Integrated Flux Nebula of MW2

[ampleamp]

Mandel Wilson 2 is just a part of a much wider region of Integrated Flux Nebulae in northern skies and as another challenge/test to myself i decided to see if i could see any never mind get even come close to the lovely image @Barry-Wilson produced nearly a couple of years ago,

except mine was taken between two towns in Shropshire 😉 

I could really do with some help/advice on the granular nature of some this (and some others) image. It was imaged at 1.67"/p with a Tak100DF and an Atik16200 assisted by an FSQ85/QSI683 yet to my eye it appears granular and I cannot yet work out what process I am over or under-doing. As with all the recent weeks, clear skies have been at a premium and those that are have carried haze or high cloud. There are 125 x 300" L, and 30 x 180" each of RGB.

Thanks for looking and especially anyone who can offer suggestions.

[MartinFransson]

That´s deep! Looks great, although I would (no I wouldn´t, but it might be a good idea ) back off on the stretching just a tad. I get the same type of granular noise when overstretching my data. There is just not enough signal to be pushed that hard. With even less data I tend to also get some larger, blotchy noise patterns.

[ampleamp]

Thanks Martin; i will be going back to see if i can make anything better of this but didn't want to keep doing the same thing over and get no improvement. Trouble is that there is literally nothing visible, certainly on individual subs and pushing the data is everything here; or just loads more data from a better quality sky??? 

[MartinFransson]

1 hour ago, ampleamp said:

Thanks Martin; i will be going back to see if i can make anything better of this but didn't want to keep doing the same thing over and get no improvement. Trouble is that there is literally nothing visible, certainly on individual subs and pushing the data is everything here; or just loads more data from a better quality sky??? 

Dark sky is everything on a target like this I´m afraid. That and loads of data

[tomato]

That’s a fantastic result given it was captured from (semi-rural?) Shropshire. 

Have you ever considered Imaging from the the Long Mynd? It is something myself and @Tomatobro plan to try at some point, if we ever get a fully clear and moonless night in Shropshire.

We had a few sessions in the 1980’s, it was quite a decent location back then, if you could get out of the wind. It will be interesting to see how good it is now.

[ampleamp]

Thank you. The Long Mynd is very dark and it would be great to have those skies at home though living next door to an army camp does have its advantages. Maybe not dark enough for this type of target however. Like you I have a multi scope rig so that isn’t being dismantled anytime soon but it would be a really good exercise to compare home with LM. Maybe i will give it a go as you have me thinking (and that’s never good!😁). 

[tomato]

Fortunately we have a 102mm APO and a EQ6 at our disposal for a travel rig, just need availability and the weather to co-operate.

I’ll post a report when we finally get up there...

[MartinB]

This is a wonderful image, so much to see in there quite apart from the IF.  I suspect you are starting to hit the buffers of analogue to digital to analogue conversion, quantisation error and all that stuff.  Basically there is always a limit as to how far you can go even with pristine data

[ampleamp]

Thank Martin, I will look into the limits as maybe I am being a tad too ambitious. 

[ollypenrice]

I think it's great. You have that brown IFN colour, too, which is good going. I reckon a little noise is allowed in IFN images!

Olly

 

[gorann]

I like it a lot! Quite an effort and a striking image.

Maybe, as Martin says, you could stretch it a little bit less. I also noted that you appear to have had some guiding problem making especially the smaller stars to appear as lines rather than round. I hope you do not mind that I downloaded your image and used the usual treatment for this in PS: making a copy layer of the image and then blend this with the original in darken mode, moving the top image using the move tool. That made the stars smaller and roundish and thereby supressed the apparent brightness of the star field, which made the IFN stand out more. I post a blow up of this before and after the star fix. Then I suppressed the stretch a bit with curves, and finally added a bit of noise (apparent in the blow up) since your image almost seemed too smoth (a bit to much NR?). This may have helped making it a bit more dusty (not sure about that though).

Cheers, Göran

Edited February 10, 2020 by gorann

[ampleamp]

Thanks Olly. 
 

@gorann thank you very much. That is quite an improvement. 👍🏼 Hands up re the stars. I hadn’t correct a mechanical issue - pretty sure it was a slightly shifted PA problem - and have now stripped down my widefield kit ready for being moved into the new obs but that’s another story. I am intrigued by what you did there and didn’t know that such an improvement could be made. You are right in that the whole star field loses its intensity and calms the image down. Not knowing anything about PS, this is far from standard to me but will find a tutorial somewhere.  

[ollypenrice]

12 minutes ago, ampleamp said:

Thanks Olly. 
 

@gorann thank you very much. That is quite an improvement. 👍🏼 Hands up re the stars. I hadn’t correct a mechanical issue - pretty sure it was a slightly shifted PA problem - and have now stripped down my widefield kit ready for being moved into the new obs but that’s another story. I am intrigued by what you did there and didn’t know that such an improvement could be made. You are right in that the whole star field loses its intensity and calms the image down. Not knowing anything about PS, this is far from standard to me but will find a tutorial somewhere.  

It's not a difficult one to do but you can make it easier to perform by first rotating the image so that the trailing is vertical or horizontal. That way you only have to operate the move function in one direction. 

Copy layer.

Blend mode darken.

Filter-Other-Offset. Make the offset a point too much rather than too little then you can go to Edit-Fade -Fade Offset and get micro control over the amount of offset.

Flatten and de-rotate.

Olly

[gorann]

Another way to get micro control of the movement that I sometimes use it to upscale the image size first, e.g. 4 times (if your computer can take it). In PS you do it under Image->Image size. After you have done the move you can scale it back to the original size.

[wimvb]

On 04/02/2020 at 16:05, ampleamp said:

Thanks for looking and especially anyone who can offer suggestions.

Excellent image. 

What processing software do you use? There are a few good tutorials on processing this kind of images using Pixinsight. 

http://www.deepskycolors.com/archivo/2010/05/07/multi-scale-Processing--Revealing-very.html

http://www.deepskycolors.com/archivo/2010/05/01/luminance-Processing--Making-the-Ifn-p.html

[ampleamp]

Thanks very much wimvb. I do use PI so can take a closer look 👍🏼