Cas A RGB at F10

[physicus]

As supernova remnants go, the Crab Nebula seems to get all the attention.  So here for a change is Cassiopeia A.  Unfortunately, while it may be the brightest radio source in the sky outside the solar system, there's precious little in the visible.  And it's small too.  This is about 3 to 4 hours worth of RGB in 300s subs, with the C9.25 at f10 / AZEQ6/ Celestron OAG w ZWO ASI120MM / Atik 460 binned 2x2.   I hardly ever use the scope at f10, but it was set up and calibrated for a crack at Einstein's Cross (clearly feeling optimistic these days), but the seeing wasn't up to that.   The Hubble version of Cas A looks like a Christmas ornament of course, and while I haven't got the same sparkle, there is a bit of structure visible.  I got a couple of hours of Luminance on an earlier occasion, but it's low quality and only damages the image - so RGB it is.

Tim

 

[Lars]

Congratulations to that catch!

I didn't even think it was possible to image this without a 20" and 20h (that's what Ken Crawford used for his image). And like you I have been feeling optimistic about Einstein's cross but one would probably need exceptional seeing to crack that one.

/Lars

 

[Chris]

Fabulous image! I can't recall seeing this imaged on SGL, probably because it's so tricky. Congratulations!

[Chris]

Edit: double post

[toxic]

great image indeed its a faint so and so 

[sloz1664]

You are a brave man, but then again if you're not brave you don't get fabulous images like this. 

Steve

[cfpendock]

You always seem to go for the interesting stuff, Tim.  This is an amazing image, considering the object is incredibly faint and only about 5 minutes across, but it shows a lot of the structure.  That is a benefit of imaging at long focal length, despite the difficulties.  Will you add luminance given the chance of some clear shy?  It might be my screen, but is there a slight purple tinge to the overall image (possibly necessary to show the structure).

Can you image x-rays through cloud?

Chris

[ollypenrice]

Bravo! This is a cracking catch and new to me in visual, though I've read about it as a visual source. What a tremendous post.

Olly

[physicus]

1 hour ago, cfpendock said:

You always seem to go for the interesting stuff, Tim.  This is an amazing image, considering the object is incredibly faint and only about 5 minutes across, but it shows a lot of the structure.  That is a benefit of imaging at long focal length, despite the difficulties.  Will you add luminance given the chance of some clear shy?  It might be my screen, but is there a slight purple tinge to the overall image (possibly necessary to show the structure).

Can you image x-rays through cloud?

Chris

Thanks Chris.  Waiting for a bit of transparency to get the luminance.  I have a couple of hours, but it's poor.  Re the purple tinge - quite likely!  I rushed this to press without agonizing over the processing for a few hours like I normally do.  A long calm re-process may well balance things up and bring out more detail and colour differences.  While the rig is set up like this I think I will try for more data, skies allowing.  My green was noisy as hell (even more than usual), so that channel was well softened/noised.  Surprisingly little processing otherwise - all Nebulosity + PS.  

Btw, apologies for not catching up.  Will be in touch.  Cheers Tim.