What are you guys shooting at? f/1.4 with a 10,000mm lens? For an example with
the 135mm f4.7 on the Graphic set to f/4.7 and infinity everything from 94 feet
to the Andromeda Galaxy is in focus (I use that lens because it is one I have
calculated). So if my focus is set anyplace between 94 feet and infinity, object
at infinity will be in focus. It is not like you don't have any depth of field
to work with when your subject is 235 thousand miles away. Even if your
hyperfocal distance is something like 10 thousand miles your DOF is far more
than enough to insure proper focus. That BTW is why autofocus is so problematic
at infinity. The system can not tell the difference between the hyperfocal
distance and actual infinity. Though as long as you are not blowing the photo up
beyond the value used to calculate the DOF infinity should still appear sharp.
Now if you are shooting something at 20 feet with a 600mm f/4.0 lens having your
infinity mark off a 1/4mm or so is going to affect scale focusing, but it will
not at infinity you just have too much slack to work with out there.
--
Herb Chong wrote:
the infinity mark isn't actually focused for an object at infinity except at
a specific temperature.
Herb....
----- Original Message -----
From: "Graywolf" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, October 28, 2004 1:31 PM
Subject: Re: Lunar Eclipse under way!
Ummmm..?
Surely the moon is at infinity. I can not even begin to see how you could
have a
focus problem. Autofocus problem yes, focus no.
--
graywolf
http://graywolfphoto.com/graywolf.html
