M81/M82 IFN - Done and dusted.

[Adreneline]

This is the longest I've spent on one region for some time.

Two sessions resulting in (37 x 180s) + (90 x 180s) (equating to 6hrs 21mins) of OSC data of the IFN region around M81 and M82.

Taken with a Samyang 135mm + ASI294MC, unguided.

I felt the starless image was more justified here because the IFN is beyond the galactic plane and hence beyond the stars. I also removed M81 and M82 - badly.

Processed in APP, PI and Affinity.

I feel as though I have now adequately scratched my IFN itch and will be moving on to other things.

As always C&C welcome.

Thanks for looking.

Adrian

[jetstream]

Excellent.

[AbsolutelyN]

That's stunning Adrian, great work. The structures in the starless version are very detailed and intricate. 

[Adreneline]

1 hour ago, jetstream said:

Excellent

Thank you!

1 hour ago, AbsolutelyN said:

That's stunning Adrian, great work. The structures in the starless version are very detailed and intricate.

Thank you Tristan. I know a lot of folk don't like starless but I think it lets the structure and depth come through sometimes; star filled nebula can sometimes appear quite planar and two-dimensional - in my honest opinion, of course  

Adrian

P.S. To those who like to look for these things the structure to the left looks like a wolf's head 🍷

Edited April 16, 2021 by Adreneline
Senior moment

[geeklee]

Excellent Adrian!  When I got down to the starless version it blew me away even more - great way to show off the area even more!

2 hours ago, Adreneline said:

left looks like a wolf's head 

I won't unsee that now 😅

[Magnum]

Great job , ive been plugging away at this also with my samyang 135, i pick it up in my mono ccd but barely get anything in my OSC cmos, can i ask what bortle your imaging in? What f stop did you use the samyang at, and what gain please?

cheers

lee

[Adreneline]

40 minutes ago, geeklee said:

Excellent Adrian!  When I got down to the starless version it blew me away even more - great way to show off the area even more!

Thanks Lee - I'm a bit of a fan of starless images - they give you a different insight into what's there.

35 minutes ago, Magnum said:

Great job , ive been plugging away at this also with my samyang 135, i pick it up in my mono ccd but barely get anything in my OSC cmos, can i ask what bortle your imaging in? What f stop did you use the samyang at, and what gain please?

Thank you Lee. The Bortle round here is apparently 4 but where I live I think it is closer to 3; the two nights of imaging were also exceptionally clear which helped a lot. I use the lens wide open at f2; I've found no benefit in stopping it down at all. The camera gain is set at 120 operating at -20 degrees. I have no idea what the offset is as the ASIair does not allow you to control that feature.

The IFN is barely apparent on the stacked master. Following edge cropping and BackgroundExtraction I start by using PI's ScreenTransferFunction to give it a severe stretch followed by SCNR to reduce the green in the image. I then use HistogramTransformation to line up the colour components before applying LocalHistogramNormalisation to increase the contrast. I then use 10 layers of HDRMultiscaleTransform to try to tease out the structure followed by the EZ star reduction script.  Finally a tweak in Affinity to tone down the over exposure M81/M82 cores using the Burn tool.

HTH or is of interest/use to someone.

Adrian

Adrian