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Christmas Present

ollypenrice

By ollypenrice
in Imaging - Deep Sky

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Rodd

Rodd

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3 hours ago, ollypenrice said:

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

I wouldn't say "significant"--as it is a minor part of the composition--but point taken.  

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alan4908

alan4908

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Thanks for this Olly. Since I'm need of post processing practice I decided to have a go - it was also a pleasure to work on such high quality data. 

The result is mainly processed in PS with Pixinsight used for DBE and colour calibration and CCDstack for deconvolution. I decided to go for a Ha blend in both the luminance and red channels.

Alan

8. Final.jpg

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Filroden

Filroden

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Thank you and Merry Christmas too (though I have to say, if you're struggling to think of presents for us next Christmas, I love clear skies :)). This image tested me. I couldn't see anything that needed doing other than stretch/combine. When I look at my own, I have to decide how to handle the noise, etc. So I thought I'd try and bring out as much of the reflection nebula as I could (all in PixInsight). I think it leaves the overall image a little imbalanced but I like to think this is the snow on a nice winter's scene.

Cave_LHaRGB.jpg

 

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Rodd

Rodd

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On 12/19/2016 at 07:07, Filroden said:

Thank you and Merry Christmas too (though I have to say, if you're struggling to think of presents for us next Christmas, I love clear skies :)). This image tested me. I couldn't see anything that needed doing other than stretch/combine. When I look at my own, I have to decide how to handle the noise, etc. So I thought I'd try and bring out as much of the reflection nebula as I could (all in PixInsight). I think it leaves the overall image a little imbalanced but I like to think this is the snow on a nice winter's scene.

Cave_LHaRGB.jpg

 

Now that IS significant.  Great job.

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toxic

toxic

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Posted

didn't do to much to this i only used photoshop cs2. i ran hlvg on the rgb then removed the stars from the HA image.

then ran it through a highpass filter,then used this as a soft light layer to the rgb which gives some more detail to the dust an gas but did nothing to the stars after this i just increased the saturation.

Olly-jpg.jpg

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ollypenrice

ollypenrice

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On 25/12/2016 at 02:48, wimvb said:

Here's my first attempt at this target.

I'm not really satisfied with the weak Ha areas

wimvb_2r.jpg

Comments welcomed

Nice.

There wasn't enough Ha data in the capture for it to add to the faint areas, I don't think. I only used it to lift the brightest Ha regions. It would have been nice to have had double the Ha exposure time but sometimes you call it a day when new targets arrive...

We always have enough data in the Tak rig because it has two scopes and cameras each running at F5 instead of F7. The difference is enormous. We need a second TEC...

Olly

 

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Scott

Scott

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On 12/18/2016 at 17:58, ollypenrice said:

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.

Olly

Thanks for the data Olly

It's certainly a treat working with great data from a dark site. As someone else mentioned,  there really is very little to do to bring out a nice  image. i've  not had the banding issue before but that may be down to my tiny chip? the action Noel has deviced is amazing at sorting it though. I've only played with the Ha as yet but  looking forward to have a full play when things settle down

 

 

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ollypenrice

ollypenrice

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31 minutes ago, Scott said:

Thanks for the data Olly

It's certainly a treat working with great data from a dark site. As someone else mentioned,  there really is very little to do to bring out a nice  image. i've  not had the banding issue before but that may be down to my tiny chip? the action Noel has deviced is amazing at sorting it though. I've only played with the Ha as yet but  looking forward to have a full play when things settle down

 

 

The Sony chips are far better for not producing artefacts. The banding is a signal to noise issue, so the trick is to up the exposure times on faint targets or in narrowband. I should have taken longer Ha subs. I have some banding on the present project in this rig as well. The target is a very faint NGC so the stretch needed to get it to show is making the banding show as well. I'll just try going to 15 mins for RGB instead of 10. On brighter targets I don't see it at all.

Olly

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wimvb

wimvb

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Second attempt; this time only the RGB data. Contrast and saturation enhanced to bring out the reflection nebulae.

There seems to be a lot of dust in front of this target, which came out brown in this rendering. Next I'll try to lift this with the luminance data.

I found that even the RGB data suffers from faint banding that is much more obvious in the Ha data. I this from the camera's read pattern? Anyway, darkening the background more, just increases the pattern, otherwise I would have increased the black point slightly.

wimvb_justrgb.jpg

 

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Racey

Racey

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Olly

Just found this thread. Thanks a million for the data. As complete rookies it'll be interesting for Susie and me to have a play with this as we can compare how others have interpreted and processed it. And how our attempts fare... Could take us a while but it'll keep us out of trouble for a bit ! :thumbsup:

Simon 

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Racey

Racey

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Well... That kept me quiet for a while ? 

Having only bought our first scope at the beginning of last month, let alone having not strapped a camera to either of them, I'd describe that as a bit of a steep learning curve !!

but it's amazing what a bit of trial and error can lead to. (I'll admit to quite a bit of cussing as we kept realising "Ours looks nothing like Olly's !!)

1st attempt in PS.jpg

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gnomus

gnomus

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15 minutes ago, Racey said:

Well... That kept me quiet for a while ? 

Having only bought our first scope at the beginning of last month, let alone having not strapped a camera to either of them, I'd describe that as a bit of a steep learning curve !!

but it's amazing what a bit of trial and error can lead to. (I'll admit to quite a bit of cussing as we kept realising "Ours looks nothing like Olly's !!)

 

Surely that cannot be your first time?  If so, you are beginning to frighten me.....

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Racey

Racey

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4 minutes ago, gnomus said:

Surely that cannot be your first time?  If so, you are beginning to frighten me.....

That's very kind of you. Cross my heart, I hadn't laid eyes on any camera data other than what I'd seen while trying to evaluate whether Susie and I should consider entering the Astro Imaging world  (We've not even got an easily useable camera as the 1Ds and 1D we own are Digic 1 processors with no live view. Hence our saving for an ASI1600MM Cool - where all the reading has been done)

With the "holiday snapping" we've done thus far we have PS CS5. So we gave it a whirl in that last night...

It was a fun but initially bewildering exercise ?

 

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