M33

[NigeB]

Evening All,

I've been sitting on a set of M33 subs I took last October - finally got around to doing something with them. It's been a bit of a challenge, difficult to do a reasonable background subtraction when there's so much going on, and I've found colour calibration a bit of a problem. This is as close to "natural" as I've managed so far. I took some H-alpha frames, but haven't added them in yet.

Exposure details: 

TOA-150 @ F/11 / Mesu 200 / Atix 460ex

10 minute sub-exposures
L:R:G:B  47:15:15:14 

Nigel

 

 

[kirkster501]

Excellent.  Lovely detail.  I think there is more still in there.

[Shibby]

Brilliant - so much excellent structure to admire!

[ollypenrice]

Great result.

To my eye the greens are a bit high, maybe?

Olly

[x6gas]

In my view that's a wonderful result.  I found M33 to be a difficult target to process as it is quite diffuse; you've brought out the Ha regions very well considering there is no specific Ha data in here.

I take Olly's point - though my attempt at this came out with similar colours.  I took the liberty of running this through HLVG and personally quite liked the result so it might be worth trying that...

[NigeB]

Hello Everyone,

Thanks for your positive comments! Kirkster, yes, I agree, I think there's more in there. I decided to back of a little bit - a lot of my images have suffered from processing noise, so I'm adopting a more cautious approach. But @wimvb provided some nice approaches to correcting this which I'm going to try.

Olly, I agree, it's definitely green-heavy. I've tried a little SCNR noise reduction and some manual adjustments, but I've so far succeeded only in making the colours look even less natural... One of the reasons I've held off adding in the H-alpha is that I found it exacerbated the issue (I've read that taking OIII and adding that into the Green channel can help that). 

I'll have a go at re-processing to see if I can improve things.

Thanks

Nigel

 

[Astrobug]

Nice shot. M33 is in delicate to process. The borders of the galaxy are tricky.