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markas
01-05-2020, 03:46 PM
This one is a 3.4 hour RGB grab taken Monday night. The original image was cropped from 52' square to 22' x 20'. Processed in Pixinsight, finished in PS.


At the next opportunity, I will shoot a few hours of L, which I hope will drag out a bit more detail.


Monday night was fairly clean: seeing 1.8" - 2"; best SQM ~21.2. Almost no surface wind.

codemonkey
01-05-2020, 03:59 PM
Another lovely Cen A! Great job Mark. It's pretty ****ing amazing what everyone's pumping out these days.

Atmos
01-05-2020, 04:03 PM
Excellent rendition Mark, would love to see a higher res :thumbsup:

gregbradley
01-05-2020, 06:54 PM
That's superb and only 3.4 hours and no luminance? Wow, you really got a lot out of that imaging session.

What is the scope and camera?

Greg.

markas
01-05-2020, 10:52 PM
Lee, Colin and Greg,


Thanks for the comments. Much appreciated.


With the rotten weather we've been getting, I don't know when I'll get the needed Luminance frames......



Greg, the telescope is a custom 300mm RiDK f/8 unit from Officina Stellare, and the camera is a Moravian G4-9000. (The KAF 9000 has never been very popular, probably because of its RBI characteristics. However, it has a high QE for a CCD, 110,000e- full well, and 10e- RN. Pixels are 12micron)



The system resolution of 1"/px is a good match for the seeing I get at the Macedon site.



Mark

gregbradley
02-05-2020, 06:32 AM
Wow, that is a serious scope and camera combo. I nearly got a Proline 9000 once. Do you dither to get rid of RBI or use the IR flushing or nothing?

Greg.

topheart
02-05-2020, 09:29 AM
Well done Mark!
Nice scope!!
Cheers,
Tim

Paul Haese
02-05-2020, 11:41 AM
Very nice Mark. Great colour and detail.

markas
02-05-2020, 02:56 PM
Greg,
I use 15 px dither.

Preliminary setting up - PA (system is on a rollabout, not in an observatory), and AF - are done with the sensor uncooled.
If there are very strong stars in the vicinity of the target, I avoid meridian flips. If all else fails, (which almost never happens) there is always the context-aware healing brush in Photoshop as a last resort:)


Mark

markas
02-05-2020, 03:03 PM
Thanks, Tim. The scope performs very well, and seems to be very stable with change in temperature. Flexure in the image train must no doubt be present but I've not been able to detect it.

markas
02-05-2020, 03:04 PM
Thanks Paul. I appreciate your comments.
Mark

strongmanmike
14-05-2020, 01:25 AM
A solid and colourful Cen A Mark :thumbsup:

Mike

markas
17-05-2020, 10:25 PM
Thanks, Mike

Placidus
18-05-2020, 01:28 PM
That's astonishingly good for the time. The relativistic jet is very clear.

markas
19-05-2020, 11:03 AM
Thanks for the comment, M&T. The camera/OTA combination is a very fast acquirer of data - just have to manage the RBI!


Mark

PeterSEllis
22-05-2020, 09:27 AM
Hi Mark,
Nice clean sharp shot, a good one for your collection. Seeing 1.8" to 2", it doesn't get much better than that in Melbourne.

Peter

markas
22-05-2020, 09:49 AM
Thanks Peter. It was one of the better nights for seeing at my Macedon site, which is generally pretty dark (SQL typically 21.3 -21.6), but seeing is usually around 2.5".


Mark

marc4darkskies
22-05-2020, 10:05 AM
That's a really good image Mark! :thumbsup:

YAY for Officina Stellare! :D

markas
23-05-2020, 10:17 AM
Thanks Marc - certainly we agree on OS:thumbsup:


Mark