Focus and re-compose

[lunas]

Hi Guys,

Will I lost sharpness if I Focus and re-compose?

Is it sharper to shoot at the center of the Focus area?

[zoossh]

Originally Posted by lunas Will I lost sharpness if I Focus and re-compose?

if you lock the focus properly and does not have significant change of distance from the subject, you will not lose the sharpness of a proper focus. in macro, distance need to be careful though, you move a little, the frame moves a lot.

Originally Posted by lunas Is it sharper to shoot at the center of the Focus area?

dun understand.

by the way, non-brand related questions is better answered in other parts such as the newbie or equipment subforum

[jmmtn4aj]

Depends on the depth of field. Your distance to the subject and aperture determine how deep the depth of field is. Recomposing at f/1.8 on a face 30cm away.. probably not a good idea, but the depth of field should be sufficiently deep for f/1.8 at >1m on a face. If you really have to go close, try smaller apertures.

[jnet6]

Remember to set your focusing mode to AF-S, not AF-C. else it will run with AF-C.

[lunas]

Originally Posted by jmmtn4aj Depends on the depth of field. Your distance to the subject and aperture determine how deep the depth of field is. Recomposing at f/1.8 on a face 30cm away.. probably not a good idea, but the depth of field should be sufficiently deep for f/1.8 at >1m on a face. If you really have to go close, try smaller apertures.

Thanks jmmtn4aj, you have nailed my question.

I was trying to shoot a toy at about 40cm away from the subject at f/1.4 with the 50mm lens. I focus and refocus again. The image becomes a bit OOF.

I am shooting at f/1.4 because I want the nice DOF.

1. So your suggestion is that I move further away from the subject / or use a smaller aperture.


2. BTW, does dynamic area focus help?

[Scaglietti]

What do you mean by "focus and refocus again"?

To focus on a subject that is not at the centre, there is a few ways of going about it.

First, you can use the choose a focus point that coincide with the subject. Focus and shoot.

Second, you can use centre focusing point or any focus point (if they do not exactly fall on the subject). Place the focus point on the subject by half-pressing the shutter release. Re-compose while holding onto the shutter release (you will loss focus lock if you releasing it and it will refocus on the wrong subject if you recompose and press it again). Fully press the button after recomposing.

Third, you can use your AE-L/AF-L lock button for focus lock. Configure it accordingly via your menu (check you manual). Use it for focus lock.

Fourth, you can also configure the AE-L/AF-L button for Focus on. That means instead of half-press for focusing, you use the AE-L/AF-L button to activate focusing. This is good if you want to take multiple shots after focusing and recomposing. You do not have to move your focus point get focus lock and then recompose after each shot.

BC

[zac08]

Originally Posted by lunas Thanks jmmtn4aj, you have nailed my question. I was trying to shoot a toy at about 40cm away from the subject at f/1.4 with the 50mm lens. I focus and refocus again. The image becomes a bit OOF. I am shooting at f/1.4 because I want the nice DOF. 1. So your suggestion is that I move further away from the subject / or use a smaller aperture. 2. BTW, does dynamic area focus help?

Check the lens minimal focusing distance. You may be too close.

Shooting at f1.4 gives you a VERY thin DOF esp when it's close by. You may want to use a tripod to keep the camera steady, else use a smaller aperture as suggested like f2.8 or f4.

[Noakram]

Maybe this link on DOF calculation might be useful for you. I was just asking myself about this 2 hours ago.

http://www.dofmaster.com/dofjs.html

[spazzer]

Originally Posted by lunas Hi Guys, Will I lost sharpness if I Focus and re-compose? Is it sharper to shoot at the center of the Focus area?

definetly better to shoot withing not say center cannot

[zac08]

Originally Posted by spazzer definetly better to shoot withing not say center cannot

What are you trying to say??