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Richard Crisp
February 23rd 04, 12:41 AM
Check this out:

http://www.fairchildimaging.com/main/area_486.htm


or for sheer size:

http://www.fairchildimaging.com/main/area_595.htm

can you imagine a 3+ inches per side 81 megapixel sensor?

Zowie, that must be one expensive chip.

Dennis Persyk
February 23rd 04, 10:35 PM
I like my dinky little MX716 camera because it reads out all 361 K
pixels in about 5 seconds. The readout time on that Fairchild beast
is 5.6 minutes. Heck, you could almost develop a roll of film in that
time. Besides, what do you do with 15 micron pixels?

Clear skies,

Dennis Persyk
Igloo Observatory Home Page http://dpersyk.home.att.net
Hampshire, IL

"Richard Crisp" > wrote in message >...
> Check this out:
>
> http://www.fairchildimaging.com/main/area_486.htm
>
>
> or for sheer size:
>
> http://www.fairchildimaging.com/main/area_595.htm
>
> can you imagine a 3+ inches per side 81 megapixel sensor?
>
> Zowie, that must be one expensive chip.

Chris L Peterson
February 23rd 04, 10:48 PM
On 23 Feb 2004 14:35:52 -0800, (Dennis Persyk) wrote:

>I like my dinky little MX716 camera because it reads out all 361 K
>pixels in about 5 seconds. The readout time on that Fairchild beast
>is 5.6 minutes. Heck, you could almost develop a roll of film in that
>time. Besides, what do you do with 15 micron pixels?

Of course, if you integrate for a couple of hours, who cares if it takes five
minutes to get the data? And 15u pixels are about right for a 3m focal length
scope- that is, a typical 12" SCT. On the sort of scopes a sensor like this
would be used on, with corrected optics over more than three inches, 15u is
going to be way undersampled without adaptive optics.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Richard Crisp
February 24th 04, 01:26 AM
"Dennis Persyk" > wrote in message
m...
> I like my dinky little MX716 camera because it reads out all 361 K
> pixels in about 5 seconds. The readout time on that Fairchild beast
> is 5.6 minutes. Heck, you could almost develop a roll of film in that
> time. Besides, what do you do with 15 micron pixels?


I use 24x24 micron pixels in my Dream Machine camera (TK1024 sensor,
1024x1024, ~1" on a side) on my c14 at 4430mm focal length. I like the
results I get with it.

here are a few samples:

http://www.rdcrisp.darkhorizons.org/ngc2264_cone_nebula_ha_page.htm

http://www.rdcrisp.darkhorizons.org/m1_crab_nebula_ha_n2_page.htm

http://www.rdcrisp.darkhorizons.org/ngc6820_ha_close_page.htm

http://www.rdcrisp.darkhorizons.org/trapezium_sii_page.htm

http://www.rdcrisp.darkhorizons.org/m27_dumbbell_nebula_hao3b_page.htm

http://antwrp.gsfc.nasa.gov/apod/ap030908.html

etc

I think big pixels are great. They are really fast. With my C14 and my AO7
used with the beam splitter, the 24x24 micron pixels of the TK1024 work
fine.

matt
February 24th 04, 02:14 AM
"Richard Crisp" > wrote in message
...
> Check this out:
>
> http://www.fairchildimaging.com/main/area_486.htm
>
>
> or for sheer size:
>
> http://www.fairchildimaging.com/main/area_595.htm
>
> can you imagine a 3+ inches per side 81 megapixel sensor?
>
> Zowie, that must be one expensive chip.
>
>
>

the 81Mp is probably more of a compromise than the 16MP , due to the smaller
pixel size. Most very large professional cameras seem to use around 13-15um
pixel sizes, like the QUEST , OMEGA Prime etc .
As far as cost goes, I'd be surprised if a couple of 81MP chips cost more
than a whole mosaic of 115MP made up of 2MP chips .