Thoughts on which imaging rigs to concentrate on

[Gina]

Yes, I could do that.

[Gina]

Same result except that for no rejection images.

[Filroden]

Really odd! Do the individual subs look good?

[Gina]

Yes, just looked at one of the registered subs and it's fine.  So the problem is in the integration stage.  Here's a screenshot of a single registered sub auto-stretched in PI.

[Gina]

I guess the next idea would be to use the separate ImageIntegration process.

[Filroden]

It's worth a try. Run it with 10 or 20 subs for speed while you test the different rejection methods maybe?

[Gina]

That worked - including rejection   22 15s g440 -30C subs.  Here's a screenshot.

[Gina]

I've saved this as TIFF and transferred it to Photoshop - levels and curves only and saved in PNG format for upload.  Here's the result   Using wrong master dark - I'll grab some matching ones shortly.

 

[Gina]

Same but with "Enhance DSO and Reduce Stars" from Noel's Actions.  This shows great promise considering it's only 22 subs of 15s - just 5m 30s integration time.

[Filroden]

As you day, once you have the right master dark and finish the full integration that's going to be a great image.

[Gina]

22 was the number of subs captured and of those one failed registration leaving 21.  I'll grab more any time there a few minutes of clear night sky   Currently capturing 80 15s g440 -30C darks.

[Gina]

I could probably reduce the gain further or even the exposure time and increase the dynamic range to help capture M42.  This is quite a bright area of sky in Ha   This area would be better captured with a narrower FOV though.

Edited December 5, 2016 by Gina

[Filroden]

I did M42 at 1s and 5s at 139 gain and 30s at 300 gain and blended the results. Even 60 x 1s images showed the full loop of M42 and the Running Man, so I could probably have got away with just the 1s and 5s exposures if I'd captured many many more of them. Lower gain will give you that better range and the shorter exposures will reduce the amp glow, making it easier to calibrate. Given the strong signal in that area, I think read noise won't be too much of an issue!

[Gina]

Thanks Ken   OK I can go for shorter exposures as well as lower gain.  I'll take some more darks in readiness

Here is the current result with matching darks but the amp glow is still showing.  BPP followed by BDE then into Photoshop where I applied levels and "Enhance DSO and Reduce Stars".  I'm thinking of rotating the rig 90 degrees so that I can cover this area while cropping out the amp glow.  OTOH I'm wondering why the amp glow hasn't been calibrated out.

[Filroden]

That's a lot of amp glow for 15s exposures. I barely see any at 45s. And you're cooling below me. I only go to -20c.

[Gina]

This screenshot shows the coverage when rotated 90 degrees.

[Filroden]

Not tempted to include M78 if you can sort the glow?

[Gina]

Just seen that myself and was going to suggest this coverage

[Filroden]

I think that will look good. It also includes all three stars from the belt. Not sure how much Ha will be in M78 but it's bright enough that you'll get something!

[Gina]

Just popped out and turned the rig 90 degrees.  Also, capturing 8s g300 t-30C darks.  There is a sign that the clouds might part

[Gina]

There are gaps in the clouds now and the moon is showing

[Gina]

[Filroden]

I have a really high light haze...almost looks clear but terrible for imaging

[Gina]

It's misty here too so doubt there'll be any imaging tonight but I live in hope

[Gina]

Thick fog now!