A Quick (Very) NOOBISH question

[703Methane]

Ok So since I can't really get this i'm going to have to ask TPF. So the other day during my independent study in school.. Me and two friends went out the back of my school, So I could practice, as they just wanted some new facebook pictures i gues.. idk lol

But heres my issue Aperture... So Here the photo

Now for the guy in the back Is out of focus... For me I thought it was just if you open the aperture up more things get in focus around the focal point... Now with that dumb theory in my head i get results like this..:meh:

So let me get this straight, shooting auto focus, with the red focal points popping up. IF I hit my shutter button half way down that locks the focal point. Now once I lock one, I would have to lock another in order to get the Second subject in focus? And what about 3 or more subjects in the picture?

I really want to get this, so I don't get more results like these..

Thanks,

 

[o hey tyler]

What you need to do is use a smaller aperture to get both of their heads in sharp focus. Try shooting on f/7.1 or f/8. There's no way that you can stretch a focal plane while using a large-ish aperture.

 

[703Methane]

And an other question how do i remove my exif data ?!

 

[703Methane]

What you need to do is use a smaller aperture to get both of their heads in sharp focus. Try shooting on f/7.1 or f/8. There's no way that you can stretch a focal plane while using a large-ish aperture.

So its just the fact that my aperture wasn't small enough ?

 

[o hey tyler]

What you need to do is use a smaller aperture to get both of their heads in sharp focus. Try shooting on f/7.1 or f/8. There's no way that you can stretch a focal plane while using a large-ish aperture.

So its just the fact that my aperture wasn't small enough ?

Yes aperture and focal length are the two determining factors in depth of field.

Why would you want to remove your EXIF data? That's how I was able to tell what you were doing wrong.

 

[703Methane]

My photoshop... The whole ' Cutoff branch' thing...

But alright Aperture needs to be smaller, and Focal length .. I will keep that in mind for tomorrow.

Thanks a lot Tyler, I'll see if i can get some better results !

 

[KmH]

There are focus modes that will use more than one focus point for a single exposure, but all of those focus point have to be the same distance from the image sensor and in a plane that is parallel to the image sensor.

Further, focus and depth-of-field (DOF) are tied together. Depth-of-field determines the depth of the zone that will be likely be in acceptable focus. The front and rear of that zone are also parallel to the image sensor plane.

DOF is a controlled by 4 variables:

1. the lens focal length
2. the focus point to image sensor distance
3. the lens aperture
4. the focal point to background distance.