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Old April 12th 07, 08:42 PM posted to alt.binaries.pictures.astro
Rick Johnson[_2_]
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Posts: 3,085
Default ASTRO: Cocoon Galaxy NGC 4490 and NGC 4485

Thanks. The images looked like those from a Sony chip but the ones
Starlight Xpress uses in that 752x580 range are a bit over 8 micron in
size. That didn't seem to match your image scale. Now it makes sense.
Nice deep wells help a lot and good response curve is nice when moving
into color. It should work pretty well for longer exposures.

When I started with the 6" f/4 a couple weeks short of a year ago now.
I could go 5 minutes without guiding. At F/4 that's plenty long! It
goes deeper for galaxies than the 14" does using 10 minute sub frames
binned 2x2 (equivalent to f/5). The longer focal length gives a lot
more detail however. Seems no matter what you do in life it's all a
compromise!

Rick


D van den H wrote:

Rick,
This is the spec of the CCD chip:
CCD type: Sony ICX083AL SuperHAD CCD with ultra low dark current and
vertical anti-blooming.
CCD pixel data: Pixel size: 11.6 x 11.2uM, image format 752 x 580 pixels
(High Res. mode), or 23.2 x 22.4uM.
CCD size: Imaging area: 8.7mm (horizontal) x 6.5mm (vertical).
Spectral response: Peak response at 520nM (Green), 50% at 400nM (Violet) and
670nM (Near infra-red).
Quantum efficiency: Approx. 65% peak at 520nM.
Readout noise: Less than15 electrons RMS.
Full-well capacity: Greater than 300,000 e-.
Anti-blooming: Overload margin greater than 800x
Dark current: Dark frame saturation time greater than 100 hours. Less than
0.1 electrons/ second at +10C ambient.
Data format: Full 16 bits.

So far i enjoy using this chip, Originally they come from a Sony broadcast
camera where they are mounted on a optical block one for each color (3 in a
block).
I have a couple of these block here... perhaps build a super CCD head for
the three colors..

reg
Dirk

"Rick Johnson" wrote in message
...


D van den H wrote:


Did not see my posting, so here's another try..
Seeing was not to bad last night, transparicy still not so good..
36 x 90 sec.
Dark corrected.
10"SCT
Homebuild CCD camera.
Some MAXIMDL
CS2
Strange looking galaxy, a bit of a mess..
Thx for looking
Dirk

------------------------------------------------------------------------


Both made it to my server. Usenet amazes me sometimes. A post won't hit
your own server but show up on the other side of the world just fine.

That's another one on my to-do list. Looks like yet another clear night
and a third night of a dead computer power supply. They have one coming
at least. I can't even process as all my images are on that computer and
now the supply is totally deceased.

What chip do you have in your camera?

Rick
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