higher than f11

[steve_m]

I thought I read on an earlier post about image quality dropping if you use an fstop higher than f11. Can someone shed some light on this subject. I can't seem to find it when I do a search on this forum.


Thanks,


Steve

[Oren]

Search for DLA (not just on this forum).

[Jon Ruyle]

Hi Steve,


Whenever light passes through an aperture, it blurs. That is, the image of a point becomes something like a disc. The smaller the aperture, the bigger the disc, ie the worse the blur.


When is smaller than a pixel, you don't tend to notice. Ie, when the f number is smaller than the dla, you don't have any reduction in image quality.


Hope that helps.


Jon.

[hotsecretary]

By higher, you mean lower?

[ShutterbugJohan]

By higher, you mean lower?

Could you clarify your statement? I think that what he means by "higher" is a larger f-number (i.e. f/16, f/22), and not a larger aperture diameter (i.e. f/2.8, f/4).

[hotsecretary]

Well, that's I meant.. lower number aka larger


I'm now confusing myself, but I can see that as you want a higher f-# if you want it to be more in focus...

[Jon Ruyle]

This article explains things much better than I did. You might want to take a look


http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm