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

[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

[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... 

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

[MarkS]

Fay,

You certainly seem to have mastered it now.

Mark

[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.

[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!!!!!!!!!!!!!!!!

[Fay]

If I merged the two Canon images, would I have to start from scratch, no previous processing, does anyone know?

[Fay]

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

Thanks

[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?

[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]

Thanks Mark I will have a go

[Mike]

The align routine for mis-rotated images in Maxim is dead easy. I can't remember the exact menu commands, but you go to the alignment menu and once inside select the 2 star align. Select two stars at opposite corners of the field in both images and then Maxim will rotate and align them for you.

[Daniel]

Hi Fay, hope you didn't mind, I took Marks version and added the Ha image into the Red channel, seems to bring out a little more contrast, although i performed a bot of unsharp masking in areas aswell (although i was quite sloppy, so it's a little all over the place)

Anyway, now I've seen this, Im going to be out there myself with the Ha next time we have the weather!

Daniel
:O)

[Fay]

Daniel, I like that!

I have been all day, getting too obsessive, trying to align these two images, Can't seem to do it in Maxim. I am just about to give up on it forever. I even restacked the image with all the mis alignment subs in top left. It seems every frame was the same. I don't know why I cannot align, like Mark did. Maxim says cannot align on stars & I don't know IRIS.

[Daniel]

You'll have to do a manual 2 star align in Maxim, instead of the correlation (which is how I aligned these images) I find that maxim has problems aligning if you've done any processing on the image.

To do a 2 star align, first pick the 2 star align method when the align box comes up, then it'll bring up a view of one of the images, select a bright star, once you do that, the image will change back to the other image your trying to align, select the same bright star.

Once you do that, it'll switch back to the first image again, once again select another bright star, by the way, it helps if the stars are in far corners from eachother. Again, the image will switch to the second image, select the same star and your done, just hit OK on the align box.

If this is all just gobbledygook, give me a call,

Daniel
:O)

[Fay]

Well, I got back from the meeting, last night, & only one lot of subs had stacked. I had done it once in the day, but only 16 had stacked then, also.I had been trying to combine the two evening's worth of M42, 17 + 27.
The 17 stack, did come out better than the original, so used it with a processed image of the other 27 subs  & managed to align in Maxim using 2 star method.

Will see how it turns out & then that will be that!!!!!! It would be easier just to go outside & start again. The reason I only got the 17 in the first place was because of the leaving of the cap on, in error, for an hour!! 

[Mike]

Maxim says cannot align on stars & I don't know IRIS.

Fay, if you are coming to the imaging session next Thursday then bring your laptop, with Maxim and these images on it, and we will figure out what is going on. I have always found aligning in Maxim dead easy, even on images well out of alignment.

[Fay]

Mike, I did manage to do 2 star alignment, but when I put the images in DSS, it refused the second group. It must be to do with size orsomething. These are Canon images.

[Fay]

This was 2 star alignment with two stacked images

[RobertM]

Fay, I can give you a MaximDL lesson if that would help.

[Fay]

I will take you up on that, Robert, thanks

[Fay]

Daniel, when you added the Ha version into the red channel, do you have to make the image RGB & then past into the red?

[Daniel]

Fay, yup, that's precisely what i did, I got some Ha on M42 myself last night, seems that the 13nm Ha filter worked with the Hyperstar pretty well, although It did bloom a lot in the blue channel. Fortunately, I only extract the red so this doesn't affect me. managed 4 minute subs and could probably go to about 8 minutes If I were to push it, although at that length the core was blowing out quite a bit.

Not sure if I'll publish the results yet though as the subs I got were pretty poor on account of the dew heaters not being on last night and everything fogging over through most of the subs.

Daniel
:O)

[RobertM]

If you're using Ha for luminance then you'll find it better to partially blend the Ha to the Red channel first otherwise the red channel gets over enhanced.   I do HaRGB as Ha+HaR+G+B and not HaHaGB the colour balance works out better that way.

[Fay]

I have not got the hang of getting the Ha into the red channel

[Daniel]

Fay, have a look at this tutorial, it covers a few different techniques for merging the Ha http://www.robgendlerastropics.com/HARGB.html

For your image though because the Ha was a lot better than the Red I just pasted the Ha straight into the red channel, so this is a Ha,G,B composite rather than a Ha,R,G,B.

Hope this helps

Daniel
:O)

[Carole]

Having read this thread with great interest, I contacted Daniel through windows live messenger (we have had a couple of chats this way before) and asked him what masking was.  He sent me a couple of files and took me through the process remotely (so he could see what I was doing on my computer).  After a short while (with a few hiccups) I completed doing a mask. 

We thought we'd post this as we thought this was a good method of showing some-one how to do something and actually be able to see what they are doing at the same time, assuming of course they have remote access on their PC.  Neither Daniel nor myself had ever tried remote access (at home) before.

So another bit of info I have up my sleeve.  Just need to get my finger out and get some new equipment and get out there and do some imaging.  Might have more time now I have finally retired.

Carole

[JohnP]

Cool - 'Cyber Tuition....'

Carole - I have to say you seem really enthused with the imaging side now with all the questions etc. you are asking... I look forward to seeing your first image in Astronomy Now or image of the month at OAS...

John

[Carole]

I look forward to seeing your first image in Astronomy Now or image of the month at OAS...

Thanks John, but I have a long way to go to catch up with all the fabulous imagers in the group.  I am just trying to get my head around it all and am approaching it slowly and cautiously and picking brains and reading (and saving) threads so I have a good idea (and references) by the time I get to do it myself. 

Have been very lazy for the last few months as I was getting frustrated with certain aspects of planetary imaging, and have decided I need to go on to the next stage or I will be stuck there forever. 

Also can't really afford the full financial layout all in one go, so might have to do it in stages.

Carole