RE: [APML] D60/D100 was (new image: IC1396-Provia and halpha CCD)

["Koebel, Alen" <Alen.Koebel@christiedigital.com>]

Roland Christen wrote:

> You will not be able to resolve nearly as well using 
> a tri-color chip versus a monochrome chip. The fact 
> that you can capture color in one shot is a convenience

Indeed, I have seen few images taken with one-shot color 
astronomical CCD cameras (so far, only from Starlight 
Express - unless Apogee managed to sneak some one-shot 
LISAA's out) that look as impressive as tricolor or 
LRGB images taken with filter wheels. Of course, one is 
not always comparing apples-to-apples because of pixel 
size and focal length differences. But, in general, I 
think what Roland is saying is true. However, for CMY 
cameras (Starlight) the resolution loss isn't quite as 
bad as you'd think, because all of the pixels contribute 
to the luminance component of the image. The derived 
color components of the image do have much less 
resolution, but as we know from video practice and from
images like the one that started this thread, you can 
usually get away with that. So, I think a cooled two- 
or three-megapixel CMY-type, one-shot color CCD camera 
with 6, 7 or even 8 micron pixels would satisfy a good 
many astroimagers. But there ain't no such beast, today.


--  APML Archives at <http://astro.umsystem.edu/apml/>  ---
             Unsubscribe at <majordomo@seds.org>