How to make the most of my focus points?

JustJazzie · Mar 12, 2015

This is such a basic question that I am almost embarrassed to ask it.

Long ago, I used to center point focus and recompose. Not so awesome.

Then I went to mirror-less, and I always moved my focus point to the eye. Great focus, but takes quite a bit of time.

Well, with my nikon I always end up using the closest focus point I can, stick it on the eye/or my subject and shoot. Then I end up cropping quite a bit more than I would like to for composition. If I have time, I throw it into live view and use it like my sony so I can get the focus right where I want it.

But I sit here and wonder- Is there a better, more efficient way to use my Af points, without sacrificing all the pixels that I am cropping out?

If there is already a thread that you know of that will answer this, please link me!

Derrel · Mar 12, 2015

I do not see any connection at all between the focus point or points that were used to take an image, and what might or might not end up being cropped out.

As far as AF systems go: they have become very complex, and very capable. There is auto-area AF, where you allow the camera to select the subject, and there is manual AF point/AF-area selection, with focus tracking; and variations, plus single-point, 9-point,11-point, 21-point, 39-point, and 51 point,depending on the Nikon model you happen to be using. There are a number of camera setup choices that affect how focusing will be done. It can be a very complicated subject.

There is not a whole lot written on AF operation. Thom Hogan's web article and camera reviews touch on focusing issues. I think it is something a person needs to figure out for herself, with her own camera and her own shooting situations. My experience is that there is a LOT of misinformation, and a TON of people who say stuff like, "Just use the central AF point, and make due with that...because that's all I have ever done!"

JustJazzie · Mar 12, 2015

@Derrel Hmm. Maybe I didnt phrase my question well. Say I am shooting a portrait on single point AF. I want them far to the left and towards the top. I have no Focus point there because their eye is outside of my optional focus points. So I use the one on the top left corner, but the person isn't where I want them any more and I crop out the entire top left in post to bring the person back to where I want their eye. Does that make sense?

I think I understand focus MODES, and when to use them. But what do DSLR users do when they don't have any focus point's where they want it? Is focus and recompose not as bad as I remember it? were my recomposing methods just not up to par?

ronlane · Mar 12, 2015

Using focus locking and then recomposing is what would need to be done to get the composition that you want. (If you don't have enough AF points.)

For me personally, this is one instance where back button focusing really pays off for me.

runnah · Mar 12, 2015

So are you shooting super wide open? I know folks always like to do this but it makes the dof so thin that you get out of focus noses and ears. If you shooting around the 2.8-3.5 range you have a much larger margin for error. THis way you don't have to be locked into the eye, rather you can focus on their nose/mouth etc...

ronlane · Mar 12, 2015

I agree with runnah about not shooting wide open to help the face be in focus, but I disagree about not having to lock on the eye. When shooting a portrait, I want the eye to be tact sharp, so I lock on the eye and recompose as needed.

Braineack · Mar 12, 2015

i lock on wherever, and use an aperture that makes the DOF wide enough that the entire face is in focus

JustJazzie · Mar 12, 2015

ronlane said:
Using focus locking and then recomposing is what would need to be done to get the composition that you want. (If you don't have enough AF points.)

For me personally, this is one instance where back button focusing really pays off for me.

I tried to like BBF, but just never got the hang of it. Perhaps I should give it another try.

runnah said:
So are you shooting super wide open? I know folks always like to do this but it makes the dof so thin that you get out of focus noses and ears. If you shooting around the 2.8-3.5 range you have a much larger margin for error. THis way you don't have to be locked into the eye, rather you can focus on their nose/mouth etc...

Hypothetically speaking, yes. Shooting open. It isn't a habit of mine, but I would like to have a good technique for when the need arises.

ronlane said:
I agree with runnah about not shooting wide open to help the face be in focus, but I disagree about not having to lock on the eye. When shooting a portrait, I want the eye to be tact sharp, so I lock on the eye and recompose as needed.

So is focus and recomposing from the closest AF point going to be significantly more accurate than say, using center point? (Yes yes, Jazzie- go shoot some pictures and figure this out for yourself- easier to do when you have a computer that turns on and isn't as slow as a snail)

Braineack said:
i lock on wherever, and use an aperture that makes the DOF wide enough that the entire face is in focus

;-) We cant all be braineacks. ;-)

ronlane · Mar 12, 2015

JustJazzie said:
ronlane said:

Using focus locking and then recomposing is what would need to be done to get the composition that you want. (If you don't have enough AF points.)

For me personally, this is one instance where back button focusing really pays off for me.

Click to expand...

I tried to like BBF, but just never got the hang of it. Perhaps I should give it another try.

ronlane said:

I agree with runnah about not shooting wide open to help the face be in focus, but I disagree about not having to lock on the eye. When shooting a portrait, I want the eye to be tact sharp, so I lock on the eye and recompose as needed.

Click to expand...

So is focus and recomposing from the closest AF point going to be significantly more accurate than say, using center point? (Yes yes, Jazzie- go shoot some pictures and figure this out for yourself- easier to do when you have a computer that turns on and isn't as slow as a snail)

BBF does take some time to get use to it.

Yes, using the closest AF point will be more accurate due to the distance change caused by moving the camera. (Even if it is only slightly, it is still changing the distance from the sensor to the subject.)

Derrel · Mar 12, 2015

Focus and recompose works reasonably well as long as the magnification is low, or the distance is not too close; the closer one is, the more-critical focusing becomes. If the depth of field is less than the margin for error, focus and recompose will fail at times. If the lens has a lot of field curvature, the focus could be "off" at the edges and on in the center, or vice-versa.

I dunno...I like to have just a little bit of "cushion", a bit of leeway for focusing errors and subject movement and so on. If I can, I usually shoot photos of people at f/5.6 or f/ 6.3 or f/7.1. Working in that general range gives me enough DOF to get the look I want. I do not like out of focus noses, and one-eye-in, one-eye-out focusing...it just does not appeal to me.

weepete · Mar 12, 2015

I must admit I tend to use about 9 AF points on my camera and I tend to be in single point AF all the time with BBF.

If a point where I want focus is not near any of my AF points I will focus recompose.

The focus recompose method is useful, but as others have mentioned it is only useful if you are able to keep an eye on your DOF and compensate for the corresponding change in the angle of DOF.

Vtec44 · Mar 12, 2015

Focus plane is the key. You can focus on anything on that same plane, and everything on that same plane will be in focus. Since Nikon AF points tent to be bunched up, I use focus plane to estimate focus a lot. I use center focus point 99.87% of the time and shoot between f1.4-1.8 98.66% of the time.

Mega Jones · Mar 18, 2015

JustJazzie said:
This is such a basic question that I am almost embarrassed to ask it.

Long ago, I used to center point focus and recompose. Not so awesome.

Then I went to mirror-less, and I always moved my focus point to the eye. Great focus, but takes quite a bit of time.

Well, with my nikon I always end up using the closest focus point I can, stick it on the eye/or my subject and shoot. Then I end up cropping quite a bit more than I would like to for composition. If I have time, I throw it into live view and use it like my sony so I can get the focus right where I want it.

But I sit here and wonder- Is there a better, more efficient way to use my Af points, without sacrificing all the pixels that I am cropping out?

If there is already a thread that you know of that will answer this, please link me!

To get the right composition you need to use focus locking and then recomposing to get the composition that you want. In these kind of cases, back button focusing really pays off for me & it's a personal experience.

astroNikon · Mar 18, 2015

JustJazzie said:
I tried to like BBF, but just never got the hang of it. Perhaps I should give it another try.

I went to a soccer game and practiced BBF & lock alot. I tested it shooting the Ball (not the players). So catching a ball meandering around the field you do a quick BBF & lock as it screams across the field.

You get used to it fairly quickly then as you can't keep a focus point on the ball.
and Auto focus likes to get the players, grass, background, sky, your shoelaces, a cat in the distance playing with a ball of yarn and stuff like that .. but never the ball.

KmH · Mar 18, 2015

It's likely not all of the focus points in your camera are equal.
Some are more accurate cross-type focus points.
When I have them I only use cross-type focus points.

For shooting people, I used single point focus and focus/recompose if necessary.
I used dynamic focus, only the cross-type focus points, and BBF to shoot action sports.