M101 data set

[Rodd]

Here is my data set for M101--over 28 hours of data. I thought I was pleased with my M101 until I saw the followingimage by Roberto Colombari.  I am not crazy about the image and I have seen better--but its a good one to compare with mine--a refractor was involved, similar hours, similar resolution.

Roberto Colombari's Image

 https://www.astrobin.com/zcsdqj/0/?real=&nc=user

No matter what I do--my image never looks anything like this--I was deluded into thinking mine was good...becuase I was ignorant of what the truth ui.  It becomes painfully obvious when you view his image at full resolution.  The details, the color.--seeminly pale and lacking, but real!   His looks like an image of a galaxy, mine like an etching on a bar glass.  Is it the data, is it my processing, is it the software.  Can't beleive its Bortle 5, becuase someone else on Astrobin iin Bortle 9 has some awesom galaxies.  Please, have a go and lets have a look.   I am very frustrated.  28 hours is too long to be completely unsatisfied.    I had a lot more to say, but have deleted it several times....even that sounds like gibberish.  Anyway--Here is a full data set

TOA 130 ASI 1600.  300 sec subs.  The number of subs is in the stack name.  Fully calibrated and registered (one stack may not be registered--I think they all are, but if not, just align to the green channel--thats what I used)

 

 

 

 

 

Looking froward to seeing this data processed appropriately.

r58_r_r.fit

g60_r_r.fit

b55_r.fit

l80-rgb_r.fit

l80_r.fit

h87_r_r.fit

Edited April 25, 2020 by Rodd

[ollypenrice]

Hi Rodd, I'm still downloading the colour files on our slow internet but I had a go with the lum. This is a slightly cropped JPEG at full resolution. I don't process for pixel peeping so this is intended to hold up - just about - at 100% and TIFF. The data is good. It differs from my own TEC140/Atik 460 data mostly in respect of the background sky. Yours is much lighter, not surprisingly, so that makes it harder to squeeze out those very faint outer arms and separate them from the background sky. Mine would also take a little more sharpening because, again, the dark site produces less noise. After DBE in PI the rest was done in Photoshop CS3.

Olly

Edit: It does look significantly better in PS and TIFF format.

Edited April 25, 2020 by ollypenrice

[wimvb]

Thanks for the data Rodd. This will give me something to do now that I can't collect photons myself for a while. I'll report back when I have results. 

[gorann]

I echo Wim's comment!

[Laurin Dave]

Hi Rodd..  I've had a quick look at this..  Lum looks pretty good but I believe that the blue channel is actually a duplicate of your Lum..  

Dave

[Rodd]

6 hours ago, ollypenrice said:

After DBE in PI the rest was done in Photoshop CS3.

see below

5 hours ago, wimvb said:

Thanks for the data Rodd. This will give me something to do now that I can't collect photons myself for a while. I'll report back when I have results. 

see below

1 hour ago, gorann said:

I echo Wim's comment!

see below

53 minutes ago, Laurin Dave said:

Hi Rodd..  I've had a quick look at this..  Lum looks pretty good but I believe that the blue channel is actually a duplicate of your Lum..  

Dave

ALL

Dave was right--the Blue was a duplicate of Lum--also, something wierd happened and some files were 1/2 the size.  I have uploaded all new files--they are all tge same size and they are all aligned.  Sorry about that.  It was 3 am and I must have done somthing wrong.  Thanks for responding and I am looking forward to all of your images.  Oh, and I included a super luminance made from the LRGB stacks just to see the opinions on which is better--teh straight lum or the SLum

Edited April 25, 2020 by Rodd

[ollypenrice]

1 hour ago, Laurin Dave said:

Hi Rodd..  I've had a quick look at this..  Lum looks pretty good but I believe that the blue channel is actually a duplicate of your Lum..  

Dave

Well spotted, Dave! I've been busting my brains on that darned colour and actually had noticed the L-B similarity but didn't follow the thought through. I was wondering whether it was an effect of the LP filter since I don't use one. Doh!

Olly

[Rodd]

20 minutes ago, ollypenrice said:

Well spotted, Dave! I've been busting my brains on that darned colour and actually had noticed the L-B similarity but didn't follow the thought through. I was wondering whether it was an effect of the LP filter since I don't use one. Doh!

Olly

All fixed Olly.  One thing I noticed in his image is that much of what I consider dust, not Ha is colored red--like Ha.  That was one of the things that lead me to launch this excercise.  Now that I think about it, I do believe that the fine, thin "dark structures" are in fact dust--not Ha emission and should not be red.  Am I of base on this?  

[Laurin Dave]

Here's an attempt.. the faint spiral arms are starting to show,  I'm sure there's more to be had in terms of colour and extension but I've been told I need to go and cut the grass   Pixinsight (bn, DBE, pcc ArcSinh stretch, HT then  Photoshop..  LAB colour, Soft Light then layered on luminance..  Unsharp mask for the core..  then a bit of star desaturation using layers and the soft eraser..

Dave

[Rodd]

11 hours ago, wimvb said:

Thanks for the data Rodd. This will give me something to do now that I can't collect photons myself for a while. I'll report back when I have results. 

 

7 hours ago, gorann said:

I echo Wim's comment!

 

5 hours ago, ollypenrice said:

Well spotted, Dave! I've been busting my brains on that darned colour and actually had noticed the L-B similarity but didn't follow the thought through. I was wondering whether it was an effect of the LP filter since I don't use one. Doh!

Olly

 

3 hours ago, Laurin Dave said:

Here's an attempt..

Well--I had a rego.  Here is my attempt.  This is a frustrating tarhet.  Everytime I process it it comes out different.  And I have processed it A LOT of times.  I think this is better than my original.  

 

 

 

 

Edited April 25, 2020 by Rodd

[vineyard]

Tbh I'd be doing high fives if I ever came out with an image like that.  It's gorgeous.

[Rodd]

8 minutes ago, vineyard said:

Tbh I'd be doing high fives if I ever came out with an image like that.  It's gorgeous.

Thanks.  I seem to always end up in a similar place.  My versions have a lot of details, but lack a certain realism.  Its hard to explain.  Now I have to step away--I shall return afetr a rest.

[Rodd]

3 hours ago, Laurin Dave said:

Here's an attempt..

Nice--A very big thing a very long way away.  As opposed to a small thing close by that is used to represent a very big thing a long way away....like a toy soldier and the real thing.

[vlaiv]

@Rodd

You have some wonderful data here. Still in processing on my part, but I wanted to share this stage to show you something.

Maybe try not to push your data too much. Crucial areas of galaxy contain enough SNR to really bring out finest detail once sampling rate is properly set and some basic processing is done. Spiral arms are just faint. I know there is an urge to render them clearly visible - but they are faint, so leave them faint(ish).

I really love the sharpness you can get out of this data:

[Rodd]

1 hour ago, vlaiv said:

Maybe try not to push your data too much.

Your right about the outer arms--this data can't support them being bright.  Hows this?  The outer arms are less bright.  The blue is too blue where as the link at the top of the post is more sky blue.  Background is too dark.  

[Rodd]

1 hour ago, vlaiv said:

@Rodd

You have some wonderful data here. Still in processing on my part, but I wanted to share this stage to show you something.

Maybe try not to push your data too much. Crucial areas of galaxy contain enough SNR to really bring out finest detail once sampling rate is properly set and some basic processing is done. Spiral arms are just faint. I know there is an urge to render them clearly visible - but they are faint, so leave them faint(ish).

I really love the sharpness you can get out of this data:

See vlad, the outer arms are more than just faint.  They still should have a glow and color.  Not just be a gray mess like Mine. I have to start over, for the umpteenth time. But tomorrow.  I can’t stand to look at it anymore today

[Rodd]

Here is the HaLRGB directly after the LRGB insertion.  What palette is this?  The zombie palette--gray otting flesh.  There is no color other than teh Ha.  Who creates an LRGB eimage with no olor.  Naturall, bumbing up color leads to cartoons.  Where is everyone getting teh nice M101 blue?  Is PI really that bad 2or is it me?  We have confirmed its not the data (for the most part, sky background stinks).

 

 

Edited April 26, 2020 by Rodd

[Rodd]

22 hours ago, ollypenrice said:

Edit: It does look significantly better in PS and TIFF format.

That looks sharper and better than my lum and I used deconvolution, and it looks like it too--artifacts, but it is dull without it..  So--we have determined it is not the data.  The questio now is, is it the processor  (me) or the platform--or both.  What good is havng good data if it can't be processed.  I just dont get it

[Rodd]

Should have done this to start--here is my lum.  I think it is ok (not as good as Ollys) --so maybe its in the color combination that I faulter.  As you can see from the above--its pretty palettless until I hit it with saturation boosts.

 

[ollypenrice]

1 hour ago, Rodd said:

Should have done this to start--here is my lum.  I think it is ok (not as good as Ollys) --so maybe its in the color combination that I faulter.  As you can see from the above--its pretty palettless until I hit it with saturation boosts.

 

I do things a little differently from most people. For one thing I don't use decovolution. (I know this is odd!) This is how I did my version:

1 DBE in Pixinsight, then Photoshop.

2) Basic Log stretch and black point adjustment till the brighter background pixels reached 23.

3) Background noise reduction in Curves. Pin the curve at 23 and place fixing points above that. Raise the curve below 23 to taste, so lightening the darker pixels to reduce speckle.

4) Copy layer, working on the top one. In Curves, pin the background again at 23 and add one fixing point below that. Continue to stretch above that. (There is no point in further stretching the background sky.) This stretched faint stuff considerably above its noise floor but the medium bright stuff was still safe from noise.  Erase the top layer bright stars outside the galaxy and flatten.

5) Copy layer, top layer invisible, bottom active. Heavy noise reduction. I used Noels Actions, Reduce Space Noise. I want the faint outer arms and the regions between the spirals to be noise free. Too much NR is OK at this stage. We won't be applying all of it.

6) Top layer visible and active. Use Colour Select (it works on greyscale) to select the faint and semi-faint stuff where the noise is a problem. Expand by 1 and feather by 1. Set the eraser to 50% and erase the top layer where selected. Too much, too little? Go back and reduce the eraser percentage, not enough, repeat it/increase it, etc. If some small areas are still noisy remove the selection and use a small eraser brush to remove them to the percentage you want. (SO much better than masks!!!)

7) Sharpening. Copy layer, top layer invisible, bottom layer active. Select stars (Noel's Actions or MartinB's tutorial on SGL.) Expand and feather selection then select inverse so the stars are excluded. I'll now use a mixture of Smart Sharpen and Unsharp Mask, mostly the latter. I  don't look at damage it does to the lower brightnesses, I look only at the parts it enhances. I'll only be keeping those. Most of the image will look horrible but a few bits around the core will look great.

8 ) Top layer visible and active, erase at high percentage those areas which will stand it.  Reduce the percentage of the brush and erase those areas which will stand some sharpening, etc. Basically work down the brightnesses with an ever reducing percentage. It is often helpful to do the sharpening with different values in several iterations. Flatten and that's it.

Layers and eraser versus masks?  If, by some dark magic, you can create the perfect mask which goes just where you want it at the opacity at which you want it, then use masks. If you prefer to see what you are doing, where you are doing it, while you are doing it then use layers and eraser. I know which I prefer!

Olly

Edit Some of these methods cannot be used on targets with darker-then-background dusty regions.

 

 

Edited April 26, 2020 by ollypenrice
Clarification.

[vlaiv]

3 hours ago, Rodd said:

What palette is this?  The zombie palette--gray otting flesh

What do you want your color to be like?

If you are aiming for that blue in spiral arms because you think it is proper color, think again. Blue in spiral arms in this galaxy comes from the fact that people don't know how to properly color process image.

On the other hand, if you don't want to go for that natural look - then you are free to create any sort of color balance you like - it's up to your creative side to impart a mood on the image by selection of palette.

For the reference - here is what that galaxy looks like in term of color:

With that "zombie" palette you are actually closer to what galaxy looks like to human eye then other renditions.

 

[ollypenrice]

14 minutes ago, vlaiv said:

What do you want your color to be like?

If you are aiming for that blue in spiral arms because you think it is proper color, think again. Blue in spiral arms in this galaxy comes from the fact that people don't know how to properly color process image.

On the other hand, if you don't want to go for that natural look - then you are free to create any sort of color balance you like - it's up to your creative side to impart a mood on the image by selection of palette.

For the reference - here is what that galaxy looks like in term of color:

With that "zombie" palette you are actually closer to what galaxy looks like to human eye then other renditions.

 

What's the source of this one, Vlad? Is it Hubble?

Olly

[vlaiv]

26 minutes ago, ollypenrice said:

What's the source of this one, Vlad? Is it Hubble?

Olly

But of course!

https://hubblesite.org/image/3684/news

Then there is this one for reference as well:

https://hubblesite.org/image/3900/printshop

[ollypenrice]

2 hours ago, vlaiv said:

But of course!

https://hubblesite.org/image/3684/news

Then there is this one for reference as well:

https://hubblesite.org/image/3900/printshop

This set me thinking. How close can I get to this with my data and processing. Here I'm using my own M101, not Rodd's. I'm unsure how to de-blue any harder than this and I can't get that slivery-green, silvery-blue look really. I think they might have me on resolution as well... 🤣

Thoughts, anyone?

Olly

 

 

 

 

[gorann]

3 hours ago, vlaiv said:

What do you want your color to be like?

If you are aiming for that blue in spiral arms because you think it is proper color, think again. Blue in spiral arms in this galaxy comes from the fact that people don't know how to properly color process image.

On the other hand, if you don't want to go for that natural look - then you are free to create any sort of color balance you like - it's up to your creative side to impart a mood on the image by selection of palette.

For the reference - here is what that galaxy looks like in term of color:

With that "zombie" palette you are actually closer to what galaxy looks like to human eye then other renditions.

 

How do we know that Hubble got the colours right?