misunderstanding concerning CCDs

There's something I think I have wrong concerning CCDs and I wanted to find
out the correct answers. Say I have a webcam, which has an ICX098 CCD and
another camera with an ICX424 CCD. I want to image Jupiter with a C8 and
3x barlow ahead of the webcam and other camera. When the webcam/ barlow/ C8
combo are used, let's say that the diameter of Jupiter on the laptop screen
is 3" across. Now, I remove the webcam and replace with the camera with the
ICX424 CCD, making sure the CCD is the same distance as the webcam's. What
will the image size be on the screen now?

The part I'm finding confusing is this: since the ICX424 covers a larger
pixel area than the 098 and also has a larger pixel size(?), I am assuming
the amplified Jupiter will not be the same size on the screen that the
laptop produces. Am I wrong? Or is it that the 424 just covers a wider
area and the image size of Jupiter is still the same?

Finally, what benefit, if any, would there be with this combo system if
using just the 424? Would there be better resolution than the 098 offers or
worse?

I know, lots of questions here, but would like to end my confusion once and
for all!

Thanks,
John Edmund

Hi John,

laptop produces. Am I wrong? Or is it that the 424 just covers a wider
area and the image size of Jupiter is still the same?

Assuming you ar looking at images from both at 100%, more pixels will just
give a wider area on screen. Larger pixels will result in the image being
smaller as the size of pixels on the screen is constant. But larger pixels
means the object will cover less pixels, resulting in a smaller image
onscreen.

Regards

Eddie T.
http://astroshed.com

"John Edmund" wrote in message
link.net...
There's something I think I have wrong concerning CCDs and I wanted to
find
out the correct answers. Say I have a webcam, which has an ICX098 CCD and
another camera with an ICX424 CCD. I want to image Jupiter with a C8 and
3x barlow ahead of the webcam and other camera. When the webcam/ barlow/
C8
combo are used, let's say that the diameter of Jupiter on the laptop
screen
is 3" across. Now, I remove the webcam and replace with the camera with
the
ICX424 CCD, making sure the CCD is the same distance as the webcam's.
What
will the image size be on the screen now?

The part I'm finding confusing is this: since the ICX424 covers a larger
pixel area than the 098 and also has a larger pixel size(?), I am assuming
the amplified Jupiter will not be the same size on the screen that the
laptop produces. Am I wrong? Or is it that the 424 just covers a wider
area and the image size of Jupiter is still the same?

Finally, what benefit, if any, would there be with this combo system if
using just the 424? Would there be better resolution than the 098 offers
or
worse?

I know, lots of questions here, but would like to end my confusion once
and
for all!

Thanks,
John Edmund