Comments on: So You Think You Know What An F-Number Is

By: bridal shower games

bridal shower games — Fri, 13 Jun 2008 09:02:37 +0000

i never like math but reading your post makes me want to love it again

By: red heart yarn

red heart yarn — Thu, 12 Jun 2008 13:56:43 +0000

u remind me of my math lecturer lol

By: Brian Auer

Brian Auer — Mon, 05 May 2008 00:41:56 +0000

The crop factor does change the depth of field. Here’s an online DOF calculator that you can use to see the differences between digital and film cameras. I couldn’t really tell you why though without doing a little more research on the subject.

By: Mirko CRO

Mirko CRO — Sun, 04 May 2008 22:38:12 +0000

Thanks!

I get it. Just one more thing - does the crop factor affect depth of field (and how if it does)?

By: Brian Auer

Brian Auer — Sun, 04 May 2008 17:04:21 +0000

Good Question!!! The crop factor on a digital camera has nothing to do with the lens’ f-number, real focal length, and aperture diameter. The increase in focal length is only an equivalent value — it’s not actually giving you any more magnification (check out this article where I did a comparison between a digital and film SLR equipped with 50mm lenses).

So if you have a 50mm lens (for a film or digital camera) and you set the f-number at f/1.4, your aperture diameter is 35.7mm.

By: Mirko CRO

Mirko CRO — Sun, 04 May 2008 11:25:13 +0000

Great article!

I have one question regarding aperture: How does all this relate with crop factors of an DSLR camera?
If i have camera with crop factor of 1.5 and a 50mm f/1.4 lens. Does that mean that my f number isn’t 35.7mm (50/1.4) but 53.6mm (50*1.5/1.4)?

“the f-number is a measure of lens speed — regardless of the camera, regardless of the lens, and regardless of the conditions.”

Would that mean that this statement isn’t true?

By: First DSLR Buying Guide - Matthew Botos

First DSLR Buying Guide - Matthew Botos — Sat, 26 Apr 2008 19:31:52 +0000

[...] I’ve found that ambient light can only take you so far - even with a “fast lens” (f-numbers and the nonlinear reason that f2.8 costs twice as much as the f4). Indoors, at night, or if you [...]

By: göğüs büyütme

göğüs büyütme — Wed, 02 Apr 2008 07:46:55 +0000

Very informative article about F-stop and aperture relations. This is the basics of photography everybody should memorize.

By: burun

burun — Tue, 05 Feb 2008 09:30:07 +0000

Great blog page. Thanks a lot for the information.

By: Alan Cook

Alan Cook — Sun, 27 Jan 2008 11:20:19 +0000

Awesome. You make my understanding of F-number look like a joke.

Thanks for the great information.