• Welcome to Orpington Astronomical Society.
 

News:

New version SMF 2.1.4 installed. You may need to clear cookies and login again...

Main Menu

layers/ masks, hopefully conquered after 100 hours and 3 weeks

Started by Fay, Jan 20, 2009, 22:11:48

Previous topic - Next topic

0 Members and 2 Guests are viewing this topic.

Fay

Not perfect, still got things to learn, but better than the originals. I have the basics sussed now, thanks to Daniel for his help.


27x240 Canon/ ED80/ 008fr, cls




17x240 Canon/ZS66/cls



21x300 Atik 314L/Ha/cls/WO ZS66



It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

JohnP

Well Fay I think you are getting there.. like you say a vast improvement on your first efforts. The top one does it for me excellent focus & tracking & processing - The noise is starting to show but I guess you have pushed it quite hard to show all that nebulosity?

The middle one has slightly elongated stars & still not sure if all is right with the stacking as there seems to be 'double stars' to the top left (maybe a rogue frame or something)..? The colours are great but not quite as deep as the first (but less exposure).

The 314L image looks a tad out of focus (could be image scale or seeing) but again excellent - you have certainly mastered the core processing.

As you have all images orientated the same way it would be great to see if you could combine them all into a single image... you would have nearly 4.75hrs of exposure.... Maybe something to try when you have a rainy day or weekspare...  :lol:

Good work,  John

Fay

Thanks John. Never thought of putting them together. There were a lot of problems with the stars in bottom left corner, before rotated. Perhaps 0.8 FR not suitable for Canon chip
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

MarkS


Daniel

Hi Fay, that's looking great, I know how tough it was to blend the 2 images together and you seem to have nailed it! you've also managed to pull out that outer nebulosity nicely, as John said,it's getting a little noisy because of the stretching but nothing a bit of noise reduction won't help.

Might be worth seeing what it looks like if you add the Ha image into the red channel.

Daniel
:O)

Mike

Fay that is really nice. Your skills are improving day by day.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

RobertM

Fay,

That looks wonderful, the top one does it for me, to my eyes it has excellent saturation.  I reckon a good pointer to the quality is when the running man stands out and he looks really good.  Certainly adding the Ha to the red channel as others have suggested could help but don't use it as luminance as it looks ever so slightly blurred compared with the others.

Well done!
Robert

Fay

That is very kind of you all. Looks like I have something else to be doing, while weather is bad, putting images together, I had not thought of that.
May redo Ha M42, as I may have made it a bit sort thru processing. Then again, I have so many variations of this nebula, I  could have done the wrong one!!!!!!!!!!!!!!!! :surprised:
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Fay

If I merged the two Canon images, would I have to start from scratch, no previous processing, does anyone know?
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Fay

To combine M42 images, does it matter that a focal reducer was used on one & so is smaller?

Thanks
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

JohnP

I don't think so I'm sure astro art or maxim or aip4win or whatever you use should be able to scale/ rotate etc etc. As long as you have same stars in both images that you can use as a reference you should be able to coregister the 2 images...

MarkS

Fay,

Sure it can be done - I hope you don't mind but I tried it below (a merge of the two Canon images). The result is cleaner and more detialed than both originals.  It is best to do the merge on the two full-size images and then shrink down as a final step.

One other tip is that you need to "weight" the images.  Your first Canon image is less noisy than the second (27 frames vs 17 frames) so it needs to contribute more to the final image.  I added 2.7x the first image to 1.7x the second.  In that way you get the cleanest possible final image.

To be obsessivley accurate, you need to weight them according to the inverse squares of the signal to noise ratios in each image - oh no, I've reverted into Techspeak mode again! 

Mark



Fay

Thanks mark, that is really interesting. I did try to align the 2 images in maxim, but nothing happened, any idea's why? How did you merge the two?
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

MarkS


Fay,

I don't know about Maxim so I can't help you there.  I used IRIS, of course - I continue to be a great fan of its power and flexibility and I'm very used to its "clunkiness" by now.

For this particular task it has a stellar registration function which does the following:
1)  It identifies which stars it need to match in both images
2)  It applies the relevant shift, rotation and lens distortion correction it needs to register both images.

Maybe DeepSkyStacker would work?  But I don't remember if it does the correction for lens distortion.

Mark

Fay

It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!