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avandonk
05-04-2016, 09:03 AM
Exposures 15x5 min for each of RGB.

Large image here 13MB. FoV 3x3 degrees.

http://d1355990.i49.quadrahosting.com.au/2016_01/OC_rgbc.jpg


Bert

AG Hybrid
05-04-2016, 09:56 AM
Nice. Bright little galaxy there towards the bottom left. Wonder what its LMag is?

RickS
05-04-2016, 10:16 AM
Bert,

The star shapes in the corners are still a long way from perfect (see attached pic generated with the PI AberrationInspector script.) Have you given up on your contraption for removing tilt?

Cheers,
Rick.

Atmos
05-04-2016, 10:44 AM
I think the problem is that the telescope is designed for a camera closer to the KAF-8300 than the 16803 :P

RickS
05-04-2016, 10:54 AM
The spec for the scope says "Full corrected and illuminated field: 42 mm (24x36 mm full format)" but I believe that Bert had some discussions with his supplier about using the larger sensor.

Cheers,
Rick.

strongmanmike
05-04-2016, 11:01 AM
Always like a shot of Omega that shows the Galactic Cirrus :thumbsup:

Mike

IanP
05-04-2016, 03:17 PM
Aberration or not, it is still a great shot :thumbsup:

Slawomir
05-04-2016, 09:03 PM
Nice colours Bert, with rounder stars would have been a great photo :thumbsup:

Ross G
05-04-2016, 09:32 PM
Great looking photo Bert.

Nice colours and amazing detail.

Good to see your photos back on IIS.


Ross.

Atmos
05-04-2016, 09:52 PM
That's what I meant, it is not corrected for a 36.8x36.8mm sensor :P As long as one does not mind the less than perfect stars in the corners, the setup works really well.

Now that I have actually had a chance to look at the full res on my laptop and not just the 200kb version on my iPhone... It really is a great shot :) So much going on, I don't remember ever seeing the field so rich with stars!

dylan_odonnell
05-04-2016, 10:30 PM
I think this is great, and huge! At such high resolution when viewed on screen or in print the minor aberrations are practically benign.

avandonk
06-04-2016, 07:39 AM
Yes maintaining perfect alignment with a critical focus zone of less than 20 micron is a pain. In fact any flexure will ruin the best alignment.

I have stabilised the optic train to the point where I have about one pixel per hour in X and two pixels per hour in Y flexure.

The OC image does need a bit of further alignment. I am doing this when I get a clear night. I need to move the camera about 100 micron to the right errr or is that left?

The temptation always is to collect data not fiddle with the parameters.

Here is an animated gif of my RH200 image against an Astro Physics 155mm @ F5.5 note same camera


http://d1355990.i49.quadrahosting.com.au/2016_01/OCcomp.gif (http://d1355990.i49.quadrahosting.com.au/2016_01/OCcomp.gif)


The Astro Physics image is here

http://tvdavisastropics.com/astroimages-1_000074.htm (http://tvdavisastropics.com/astroimages-1_000074.htm)



My aim is to make large mosaics so what happens at the corners is irrelevant as any aberrations disappear with averaging overlap and or trimming.

Have a look at the six panel mosaic of the LMC here in Deep Space


Bert

multiweb
06-04-2016, 08:04 AM
Pretty deep Bert! Good to see the RH playing outside again. :thumbsup:

janoskiss
06-04-2016, 12:14 PM
Geez, you're a fussy lot. :lol: I would not have picked a fault with the image. It's mostly only the top left corner though that looks NQR at full size. (I'm reluctant to post my pathetic Omega Cent shot now. I guess in the beginners' AP forum I'll get away with it. :P)

Amazing shot anyway, Bert! :thumbsup:

@AG Where is that galaxy? I cannot find it.

RickS
06-04-2016, 01:35 PM
I'm normally not that fussy about images either, apart from my own, but Bert has gone to extreme lengths to remove flexure and previously claimed success, so it's not unreasonable to test his assertions.

Cheers,
Rick.

janoskiss
06-04-2016, 04:36 PM
Fair enough. Just call me Donny and tell me to shut uhmm up...

DavidTrap
06-04-2016, 08:13 PM
It's certainly an impressive starfield Bert - OC almost merges into the background.

I just wonder whether you've got some reflections - I've highlighted them on a low res image. I looked at your image on a couple of monitors and could see it on both. Thoughts?? :shrug:

DT

avandonk
08-04-2016, 08:39 AM
Here is another version showing the core of OC a bit better. 7MB

http://d1355990.i49.quadrahosting.com.au/2016_01/OCcore.jpg


Bert