Aperture Question

[kric2schaam626]

I have been reading a lot lately that to have an "even" amount of focus on a subject requires the aperture to not be too high. I find myself going to the max aperture and higher shutter speeds to balance the light. I apologize for not having an example photo, but I am just coming around to the possibility that it's not right?

With a lower aperture, is there a better focus in a picture with good lighting?

I can find an example picture if necessary.

Thanks so much!

 

[sierramister]

Yes. With an aperture below 4, the range of distances from the lens is harder to get a desirable focus. If you had two subjects in your photo and the distance from the lens to the face of subject A is 3m and the distance from the lens to the face of subject B is 3.2m, you would have trouble getting a good focus on both of them. If you above f/8, the distances from lens to A and lens to B doesn't matter as much.

 

[kric2schaam626]

Yes. With an aperture below 4, the range of distances from the lens is harder to get a desirable focus. If you had two subjects in your photo and the distance from the lens to the face of subject A is 3m and the distance from the lens to the face of subject B is 3.2m, you would have trouble getting a good focus on both of them. If you above f/8, the distances from lens to A and lens to B doesn't matter as much.

That explains a few things! :neutral: It might be a hard habit to break, I have this train of thought that if there isn't enough light, add on the aperture and if I can't, lower the shutter!
Thanks for your help.

 

[myshkin]

i recommend putting your camera on a tripod focusing on a subject 4-6ft away and put the camera on aperture priority mode. Then shoot at each f stop and then look on computer and compare to visually see the difference.

 

[Patrice]

Your d80 has a depth of field preview. Takes a few times to get used to it and the viewfinder gets a dark at smaller apertures. Not really necessary if you enlarge your image on the review lcd and check critical focus.

 

[Dominantly]

I suggest you play with this then come back for clarifying questions.
Online Depth of Field Calculator

 

[The_Traveler]

This question and the answers are posed in a sort of inverted way.
Here is the way I like to think about it.
_________________________________________________________
There are four issues you have to balance when taking portraits

1) The Depth of Field of a lens generally increases when the aperture gets smaller. Thus the DOF is very narrow at f 2.8 and much greater at f16
2) Most lenses, except the very expensive pro glass, have a sweet spot where the image is much better and that sweet spot is usually 2 or 4 stops from the maximum opening. (you should know that, or find it by testing, for your own lenses)
3) At very small f stops (f16, f22) many lenses start to get blurred images because of diffraction issues.
4) When taking portraits, it is usually a good idea to use the smallest f stop you can to isolate the subjects from the background.

Thus, I take portraits at the largest f stop (largest opening) I can where I can get every important part in focus and still isolate the person from the background.

I use a DOF calculator to get a good idea of what the DOF is for any specific lens, f stop and distance to the subject.

Since the subject's eyes are the most critical part of any portrait, I try to focus on the subjects and let everything else work itself out.

 

[DiskoJoe]

this would be easier to advise you on if you showed a shot that did not come out how you wanted and then you explain what you did want.

 

[LarissaPhotography]

I find when I set my aperture to 1.4 or 1.8 that I miss frequently - especially with a moving target. Somewhere close to 2.5 works out better for me to make sure I don't miss my focus point.

 

[The_Traveler]

It's a losing cause to try and shoot a moving target at f 1.8. The DOF is so shallow that you'll never get a good shot and its doubtful if AF would work well.