> "Pierre Bellavance" <[EMAIL PROTECTED]> wrote:
> I had figured that this would be useful if I want to make a picture
> of, let's say, a flower at 9.5 inches with a mountain in the
> background... extreme pictures... but will I want to focus often
> at 9.5 inches from the glass? Can I use a low power close-up lens
> on a 20-35 lens?
Hi Pierre,
At close focussing distances, DOF is quite shallow. For a 20mm lens
focussed to 25cm (9.8 inches), DOF for f/16 is from 0.20m (7.9 inches)
to 0.33 (13 inches).
So, if you focus your non-tilting 20mm lens at its closest focus, you
will NEVER get the flower AND the mountain in sharp focus!
If you want that mountain and the flower to be sharp, the hyperfocal
method suggests focussing the 20mm lens to one meter, and
putting camera 50cm from the flower.
Close focussing of one meter is within the capabilities of both the
20-35 zoom and the 20/2.8
Or you could get the Nikon "Fun" 20mm f/8 which has fixed focus at
its hyperfocal distance (2m), with a DOF from 1m to infinity.
Cheers
Julian Loke
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