Re: Eyes vs Digicam in SCT Imaging

On Apr 22, 4:26 pm, Eugene <eugenhug...@xxxxxxxxx> wrote:
On Apr 22, 8:07 am, Chris L Peterson <c...@xxxxxxxxxxxxxxxxxx> wrote:

On Tue, 21 Apr 2009 16:56:11 -0700 (PDT), Eugene <eugenhug...@xxxxxxxxx>
wrote:

Then how come the Canon 400D can't work well with the
8" SCT functioning like a 2000mm telephoto lens?

I don't know what problem you're having. I use a 300D on my 12" SCT
(3000mm FL) and it works fine, just like any telephoto. People use DSLRs
on SCTs all the time with good results.

If you enable electronic confirmation with some kind of
adapter. You'll find out that it can't focus because of
lack of light. Contrast focusing method also doesn't
work well. My questions is how come our eyes see
the image very good with good contrast at 40-80X
yet the digicam can't automatically focus lock at it.
Also try to take picture with your 300D and 3000fl
SCT at shades in the trees. You can see that
it has difficulty focusing automatically (that is, you
don't use manual focus). It's like there is not
enough light or contrast reach the camera for
electronic focusing to work, something our eyes
can easily do. There seems to be some limits in
these machines. What is it exactly....

E

Let me elaborate. Your experience is mostly with
exposure that last minutes or hours. But in
terrestrial photography with your 300D and 3000mm
FL SCT, the shutter doesn't close fast enough at
f/10 for live action shot or wildlife where monkeys
jump in trees. So the limit seems to be in the
shuttering speed. Now with our eyes. When
we close our eyes and blink and open it. We
don't have to wait for seconds for the light to
fill our rods. We immediately see light.. .something
the digicam can't do as it takes some seconds
for light to fill up the ccd pixel. So what is that
the ccds can't do that human eyes can.. and
why can't ccds be made to function like eyes
where it can immediately close shutter and
watch action even at dim light...

E





Keep in mind that you're at f/10. When you're imaging something bright,
as in a daytime scene, that determines your exposure.

Equivalent magnification is 40X.

Throw out that idea. There is no such thing as equivalent magnification..

Brightness and
contrast is dim and poor when imaging say garden
at daytime. How do you make the pictures as good
as when simply looking at the eyepiece at 40X-80X?

Brightness is poor through the viewfinder because you aren't getting
much light. The image produced by the camera should look just fine.
_________________________________________________

Chris L Peterson
Cloudbait Observatoryhttp://www.cloudbait.com- Hide quoted text -

- Show quoted text -

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