wwp@yahoogroups.com:
Re: Sigma 8mm / Hyperfocal
Landis 2004-Nov-24 14:32:00
>I?m not Sam, but I think I can help. Hyperfocal approach means simply
>that when you focus on the infinity you waste a very big amount of area
>in focus, principally with a 8mm lens. For instance, if you place the
>focus ring at, say, 1 meter, and the aperture at f8, you?ll very likely
>(I don?t have the lens, so I?m estimating) have focus since about 30cm
>to infinity. You must look at those small marks on either side of the
>central focus index to be sure. On my 14mm, if I put the focus ring on 1
>meter, I get focus from 50cm to infinity at f8. The ideal is to put the
>infinity mark of the focus ring at the f number you?ll use, and then you
>can see the depth of field of the lens.
>HTH,
>Rodolpho Pajuaba
Those were shot at f/11 (supposedly the sharpest
f-stop for the lens), with focus being just shy
of infinity.
I have tried the hyperfocal method previously and
gotten blurry images. I've tried halving that
(ie shooting at f/16 and setting infinity at f/8)
and I still get blurriness in the distance. I
don't have any problems with this approach with
the Nikkor 10.5 FE, so I chalked this up to just
being the way of the Sigma 8.
I'm sure I'll continue to play with the Sigma 8
and use it in places for handhelds (like the
parade), but I'm really happy with 6 shots around
on the Nikkor 10.5.
-Landis