Geoff Schultz wrote:

"J. Clarke" wrote in
:

Grant Erwin wrote:

I often want to shoot a picture of some detail just to post it as an
adjunct to a discussion, as "a picture is worth a thousand words". I
have terrible trouble shooting closeups with digital cameras. I have
finally found the method that yields the best results:

use minimum aperture for max depth of field (f2.8)

Whoa. That would be the _maximum_ aperture on most digitals. Minimum
would be down around F/8 or F/16. That might be part of your problem.

The maximum aperture is when the lens is all of the way open (lowest F
number) and provides the minimum depth of field. When the lens is at the
minimum aperture (highest F number) you get the maximum depth of field.

Typical full f-stops are numbered:

1.4 2.0 2.8 4 5.6 8 11 16 22

Are you trying to clarify or to disagree? I can't tell.

Very few digitals other than interchangeable lens SLRs have apertures above
2.8--a digital set on 2.8 is generally wide open.

and for every F-stop increase you halve the light reaching the
film/sensor. That means that you need to increase either the flash power
or the exposure. You probably don't want to increase the exposure as you
can introduce camera shake which will blur your photos.

Yes, with macro photography you _do_ want to do that--insufficient depth of
field will blur your photos for sure but camera shake you can deal with
either with a good tripod or with a firm brace.

-- Geoff

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)