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Mallincam in CCD mode

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#1 A. Viegas

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Posted 20 October 2013 - 07:59 AM

A few nights ago, Chris (Astrogate on NSN) put on an excellent show using his MCX2 and trying out the CCD mode in the Mallincam. This mode is basically just AGC at zero, or no gain and produces much nicer stars. Anyhow I managed to roll out of bed this morning at 4am to do a few tests and captured a few quick shots of M42 here using my C8. These were done at F8 so just over 1600mm FL and I was not guiding. There was no filter (and it was a full moon!) and I did not have dark frame subtraction or hot pixel removing or anything. Matter of fact I was testing a new laptop so basically had nothing at all tweaked in Miloslick, not even the histogram (yeah i am lazy, or just still sleepy)

Anyhow, thought I'd post. Next week I will try and get some fainter DSOs in CCD mode, but will have to guide and stack probably to make them look as pretty as M42 with zero tweaking!

Al

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#2 GlennLeDrew

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Posted 20 October 2013 - 09:45 AM

I do believe that CCD mode also has APC (advanced pixel control, or sharpening) disabled. (APC, at least when set to more than minimal, introduces black 'halos' around stars.)

#3 Jack Huerkamp

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Posted 20 October 2013 - 04:31 PM

That is true for elevated settings of the H and V APC values as the higher the APC is set, the higher the amount of digital signal processing done inside the camera. In addition to enhancement of details in nebulae and galaxies, elevated APC can produce halos around bright stars. Its a trade-off. Do you want to have the increased detail in the target with commensurate halos around bright stars or forgor the increased detail to keep the star images clean.

At Chiefland Astronomy Village one night I was observing with a friend with his MallinCam and 28" f/3.7 DOB. We were looking at M82 and started with APC values set to minimum. We gradually increased the APC values up to maximum and were amazed at the increase in detail in the core of M82. Later that same night, we wentto M16 and re-ran the test. Due to the bright stars around the Eagle, we did see the halos. But the nebula also showed increased detail.

Jack Huerkamp

#4 Dwight J

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Posted 20 October 2013 - 04:36 PM

APC is still active in CCD mode. Setting it to H 0 and V 1 rounds up the stars and does not add black circles around stars at that setting. It just squares up the pixels.

#5 Chris A

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Posted 25 October 2013 - 02:14 PM

Very nice results Al and thank you very much for the kind words and most importantly bringing this topic up.

Clear skies,

Chris A
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