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Captured by
Lawrence Parchman

Sculptor Galaxy (NGC 253)

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Posts Made By: dan kowall

January 28, 2008 04:27 PM Forum: CCD Imaging and Processing/Deep Sky

LDN 1622 & Barnard's Loop in Ha

Posted By dan kowall
Dean Rowe said:
......I did take another 10 hours of data that I didn't use because the moon was too close. I learned that shooting long Ha exposures with the E180 isn't pretty if moonlight gets in.......
Nicely done, Dean.
Even the large size looks good. You made the right choice in going for the extra exposures to reduce the noise.
I'm surprised that the moonlight affected some of your subs, I've imaged about 15 degrees away from the moon with the 6nm without obvious interference.

dan

February 4, 2008 04:19 PM Forum: CCD Imaging and Processing/Deep Sky

Sharpless 297

Posted By dan kowall
This one is new to me, too, Jim, but it looks like you've integrated the color nicely.

dan

February 4, 2008 04:25 PM Forum: CCD Imaging and Processing/Deep Sky

NGC 1514 - the crystal ball nebula

Posted By dan kowall
dietmar hager said:
....I imaged this tough little planetary nebula ......
I've been wrestling with a version of this nebula, too. It is a tough little bugger.
You've done well, Diets. The large version shows good color and detail.

dan

February 8, 2008 03:16 PM Forum: CCD Imaging and Processing/Deep Sky

Processing question: HELP!!!!

Posted By dan kowall
Luca,
You didn't say what processing program that you are using, so I can't give specific advice, but here are some guidelines:
-----Your averaging method that you described will only work well if the total of each group of subexposures is equal, otherwise some groups will have a greater contribution they should and some will have lesser contributions.
-----If you intend to use combined images to create a master combine, then each of those sub-combines should be sums (preferably into 32-bit).
----Here is a good procedure:
***Process each group of exposures this way: by normalizing, doing data rejection, and finally doing a sum combine.
***Combine the processed subexposure sums with a simple mean (if the groups are equal) or a sum combine. You don't want to do normalization or data rejection for this combine.

I hope this helps,

dan

February 8, 2008 07:00 PM Forum: CCD Imaging and Processing/Deep Sky

NGC 2371 L-OSC

Posted By dan kowall
What an interesting planetary, Diets.
I wasn't familiar with it, but it's on my to-do list now.

dan

February 11, 2008 11:48 PM Forum: CCD Imaging and Processing/Deep Sky

A Late Andromeda

Posted By dan kowall
Thanks for the comments, gentlemen.

dan

February 13, 2008 10:15 PM Forum: CCD Imaging and Processing/Solar System

Saturn 12th Feb from murrumbateman

Posted By dan kowall
That is stunning, Anthony.
Well done.

dan kowall

February 17, 2008 05:25 PM Forum: CCD Imaging and Processing/Deep Sky

Sharpless 280

Posted By dan kowall
C8 at f/3.6
I guess that you gave it the gas to get it up to that speed, Jim.
It certainly is an appropriate field of view for this off-the-beaten-path nebula.
Good looking color in this image.

dan

February 24, 2008 10:09 PM Forum: Equipment Talk

Gemini - User coordinates

Posted By dan kowall
Show Information--->RA/DEC Coordinates--->Enter RA/DEC
then do a GoTo.

dan kowall

March 12, 2008 03:42 PM Forum: CCD Imaging and Processing/Deep Sky

Simple M81-82

Posted By dan kowall
Thomas Davis said:
..... Even though it's only 2 hours total it does show some of the integrated flux nebulosity in the region. If I bring up the background the integrated flux really comes out ........
It wasn't that long ago that we processed the flux out as a gradient.
I'm glad to see that your weather is improving somewhat, Tom.
My regards,

dan

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