At 13.03 25/02/2010 +1100, you wrote:

> > Remember to use a tripod or macro mount (modified enlarger stands are
> ideal)
> > and use the highest f-stop possible to maximize depth-of-focus (this will
> > make for long exposures, necessitating a stable stand to avoid
> > camera-shake).
>
>__ By all means, heed Andrews's advice here... AND use the delay shutter timer
>so that the camera has time to quiet down after your hand leaves it. In this
>sense, CCD-digital cameras rock!... no moving parts to shake the camera.

Maybe I am a little bit late, anyway:

- I would not advise to use the highest f-stop, but to use the f-stop at
which the lens has the best resolution.
This generally happens around f/8, but any lens has its behaviour.
To see tests with lens resolution you may visit sites like: www.photozone.de
see for example the Canon 100 mm macro which gave me a lot of satisfaction:
http://www.photozone.de/canon-eos/167-canon-ef-100mm-f28-usm-macro-test-report--review?start=1
As you can see from istograms, the lens resolution decreases a lot at high
f-stop because of light diffraction.
I have seen this being particularly evident when using my camera mounted on
a microscope which had f regulation, but also with standard lenses there is
a visible effect, try it taking pictures of the same subject with the same
lens at the same light conditions but with different f.
The slight decrease in depth-of-focus can be overcome with softwares like
CombineZ while low resolution can't be overcome.

- I would also advise to use remote shutter (both cable or infrared)
whenever available from the manufacturer.
This saves a lot of time if you shoot many (hundreds) photos as I do.

Regards
Paolo




Paolo G. ALBANO
Bologna, ITALY

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