
CAMERA/SUBJECT MOVEMENTWith your lens set at 120mm, the 1/200th sec would be
about right for a stationary subject, to prevent blur from camera movement . . .
but as soon as you add subject movement to the mix, a faster shutter speed would be required. Image 2 here shows the subject movement on your niece, and no subject movement on your sister. If you look at the close up of the necklace (Image 3) you can clearly see the double image . . . subject movement.
MOST out of focus images taken today are in fact
NOT out of focus, but suffer from camera/subject movement. This is especially true when shooting in Auto modes.
DEPTH OF FIELD (DOF)Your problem here is definitely
not one of DOF !
At F/7.1 with the focus point on your niece, your sister would also be in focus. (which in this case she is)
The apparent lack of sharpness in your sister in this image is caused by slight under exposure of the area and lack of contrast of light hitting the subject.
This is an ideal situation for fill flash set at about -1 stop compensation or a reflector.
THE ART OF FOCUSING AN AF LENS/CAMERAFew understand how the auto focus system works and, as a result, use it incorrectly.
At 10 feet from a subject, it is impossible to focus on a subject's eye. The camera focus area is more than the size of the head at that distance so the camera will choose the brightest object with the most contrast on which to focus within that area. (See Image 4) This item could be 10 feet behind the subject.
If there are objects close to the area on which you wish to focus, that could draw the attention of the focusing pixels on the sensor, it is probably better to pick another spot on which to focus that is the same distance from the camera as the desired focal point. (see Image 5)
Every picture taken should be a three step process . . .
focus by pushing the shutter release halfway and holding . . .
recompose . . .
fire by pushing the shutter release button the rest of the way.
Hope this helps . . .