Hold your pinky finger at arms length. compare it to the scene you want
to photograph, that is the smallest detail that will be resolved by your
135mm lens at f11, (I got that by looking at the stopped down diagram of
a 135mm from the front by the way, a usefull trick, sometimes). if
it's outside of the DOF for the focus point. The DOF for a 135mm lens
is pretty limited and focused at infinity the near limit is more than
100 yards away. I'm surprised you got anything that looked to be
remotely in focus. Another problem is that on the DS a 135mm lens is
~200mm on 35mm. I know that 1/200 is rule of thumb but really there is
going to be some camera movement, unless you're using the best possible
hand holding technique and face it in the excitement that's just not
going to happen.
So here's my advice. The DS has pretty clean output at ISO 800. If you
want to rely on DOF, then, under the conditions you described, you can
stop down to f22 and set your focus point at 40 feet. The lens opening
is about twice the size of a match head, so if your prints are small
enough a lot more will appear to be in focus, and everything between 30
and 50 feet away will be "sharp". However you'll still have camera
movement. You probably want to keep the shutter speeds above 1/400 so I
hate to say this but you'll probably have to open up to f11 and actually
change focus to follow the action. I know you've complained in the past
about having trouble manually focusing, but there's really no way around
it.
On 6/6/2011 8:40 AM, Eric Weir wrote:
I remain frustrated at my inability to get well-focused shots. Saturday I was
out exploring neighborhoods around the community in which I work and had my
camera along. I came across an adult pickup soccer game on one of the school
playing fields. I stopped and sat in the shade with a group guys who were
taking a break from the game. Then I went out of the field and shot about a 100
images.
I was looking forward to seeing the result. It was sunny mid-morning. The
camera's a *ist DS. The lens was an M 135/3.5. ISO was 200. Aperture was mostly
around f11. About half the images were shot at 1/250, half at 1/180. I kept
focus set at infinity.
I thought surely, at that speed, with that focus, at the distance at which I
was shooting I'd get a few sharp well-composed images. A handful -- less than
five -- are so-so, but not really sharp. The rest are all fuzzy.
Why can't I get a sharp image?
Thanks,
------------------------------------------------------------------------------------------
Eric Weir
Decatur, GA USA
eew...@bellsouth.net
--
Where's the Kaboom? There was supposed to be an Earth-shattering Kaboom!
--Marvin the Martian.
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