Christmas Present

[ollypenrice]

Hi Folks, I've had another year's cheerful support and encouragement on here and would, by way of thanks, like to offer a small Christmas pressie to my fellow imagers in case the sky isn't kind to them over the festivities! Here is a calibrated dataset from the TEC 140/Atik 11000/Avalon Linear outfit for you to play with if you fancy.

Ha 5 hours, Luminance 4 hours, RGB 12 hours (4 hours per channel.) The data has been calibrated by means of bias subtraction, defect map correction and flat fielding. (I don't use normal darks any more.) The luminance is a little short but the RGB can help it out if you make a synthetic L layer from it. The panels are cropped to fit each other but there is a sliver missing from the top of the Ha. Sorry! No post processing of any kind has been done.

Here are the links...

https://www.dropbox.com/sh/cmshpjatyahdrds/AABLl3tWrhELzB2h5ARA00vDa?dl=0

 

A very happy happy Christmas to you all,

Olly and Monique.

PS, forgot to say, it's the Cave Nebula.

 

[Allinthehead]

Looks like the link has Heart and california?

[Starlight 1]

Only number 3 showing .  I take this time to just say thanks for all your help this year and have a nice Christmas .

[ollypenrice]

3 minutes ago, Allinthehead said:

Looks like the link has Heart and california?

So it does! That is certainly not what I asked for! Let me try again...

Yes, I think that's fixed it. Cheers,

Olly

 

[mikeyj1]

thanks olly.. will be a good learning experience (hopefully!)

Mike

[ollypenrice]

8 minutes ago, mikeyj1 said:

thanks olly.. will be a good learning experience (hopefully!)

Mike

Give me a shout if I can help!

Olly

[Allinthehead]

Thanks Olly, i enjoyed that. Happy Christmas. 

 

[gingergeek]

Thanks Olly for the data and many thanks for all the help and time you give people, it is appreciated.

[saac]

Thanks Olly that's a really great gesture; I'm nowhere near ready to capture that kind of data from my own setup but at least I can make a start on acquiring some processing skills using real data.  I wonder if the mods would think it worthwhile making such a thread a sticky or having a dedicated thread itself.  Could be a useful processing tutorial thread, maybe it already exists - I need to take a look.    Anyway thanks again Olly, have a happy and peaceful Christmas when it comes.

 

Jim

[Barry-Wilson]

Thank you Olly - only endless cloud forecast for the south west UK, not sure that many other areas of the UK or Europe have fared much better of late.

Great idea for a processing tutorial thread too.

[RichLD]

Wow thanks Olly, that's brilliant! My Sunday evening is now sorted!

Merry Christmas to you and yours sir! 

[Maximidius]

Wow thanks a lot Olly, coupled up with some other data that was kindly donated, i'll be having some fun over the holidays.  

[Barry-Wilson]

I've indulged the gloriously rich data here and presented a colourful Cave . . . lots of interesting detail lurking in the dark dust and delicate reflection nebula.  Top drawer data Olly and a real treat to process.

Lots of work to present a varied starfield with colour and size differentials; gentle with the Ha data to highlight the 'cave' area; banding script to eliminate the vertical banding in the Ha; very careful DBE at the outset to target background (there isn't much true background as the image is reach with background dust and gas); HaRGB script and then luminance combined in CieLab mode; a little NR with TGVDenoise; a light touch with the LHE process, some contrast curves and saturation boost; tiny crop along the top edge to eliminate the Ha channel gap.  Hey Presto!

 

[AKB]

Thanks so much... there seems to be a paucity of good examples to learn about processing - but since that's your business, then this is a very generous present!  Or maybe I am just looking in the wrong places.

I've never tried to process LRGB (let alone Ha as well) before, so this is fun.

Can you explain to me what causes the vertical banding at (very) low levels in the Ha?  I see it also in the processed example here by @Allinthehead?

AK

[gnomus]

Olly - Thanks for the early gift.  With my weather forecast being as it is, you had better keep the data flowing!!  I hesitate to offer up my version, but here goes:

 

[RichLD]

1 hour ago, AKB said:

Thanks so much... there seems to be a paucity of good examples to learn about processing - but since that's your business, then this is a very generous present!  Or maybe I am just looking in the wrong places.

I've never tried to process LRGB (let alone Ha as well) before, so this is fun.

Can you explain to me what causes the vertical banding at (very) low levels in the Ha?  I see it also in the processed example here by @Allinthehead?

AK

Not sure about the cause but try this from Bob Franke's website http://bf-astro.com/ccdBandAid/ccdBandAid.htm

I think you need the uncropped images to determine the phase though...

[ollypenrice]

1 hour ago, AKB said:

Thanks so much... there seems to be a paucity of good examples to learn about processing - but since that's your business, then this is a very generous present!  Or maybe I am just looking in the wrong places.

I've never tried to process LRGB (let alone Ha as well) before, so this is fun.

Can you explain to me what causes the vertical banding at (very) low levels in the Ha?  I see it also in the processed example here by @Allinthehead?

AK

 

The banding is inherent to the camera under very low signal and the best solution is to take longer subs, which I should have done. I'd forgetten about it, truth to tell. I get rid of it by using Noel's Actions, Reduce Vertical Banding. However, if you stretch carefully it remains at a pretty insignificant level.

 

1 hour ago, Barry-Wilson said:

I've indulged the gloriously rich data here and presented a colourful Cave . . . lots of interesting detail lurking in the dark dust and delicate reflection nebula.  Top drawer data Olly and a real treat to process.

Lots of work to present a varied starfield with colour and size differentials; gentle with the Ha data to highlight the 'cave' area; banding script to eliminate the vertical banding in the Ha; very careful DBE at the outset to target background (there isn't much true background as the image is reach with background dust and gas); HaRGB script and then luminance combined in CieLab mode; a little NR with TGVDenoise; a light touch with the LHE process, some contrast curves and saturation boost; tiny crop along the top edge to eliminate the Ha channel gap.  Hey Presto!

 

Very nice, Barry. To be honest it's interesting to see so little differenbce between an all-PI approach like yours my my Ps-dominated version here:

You could hardly call them different animals. Good job from Gnomus, too. Gentler, wth nice tiny stars.

Olly

[StuartJPP]

Just a quick LRGB process...Still trying to get something out of the Ha data.

[AKB]

So this is my first attempt.  Entirely in Nebulosity, using, as suggested, L+RGB for Luminance and adding in some Ha in the Red.  Since I've not done anything like this before, it's wide open for constructive criticism!

 

Thanks again, Olly, for the gift of the dataset.

AK

[Barry-Wilson]

Fascinating Olly.

Regardless of which processing s/ware application is used, we must have a similar imagined internal vision of the finished composition for this image.  The s/ware is just a tool to transform the data in the image how we wish after all . . . (let's not have a PI vs PS debate everyone please) .

[johnrt]

13 minutes ago, Barry-Wilson said:

(let's not have a PI vs PS debate everyone please) .

[Barry-Wilson]

1 minute ago, johnrt said:

Ha, ha! LOL!

[ollypenrice]

I rather feel that the similarity between my Ps version and Barry's PI would make for less than thrilling debate!

27 minutes ago, AKB said:

So this is my first attempt.  Entirely in Nebulosity, using, as suggested, L+RGB for Luminance and adding in some Ha in the Red.  Since I've not done anything like this before, it's wide open for constructive criticism!

 

Thanks again, Olly, for the gift of the dataset.

AK

You're doing well. For me the green is too high on the left and too low on the right (turning things magenta.) The data had a colour gradient, as almost all data does, and this needs dealing with sooner rather than later. I did it in PI as a first step using DBE and, probably, SCNR green.

Olly

[Rodd]

This may not be appropriate--but I could not help pass up the opportunity.  One of my goals is to make NB appear like a visual pallet, but with more structure.  The above images are obviously great visual pallet representations.  This image is all NB made to appear as a visual pallet--using the above data as a guide.  I think it is an interesting experiment.

 

 

 

[ollypenrice]

2 minutes ago, Rodd said:

This may not be appropriate--but I could not help pass up the opportunity.  One of my goals is to make NB appear like a visual pallet, but with more structure.  The above images are obviously great visual pallet representations.  This image is all NB made to appear as a visual pallet--using the above data as a guide.  I think it is an interesting experiment.

 

It certainly is interesting, but on targets with a significant reflection component, as the Cave does have, the task is surely impossible. All you have of the reflection nebulosity is the gaps it creates in the emission signal which you do have. When I say reflection nebulosity, this includes the very faintest reflection such as the scattering of light from dust. It also includes the blue reflection nebula lower left of centre, which Barry has processed better than I did. It has no emission signal so even with an H beta filter, which is blue, there would be very little coming through.

Olly