Re: Why increase F number

On Jul 28, 8:13 am, "dadiOH" <dad...@xxxxxxxxxxx> wrote:
Charles E Hardwidge wrote:
"PatM" <gro...@xxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:a0d959e8-f9f6-41e4-b33d-d63095697420@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Some of the responses, above, are okay but not great.  The problem is
with your question.  It assumes that (a) there is a "right" aperture
or (b) a higher number is somehow inherently better.

That reminds me. In The Complete Guide to Professional Wedding
Photography, by Damien Lovegrove, he comments that he *always* shoots
with F/4. This is what he was taught while he was a trainee cameraman
for the BBC. The reasoning is that it's the ideal aperture for
maintaining a consistent look across shoots that might last several
weeks under different lighting conditions. He figured a similar
principle operated with day long wedding shoots. Does anyone have any
comment on that?

Yes.  It's silly.

Firstly, f4 with what size film and what focal length lens?  If, for
example, one were using 6x6cm film and a 75mm lens, f4 would give an
entirely different effect than if one were using a 250mm lens at that
aperture on the same camera.  Photographers *do* change lenses from time to
time.

IIRC, and I'm doing this from 30 years of memories, if you frame the
same subject in exactly the same way using the same f/stop, your DOF
is the same in both cases. So if you use a 50mm lens to frame a
subject and then frame the same subject in the same way with a 300mm
lens, you get the same DOF at the same f/stop. The difference, of
course, is your relative position to the subject. Also, of course,
you'll get the that compressed look from the 300mm that you won't get
from the 50mm if it is up close.

That is why, again IIRC, it seems like telephotos have shorter DOF.
If you frame something with a 50mm and the DOF is 2'; that seems like
more DOF than if you do the same framing with a 300mm and the DOF is
2' because you are so much farther back with the 300mm.


Secondly - even if the same lens were used throughout the day - photographs
close up will look "different" than those at a distance...those close up
will have a fuzzed out background, those at distance will not.

One chooses the aperture according to the effects desired.  Those who can,
do; those who can't, write books.

--

dadiOH
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