Rushing so super brief (for me).

Much good advice. Quite a lot of what Olin said was quite good and as he
didn't know what you knew he over-explained things for your level of
knowledge. I think that your response will probably ensure that he won't do
that again. His suggestions re the camera attempting to increase sensitivity
may well be right and his comments re bright sunlight are also good.

His comments on std f numbers used was correct and almost invariably what
was used with film. Some digital cameras use random f stops and shutter
speeds which annoys long time photographer brains - like eg mine.

Knowing what camera you are using and what lens (if separable) would be
useful.

Knowing light source and intensity also helps.

Depth of focus can be calculated for a given aperture and distance. Gargoyle
knows. (Too rushed ot I'd dig it up).

There will be an optimum point part way along the length to centre your
focus on for best result. Probably / maybe at the geometric mean distance.

If I was doing this I'd us widest aperture where diffraction was not a major
factor. f 1:22 is usually OK. f 1:16 certainly so (with APSC DSLR - I think
this translates directly with other systems but may need to think more on
that).

Higher ISO will produce more noise. Camera may "ISO up" automatically.

Shutter speed will drop as aperture increases for given light level.
It's easy to drop into areas where shake matters. You are probably using a
tripod but just in case - use a tripod.

If the camera and/or lens has anti-shake and you are using a tripod, turn
the anti-shake off - the servo tries to hunt for noise and there is none but
it effectively makes some.

For a given aperture shorter focal lengths and closer up should give more
depth of field than further away and long focal length to compensate.

If this were I, I'd start at:

1. Play:
- Brightest light. Sun is 100,000 + lux on good day. Photofloods usually
less.
- Low ISO <= 200. Lower possibly.
- f22 to start
- tripod
- antishake off.
- focus near geometric mean.
- play with focal length.

Similar shots at f 8 11 16 22 32 should see depth of focus improve up to
f16, probably Ok at f22, odds are f32 will be diffraction affected.

2. Calculate what theory says I SHOULD be able to achieve (after having
failed :-) ).



            Russell
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