WOW It's been some time...Went Classic, went for M42

[CKemu 537]

 

It has been six months since I last used the telescope! Urghh that sentence is heart wrenching, but between the awful wet weather, running a bar (this time of year, it's only open evenings) and moving house - I simply haven't had chance.

It was hard enough remembering how to configure the telescope, and my guiding was "SLOPPY", 0.8"-1.2" for long periods, and then periods of 2"-3", so those stars aren't perfect - but honestly the sheer joy of getting back out there and imaging overrides the usual stress about perfection, and went with whatever came my way.

My new location is more "in town", it's not bad, but it's not as good as the empty beach I used to image from, that and my Southern window is smaller, so I expect to image more "Northern" objects over the next year or so.

Anyhow this is my first serious crack at M42, it was one of the first things I ever looked at, and had a bash at imaging, but despite it being the ever popular winter target, I've never really bothered with it in the time since,.

This image is made from four panels, imaged over three nights. Each panel being 12 x 300 s in R, G, B with no flats/bias or other faff, just straight up, 12 hours of data, stacked in DSS, and combined/stitched in Photoshop, and tonight might be clear to, so going to slew left and capture in that direction.

I left the core blown out, I did shoot short exposures for the trapezium, but I confess, I like it blown out, it gives it a proper sense of brightness to me.

Thank you for looking, if it happens to be clear tonight, I shall post my results from that in this thread.

[MartinB 2,180]

Very nice, glad you are back in business.  I too like to see a sense of the dynamic range at the centre of M42 and am not a fan of images which show the trapezium stars but are very flat

[CKemu 537]

Six hours later and I managed to grab two more panels to give me the running man, this is by far the largest image I have produced (in terms of x*y dimensions). Perhaps to balance the image a bit better, I should do a run that fills out the space at the top. Though that may be a decade from now with how the weather goes.

[Mr Spock 6,368]

Very nice. I like the natural colours.

[Ouroboros 1,589]

Yes. Very nice indeed. And as others have said, very natural colours. 

I've never done a panel. How do you make sure you can't see the join? 

[CKemu 537]

4 hours ago, Ouroboros said:

Yes. Very nice indeed. And as others have said, very natural colours. 

I've never done a panel. How do you make sure you can't see the join? 

I use a couple of tricks:

1) I have about a 25-30% overlap, to ensure that Photoshop's photomerge or Microsofts' Image Composite Editor (ICE) can stitch.
2) If using PS, I make sure it's set to "reposition", so it doesn't distort the image in any way, and blending is set to on.
3) Each panel I "calibrate", so if P1 is my reference, then when I stack P2, I check that the same points between images (normally background space near a recognizable star formation) have the same grey value, so if P1 reads 44,44,44 then the same region in the overlap on P2 should also read 44,44,44 - or very close, if not, I go back to DSS, darken/brighten accordingly and resave the image.

I also recommend if you are doing a colour image, build your colour composites after the above process, and then stitch the colour raw images together, this helps with overall alignment.  

[Ouroboros 1,589]

@CKemu OK. THanks for that description. So it's not a completely automatic process, which I imagined it might be. It sounds like a degree of judgement and tweaking is required. 

[CKemu 537]

 

Rather than making a new thread, I thought I'd drop this here with the original images. Ended up playing with Star Net++ and Photoshop to remove all the stars from the image. I love the fact that your focus is now solely drawn to the nebula. Why I have only just heard of Star Net now is beyond me. But glad I have.