The F10 actually has a 1/1.7" sensor which is a bit smaller than a 2/3"
sensor. DOF at f/7.1 and 14mm at the hyperfocal distance of 12-1/4 feet
should would be just over 6 feet to infinity. Since I guesstimate the
depth of the image at perhaps 50 feet, focus at 10 feet would have given
a DOF of 5-1/2 to 54. But, that's very little gain for taking a risk of
losing the longer side of the DOF if you should misjudge the point of
focus and focuse a bit too short. For example, if you actually focused
at 9 feet vs. 10 feet the DOF on the long side would drop from 54 feet
down to 34 feet. It's best to go for an approximation of the hyperfocal
distance and overestimate on the long side. If you can learn to judge
15 feet, for example, the short side would only increase from 6 feet to
6-3/4 feet and you'd be assured of infinity on the long end.
While I was on my long trip around the country it quickly became
apparent to me (and quite a surprise) that my most used lens was turning
out to be the Tamron 20-40 and almost always shot at either 20 or 40mm
and little in between. As soon as I realized that I fired up the laptop
and produced a little hyperfocal cheat sheet for 20 and 40mm that I kept
in my wallet. It says:
f/stop 8 11 16 22
====== == == == ==
20mm 6 4 3 2
40mm 20 15 10 8
Those are the rounded-up hyperfocal distances in easily guesstimated
even feet. Nearest focus, of course, is half of that. It worked very
well for getting landscape shots with good foreground focus. I did use
f/16 on occasion but f/11 is the limit to avoid diffraction on a 5D.
I haven't done any precise calculations but, for the small F10 sensor at
6MP I'd guess that you're already diffraction limited above f/4 and most
certainly by f/5.6.
Incidentally, your link to the modified photo didn't work.
Drs. D&D
Moose wrote:
>> and 984. 984 I really like, but would love to have it all in focus
>> front-to-back.
>>
>
> Hmmm.... Those last 11 images are from the F10. What I can't figure out
> is how they got to that size for the gallery. My usual work flow tracks
> aren't there and the color balance on 394 is obviously wonky. The rocks
> weren't purple.
>
> And you are right, it's pretty fuzzy. Shot at f7.1, 14 mm on a 2/3"
> sensor camera, it should have considerable DOF. Dr. D&D probably knows
> how much - and also that resolution is probably diffraction limited @ f7.1
>
> So I've posted a new version to the gallery. Not exactly tack sharp, but
> pretty much equal sharpness throughout. The overall slight lack of
> definition is probably partly diffraction limiting and partly the
> difficulty of rendering complex foliage at that size.
> <cid:part1.02070206.00060609@gmail.com>
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