Second dumb question-about LRBG blending

[dhalliday]

Sorry
techno dummy rides again...
Try this;
http://www.sendspace.com/file/u2322l
(green)
http://www.sendspace.com/file/ppg827
(blue)
http://www.sendspace.com/file/e4gbpn
(red)

Let me know...
First prize is a crack at my NEXT set of data...and it will NOT be binned crap...!!

Dave

[Harry page]

Hi Dave

Had a quick go , as you know there is not a lot of signal so its difficult to sharpen the image


But here is my quick shot at it


Harry

[dhalliday]

Harry...
I like it a lot better than mine...!!!
Unbinned data is what I need...possibly that camera cannot handle  a 1300 mm ffl scope...!!
Listen...how do I "get the colors right"...??
I took all 3files into star alignment,registered them,got a RBG blend,...(that looked like Frankenstein..!!)

So I cropped/cleaned them.....and did "what I could"...
Here is my best result...so far...
http://www.flickr.com/photos/daveh56/4298863184/sizes/l/

Not as nice as yours...
What did you do about "L"...ignore it ??
Am I missing a trick or two..??
Thanks..!

Dave

[Harry page]

Hi Dave

After you have combined them you get a image that is very red , when I see this I run the background neutralisation tool first !

You will notice if you run your cursor over the image that the background is above the 0.1 upper limit default which I raised to 0.13

When you run it 90 % of your colour problems are gone , then I did

1) crop
2) DBE
3) Colour calibration
4) histogram stretch
5) wavelets
6) noise reduction
7) sat boost

8) final s curve

And I did up scale to see if I could drag anything else out at the wavlet stage and I did not use a lum


Regards Harry

[dhalliday]

Background neutralization...

Can you talk me through it ??
Godzilla...mine looks worse every time I look at it...must crawl under rock...!
On my laptop...(at 5 AM..) it seemed OK..!!
details please...on applying this life saving therapy..
Dave

PS Thanks !!

[Harry page]

Hi

Have you looked at this video

http://www.harrysastroshed.com/CC.html

Now that shows how to do a full background jobby , you can try it with just One preview

Its very simple to do , you will be amazed at the transformation

Harry

[georg.viehoever]

Hi Dave,

here is my try with your data. Process is similar to what Harry did, and documented (after StarAlignment) in the attached .psm file.

Georg

[dhalliday]

I am trying all this on my unbinned M1 data...
thanks guys...!!!

Addendum
Here is the best I can do with the 3 minute (unbinned) RBG data of M1;
http://www.flickr.com/photos/daveh56/4298694027/sizes/l/
(funny...it looks a heck of a loy better on my desktop than my laptop...!!!)

and here...(!!!) are the three TIF files...(I think it just needs more/longer exposure time...)
http://www.sendspace.com/file/7flf9a
and
http://www.sendspace.com/file/dab6qe
and
http://www.sendspace.com/file/5lfbnk

this sort of techno stuff was beyond me like 3 months ago...!

I am on a learning curve with this mono cam...but pleased how far you have brought me along so far...
I am impressed so far Harry..!!
I am a LONG way from "JEDI" yet...



Dave

[dhalliday]

And here is the SAME data...with the Lum frames also blended in...and some nice streaks from forgetting to subtract them in DSS...
http://www.flickr.com/photos/daveh56/4299696490/sizes/l/

Dave

[dhalliday]

got up at 3 to check the clouds...
Listen,Harry,group; a couple of things if I may,...

First I admit I have been an "ABE aholic"...I am ashamed but its true...I have been "using" it MANY times a day even..sometimes in the morning...!
But when I try to use DBE (it takes practice I am sure..)...it never seems to draw the little boxes ALL over the background...
I spend like 5 minutes clicking away,moving them OFF the nebuala etc.
Is the trick to click on ENOUGH different "samples" to get it thinking clearly,before hitting generate...or am I missing something more...?
SECONDLY....
When I apply the "background neutralization" to any residual problems...(GREAT TOOL...thanks Harry...how did I miss that..??)
It can give me an EXTREMELY "tight" result...
I mean all the data is "squished" into a peak on the far left....
This is good in a way...but maybe too much..!!   (for example it is hard to build a Lum mask from such tight data,,,)
Is drawing smaller/less background samples better...Maybe not drawing them in the WORST areas...or..??

One last quickie...(one last time);
I should chuck the data (RBG) AS OBTAINED out of DSS (in my case..) RIGHT into registration and RBG combine...?
EVEN if the histo's are slightly different,etc,etc.
No questions...just chuck it in..
What if I have collected more/better subs in BLUE (for example)...and it is less "noisy"...ie stronger...just put it in the pot..??
What if I am deciding to use 2.7 minute green subs,and 3.2 minute Blue...( for balance)...
Chuck them straight together...??
Thanks again....I feel I am being a real motor mouth...(but I am...)

Dave
PS here is my re/re/redo of M51...
Took about 10 minutes total..(!!)
http://www.flickr.com/photos/daveh56/4300139602/sizes/l/
(I like blue...)

[Harry page]

Hi

ABE aholic well I hope you hang your head in shame !

I think you will find that ABE will not be sampling the background properly either ( Check draw box and see )

Anyway on to DBE , it works quite well with the default setting if you have good flats and not to many gradients.
so what do we do when the default fail
1) lower the min sample weight ( I used 0.2 on your image )  this will draw more samples
2) Increase the tolerance to include more of the samples ( all ) in the model ( so they are not red ) ( I used 1.5 on yours )
3) edit your samples so they are not on areas of interest
4) you must put as many samples all over the image as you can i used size 8 and 20 samples per row

You can be quite vigorous with the settings here as I know there is no faint stuff in the background, if there was !  that's another story

There is good news and bad news about your tight histogram , the good is what most people get after removing all the gradients etc , the bad is yes that is all the signal you have ( tiny )

I would personally just chuck all of your channels together and sort the balance out later, in an ideal world you should collect all the channels with the correct balance

Here is your m1 and i am afraid more signal is required   ie longer subs and more of them , welcome to the world of imaging

[Harry page]

Hi

Sorry missed your M51

I like blue to , but not that much 


Harry

[dhalliday]

Harry...
I SWEAR I will never take another (drink) of ABE again...
Thanks SO much...
I am finally where I should be...
So....skinny histograms...data limited...
That makes sense...
Now I need clear skies....and some sleep...

Dave
PS what part of UK are you..?
Love your astro shed...!!

[georg.viehoever]

Hi Dave,

Regarding DBE:
- I usually increase the tolerance until samples are generated for the whole image. In your case, the data had a gradient from top left to bottom right, and with the default tolerance of 0.5 only part of the image is covered. Increasing tolerance to 1.5 helped in your case.
- I than manually move the few samples that are too close to stars or galaxies. This is usually only a hand full of points.
- I intially set "Target Image Correction" to Substraction, no Normalization, Discard Background, Dont Replace target images and do the apply
- The generated result can then be checked using STFs. If there are any regions in the result that are too bright or too dark, I check if there is a star or a galaxy close to the corresponding sample, and I move or delete it. Apply again and repeat until you are satisfied.
- Finally, check Replace Target Image to get the final result

Regarding histogram imbalance: I think that is just what Background Neutralization and Color Calibration will usually take care of.

Enjoy your nights with PI  

Georg

[georg.viehoever]

Hi Dave

Had a quick go , as you know there is not a lot of signal so its difficult to sharpen the image
...

Harry,
I like the delicate details that you were able to extract in the inner parts of the nebula. My shot at it is not nearly as good. I guess the trick must be in your use of wavelets or the noise reduction. Would it be possible to share the exact settings via screenshot or PSM file?

Thanks,
Georg