[Andy01 (Andy)]

Originally Posted by SimmoW

Nice Andy, Jen Bryent will love that purple!

Cheers Simmo - I must have been channelling Prince during processing

Originally Posted by RickS

Very cool, Andy

Thanks Rick

Originally Posted by Placidus

A mountain of amethyst!

There is an excellent hippopotamus lurking at bottom left.

Well done!

Cheers M&T - Yes, it has a remarkable crystalline appearance

Originally Posted by atalas

Excellent depth Andy and a fantastic object presented extremely well

Cheers Louie, thanks very much for the positive vibes.

Originally Posted by markas

Great result! A really unusual image.

Is there much N actually there? It seems to me that for image train f-ratios less than about f/4 you are getting lots of Ha in the N channel. I'd be interested to know how different the Ha and N subs are....

Whatever, a terrific image

Mark

Hey Mark, thanks for the nice compliments on the image.

As to your question, there was "just" enough difference between the Ha & N2 to map as seperate colours, and as the S2 signal was fairly weak I had to bin it x2.

From the Astrodon website - Ha emits at 656.3 nm and NII emits most strongly at 658.4 nm (and weakly at 653.8 nm). These are very close together spectrally.
Our 3 nm H-a begins to separate both emission lines and reduces the NII contribution significantly.
Our recent blueshift data show that Astrodon 3 and 5 nm filters can be used with nearly all systems as fast as f/3.5 with virtually no loss in emission signal, so you do not need to buy custom "upshifted" filters if you have both fast and slow systems.

Hydrogen-alpha 656.3 nm
Nitrogen NII 658.4 nm
Sulphur SII 671.6 nm

Originally Posted by multiweb

Very cool.

Cheers Marc, yes maybe even glacially cool

Originally Posted by Jeff

Great find ... an epic target indeed.

Not sure the name will stick though Andy.
I would prefer "Mystic Mountain" or maybe the "Cumulonimbus Nebula".

Well Jeff, when you go find your own patch of new/rarely imaged sky, you get to name it whatever you like!
My 9 y/o son named this one, so there it is! Mystic Mountain is kinda cool though

Originally Posted by strongmanmike

This is very interesting approach Andy and a lovely job, well done on using the lap top on Holidays too ...how did you get away from the W & K's

Oh and good on you for trying to show all three wavelengths too

As you know I am currently hammering this too and although there is heaps of Ha, I note as you have, there is essentially no OIII so the use of the NII was a good approach, how much of that is there? Given the lack of OIII (I don't have an NII filter) and not thinking an SIIHa version would work that well..? I think I have decided to do an LHaRGB version

My FOV shows the whole feature, and turned 90deg anticlockwise, it resembles the profile of the BFG

Mike

Hey Mike, thanks for the nice words!
As mentioned above the N2 signal is there and closely aligned to the Ha. As the S2 was so weak I had to bin it x2 so your idea of LHaRGB has great promise.
Unfortunately that's not an option from my suburban backyard, so I'll be very interested to see your results!

Originally Posted by Camelopardalis

Beauty Andy

Thanks very much Dunk!

Originally Posted by JA

Very mystical Andy. Great Image

Best
JA

Cheers JA - a new target for everyone to have a crack at now