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CoolhandJo
16-11-2011, 03:36 PM
Here is my very first image from my new Atik 4000.

Finally got out and tested the Camera. 3/4 moon and a bit misty. Target the Sculptor Galaxy.

Here are two images. First is a stack of 4 x 10 min L, fully calibrated with darks, bias, flats, flat darks.

Second a crop of the Sculptor

Camera runing at -15 deg temp.

Image scale 3.18 arsec/pix through ED80 on EQ6 phd guiding - Imaged size reduced to 50% for uploading

Separate thread on this can be found here

http://www.iceinspace.com.au/forum/showthread.php?t=75459

Feedback sought

atalas
16-11-2011, 08:49 PM
Congrats on first light Paul! nice work on the galaxy....stars look a bit harsh,maybe a touch clipped.

Paul on the cooling,couldn't the camera do better than -15?why set so low?

CoolhandJo
16-11-2011, 10:13 PM
Yes, the flats were not right. I need to tweak the flats for sure as they did clip the stars.
Cooling on this camera is 40Deg below ambient. The night I took this it was about 25 deg c, so I set the temp point to -15DegC. There is optional water cooling which gets its down further though but I am yet to install it.

atalas
17-11-2011, 09:21 AM
Don't know why the flats would clip the stars Paul? looks to me like they haven't been protected enough while sharpening or,the sub exposures were slightly too long for the luminance....did you have a reducer on the ED80? at the native f/7.5 I would think you could go to 10 minute subs with the dynamic range of the Kodak 04020 chip.

The water cooling will be worth looking into for those worm summer nights when you need the cooling the most.

CoolhandJo
17-11-2011, 10:16 AM
Louie

yes, since posting my last reply I investigated and noticdd that the flats only moved the histogram ever so slightly so no clipping. Then I checked the raw fits and yes, you nailed it - it was sharpening that did it. I am not used to the Arcmin/pix and sharpening routine yet for this chip.

I have a reducer so it was imaging at f6. the raw fits suggest that the 10 min subs are still ok - so my bet its the sharpening.

I intend to add some RGB so I will make sure I do not use unprotected sharpening and or noise control on them

Re the cooling - yes I agree - but first I want to see if -15 deg + calibration is good enough.

Thanks for confirming in my mind that the flats are OK

atalas
17-11-2011, 12:10 PM
Hey Paul,I thought I remembered reading somewhere that the Atik 4000 had two stage peltier cooling so I looked this up.

http://www.optcorp.com/product.aspx?pid=319-320-1694-1695-15106&tb=2

Is there something different about your model?

strongmanmike
17-11-2011, 12:22 PM
Great start with the new camera Paul :thumbsup:..all fun from here

Mike

CoolhandJo
17-11-2011, 12:31 PM
Yes. I have that model. It has 2 stage peltier cooling but from what I know and have read it can only reach 40 deg below ambient. The single stage only reaches 20 deg below. Further cooling from there requires water assist.

Therefore if it's 25 deg c outdoors then two stage can get to - 15 deg sensor temp

CoolhandJo
17-11-2011, 12:33 PM
Thanks Mike! Really eager to get some rgb to add to this now!

Leonardo70
18-11-2011, 01:57 AM
Great first light....very nice details.
This is a great CCD .. ;)

Leo

multiweb
20-11-2011, 09:41 AM
Awesome shot Paul. Perfect guiding and a wealth of details in that lum. Great stuff. :thumbsup:

CoolhandJo
20-11-2011, 09:47 AM
I got to add some RGB to the image.

I still have to get my flats sorted out but on the whole I am happy with the camera and filters.

Final image LRGB 40:30:30:30
-15 deg, no sharpening applied, fully calibrated.

CoolhandJo
20-11-2011, 05:10 PM
Thanks Marc! Cant wait to get it on M42!

CoolhandJo
20-11-2011, 10:36 PM
For those interested here is a link to the full semi-uncropped version! I managed to sort out flats a bit better

http://i594.photobucket.com/albums/tt21/coolhandjo/Sculptor-final-NR2.jpg

Ross G
21-11-2011, 08:00 PM
Great shot paul.

So much detail.

The new camera is looking good.

Ross.