M16

[lhansen]

Here is an HaRGB image of M16 for comment.

The image comprises:

12 * 5 minutes images each HaRGB Binned 1*1 @ -20 C

Taken with:
RCOS 12.5inch reduced to F6.75 on a PME
SBIG STL 6303E and SBIG RGH
Guidescope Borg 77ED

Software:
MaxIm V4.6
CCD Stack V1.6
Photoshop V10.01

Processing:
Images have been calibrated, stacked (Sum), deconvolved in CCDStack with only minor amounts of curves and levels in PS

I recently borrowed a AP 0.75 reducer for my RCOS and it seems to have made a significant difference to the quality of the images.

A M20 image is on its way

[Omaroo]

Fantastic image Lars - especially for a relatively short total exposure time. Looks like the FR is doing the business! :) Very subtle. I really have to get a copy of CCDstack.

You might get more people looking if you stick this in the Deep Space photography section though! :thumbsup:

[Alchemy]

nice work, plenty and i mean plenty of nice detail.

i would bump up the red/magenta saturation a bit though, and even though i know there is no up or down in space, i like to see the pillars rising so a CCW rotation of at least 90 deg for me.

clive

[lhansen]

Hi Clive,

Funny you should say that - I did rotate the image and it aint bad. I think the image is actually better before deconvolution than after - less processing artifacts. I'll try to do better in the next 24 hours

Cheers and thanks

[Alchemy]

thats a quick reply.... will look out for the repro, thought the current one doesnt show artifacts or any obvious bad processing

[Bassnut]

Yes, nice detail there, and sorry to be brutal, but given the gear, the processing is pretty grim generally.

[lhansen]

Grim is right, I've really not spent any time on it other than the combine and deconvolve. But I will do better - I promise. Anyone who is interested, I can send them the original stacked images (on CD or DVD - the images are 27MB each) I'd love to see what people can come up with

A sort of a challenge I guess. but certainly one I could learn from and perhaps others as well? The only caveat is that anyone doing it would have to "divulge" how they did it

Any one interested (I know Bert, you are - I'll have a disk off to you soon)

Cheers

Lars

[Bassnut]

Well, actually, Id be interested, its the the defining challenge to get a top result from top gear with minimum exposure time (code for expense) on rented gear ;) :P.

[Omaroo]

Hmm... my attempt, and a quickie at that, but would be great to have original data :)

EDIT: And the second iteration here now as well. I spent quite a bit of time doing a pixel-level 50% strength blur at 500% zoom with a 9px fuzzy brush. I masked the stars first so they'd keep tighter focus and dodged around those that weren't masked. Looks better I think.

Flick between them and the difference is pretty apparent.

[Bassnut]

Holly cow Chris, now THATs a repro :lol: :eyepop: :thumbsup:

[lhansen]

Hi Fred, Chris

Give me your postal address (via PM) and I'll send you the original data.

Actually Chris I should have yours somewhere

There is always something new that we can learn. I for one would be grateful to see how far these exposures can be pushed

Regards

Lars

[Omaroo]

LOL! It's a bit bright Fred, but I want to push the colour in this one. Lars has captured it very nicely, and although the pillars are oriented in a different direction to the norm I think it looks different for it.

Yeah - there's a lot of new artefacting going on, it's no good doing it to a 72dpi JPG. Lars - can I download from you directly? I'd love to have a crack at the raw data if I may :)

[lesbehrens]

wow.

[lhansen]

I wish I could let you do the download, but I still dont have a website (despite your generous offer). I'm happy to slap it on a disk and send it to you at my expense. I'd love to see what you folks can come up with. Do you want the raw frames - or do you want the stacked frames?

There is an awful lot of data

[Omaroo]

Oh! Cool Lars! :)

Uhmm... I was going to see what happened if I stayed entirely within Photoshop for it Lars, so is it possible to stick both RAW and stacked data on the same disk? I'd like to manually stack them as well, just for fun. :lol:

[lhansen]

Here is M20, faults and all. The de-blooming algorithms in CCD stack are not so good (IMHO). So there is a bucket load of de-blooming artifacts in this image. It comprises

10 hours LHaRGB as follows:

Blue 24 * 5 mins unbinned @ -20c
Luminance 24 * 5 mins unbinned @ -20c
Ha 24 * 5 mins unbinned @ -20c
Green 36 * 5 mins unbinned @ -20c
Red 12 * 5 mins unbinned @ -20c

All other details as per the M16 image (no deconvolve). De-blooming represents my biggest challenge. Anything more than 5 mins exposure creates significant blooms and they can be challenging to remove

I've done NO processing other than calibration and stacking. Am running out of time

[lhansen]

Hey Chris

I can do both raw and stacked.

I saw how you stacked in PS and would be interested to see the results. CCDstack is very powerful but it does have a few limits with a 32 bit O/S.

Do you want M20 as well?

Cheers

Lars

[lhansen]

Before I stuffed it up

[Bassnut]

hehe, looks much better, you, CCD stack and PS are a worry :P

[lhansen]

You know its not the size of your rig but how you use it. I've finally got the RCOS to sing (blooded I believe was the term Guy used). Now I have to get really proficient at using the tooling (about 6 packages). I recon a couple of years from now and I should have it about right - based on how long it took me to get the RCOS going.

[Omaroo]

Hmm... star reconstruction is fun :)

EDIT: Stacking abberation? (see circled area)

[gregbradley]

Good to see the RCOS performing well. Nice round stars too.

I did not know an STL6303 would bloom stars - isn't it an antiblooming chip? If so perhaps you need to set the antiblooming setting. I believe they are adjustable on an STL camera.

The Ha blend has given you a salmon pinkish colour which is the result of combining Ha with LRGB as another layer?

Rob Gendler has some techniques about blending Ha on his website.

Others have generated their own approach. It is worth working out a method for blending in Ha with LRGB otherwise the dreaded salmon colour
is the result. Ideally your Ha combination technique produces nice deep red shades of colour without red speckles in the background and without wrecking star colours! Phew. Not asking much eh? Also it can be used to enhance detail and showing the presence of background hydrogen gas which always seem to be present around emission nebulae.

Greg.

[lhansen]

Hi Greg

The AP reducer at F6.75 lets me image in conditions that the full F9 would not.

The STL6303E is not anti blooming. There is an anti blooming version available but it knocks the sensitivity to hell. I think there is some form of AB adjustment for the camera but I have not chased it to ground yet.

I've got a copy of Robs techniques for Ha and in fact for the M16 image I used his technique for a luminance combine using PS. I've still got heaps to learn in this space :thumbsup:. For the M20 image I combined the Ha and Red channels which creates some interesting effects.

aint life grand :D

Cheers

Lars

[gregbradley]

Hi Lars,

I have heard of a setting for the STL11. I am assuming there is a similar setting for the 6303 but then the STL11 is antiblooming.

The reducer is a good thing expecially with your 6303 sized chip.
F9 can be time consuming for imaging.

Although it won't work on an 11000 chip or above as its corrected circle is too small.

One method for Ha combining is outlined in Wodaski's Zone System book by Russell Croman. It is assigning Ha to a layer on top of your finished LRGB image. Select lighten as the mode. You can adjust the opacity slider to suit how strong an effect it makes. Or try experimenting with the other blending methods.

it works reasonably well and is easy to do.

I find Screen mode works better if toned down.
I find it is good to run a noise reducing technique on the Ha before trying to blend it. Also use curves/levels on the Ha layer to reduce the red stars (use lasso if needed). You want the nebula to be red enhanced not the stars.


Greg.

[Omaroo]

And the second iteration here now as well. I spent quite a bit of time doing a pixel-level 50% strength blur at 500% zoom with a 9px fuzzy brush. I masked the stars first so they'd keep tighter focus and dodged around those that weren't masked. Looks better I think.

Flick between them and the difference is pretty apparent.