3 Calibrated Master Stacks For Your Pleasure! Have Fun

[Rodd]

It was reommended that I upload the links to Dropbox master stacks I used in the Hubbell Pallet Elephant's Trunk.  Here they are.  Calibrated, aligned, but not processed in any other way.  Have fun--please show me that my data can be made into a good pic.  This will do 2 things: 1) confirm I do not have an equipment problem, and 2) verify that my calibration technique is sound.  I used PixInsight, so the stacks are in the xisf format.  This way, there will be no  cheating with Photoshop!!!​

Ha: 10x20min

OIII: 9x20min

SII:9x20min

TeleVue np101is at 5.4, SBIG STT-8300M with self guiding filter wheel and Baader NB filters

https://www.dropbox.com/s/iis67xmvo2c0i7a/Master-Ha_r.xisf?dl=0

https://www.dropbox.com/s/i155m1f2do9Ia29/Master-OIII_r.xisf?dI=0

https://www.dropbox.com/s4g39g6fuza9o37p/Master-SII_r.xisf?dI=0

For some reason Dropbox would not let me copy and paste the links--so I hope I got them right.

[Pompey Monkey]

Rodd,

Only the Ha works, but it's enough for me to see that you need a lot more subs to get the noise down.

This is yours:

And here is my Rosette Ha:

Camera is SFT 8300m. Mine is 30 X 900 second dithered, flat and master bias calibrated subs. I don't use a master dark, just a bad pixel map. I have not processed this image, apart from the obligatory DBE. The "smoothness" comes from the noise reduction due to the dithering and number of subs.

Hope this helps put your mind at peace

Edit: And you'll have some cracking detail in there if you persevere!

[Rodd]

Rodd,

Only the Ha works, but it's enough for me to see that you need a lot more subs to get the noise down.

This is yours:

Rodd trunk Ha integrated.PNG

And here is my Rosette Ha:

Rosette integration.PNG

Camera is SFT 8300m. Mine is 30 X 900 second dithered, flat and master bias calibrated subs. I don't use a master dark, just a bad pixel map. I have not processed this image, apart from the obligatory DBE. The "smoothness" comes from the noise reduction due to the dithering and number of subs.

Hope this helps put your mind at peace

Edit: And you'll have some cracking detail in there if you persevere!

So you think focus is good?  And guiding?  Don't know why the others don't work.  I will try to amend

[Rodd]

Rodd,

Only the Ha works, but it's enough for me to see that you need a lot more subs to get the noise down.

This is yours:

Rodd trunk Ha integrated.PNG

And here is my Rosette Ha:

Rosette integration.PNG

Camera is SFT 8300m. Mine is 30 X 900 second dithered, flat and master bias calibrated subs. I don't use a master dark, just a bad pixel map. I have not processed this image, apart from the obligatory DBE. The "smoothness" comes from the noise reduction due to the dithering and number of subs.

Hope this helps put your mind at peace

Edit: And you'll have some cracking detail in there if you persevere!

here are the other stacks--I forgot to hit share

https://www.dropbox.com/s/4g39g6fuza9o37p/Master-SII_r.xisf?dl=0

https://www.dropbox.com/s/gd2mhyvd78nj9so/Master-OIII-1-2-3_r.xisf?dl=0

[Rodd]

So you think focus is good?  And guiding?  Don't know why the others don't work.  I will try to amend

I have seen pics with only a few subs of a few minutes that look amazing--how do they do it?

[Pompey Monkey]

I have seen pics with only a few subs of a few minutes that look amazing--how do they do it?

Who knows? It could be a variety of reasons:

Very dark skies;

Bright targets;

Binned capturing (faster, but lower resolution);

Photoshop noise reduction (an image can look very good on a web page at 800 by 600, but look at it full size and it will be a blurry mess);

Even exaggeration or outright fibbing (believe it or not, people have been know to lie on the internet to make themselves look better!);

Have you got any examples we could analyse and discuss? 

[Rodd]

Who knows? It could be a variety of reasons:

Very dark skies;

Bright targets;

Binned capturing (faster, but lower resolution);

Photoshop noise reduction (an image can look very good on a web page at 800 by 600, but look at it full size and it will be a blurry mess);

Even exaggeration or outright fibbing (believe it or not, people have been know to lie on the internet to make themselves look better!);

Have you got any examples we could analyse and discuss? 

There's a million of them--Many on this forum.  But--I must say--the blow up of my elephants Ha surprised me--stars are pinned, looks much better than I could ever make it look and I don't think it was processed really.  But if someone could fully process the 3 stacks I uploaded (all links should work now), my fears will be laid to rest if the image comes out decent.  As long as I know my gear is good and my data acquisition techniques are sound--I can live with sucking at processing--for that will get better with time, while trhe other factors are constant.

[Rodd]

You have to try and open the OIII and SII stacks from the added pots--not the original posting for some reason

[Pompey Monkey]

There's a million of them--Many on this forum.  But--I must say--the blow up of my elephants Ha surprised me--stars are pinned, looks much better than I could ever make it look and I don't think it was processed really.  But if someone could fully process the 3 stacks I uploaded (all links should work now), my fears will be laid to rest if the image comes out decent.  As long as I know my gear is good and my data acquisition techniques are sound--I can live with sucking at processing--for that will get better with time, while trhe other factors are constant.

The forum software on SGL is one of the worst that I have come across for mangling finely crafted images into blurry, low-bandwidth jpegs. But it's free, and I like the people here

BTW, your trunk is not blown up - it's at 1:1 pixel size. I did not do anything to it other than load it into PI and, make it full size and do a screen-grab. Am I missing something?

[Rodd]

The forum software on SGL is one of the worst that I have come across for mangling finely crafted images into blurry, low-bandwidth jpegs. But it's free, and I like the people here

BTW, your trunk is not blown up - it's at 1:1 pixel size. I did not do anything to it other than load it into PI and, make it full size and do a screen-grab. Am I missing something?

I don't know--it looks big to me--much bigger than when I open it up in PI.  I am probably missing something--I'll add it to my growing collection--Maybe it is because in order to see it on my laptop I use for observing and processing I have to keep the image small--onlky thing I can think of.

[Barry-Wilson]

Rodd

Your OIII stack is in fact Thor's Helmet and not the Trunk.  If you could upload the correct file I'll carry out a basic process on your data.

[Rodd]

Sorry--I'll do it

[Barry-Wilson]

No worries.

[Rodd]

Rodd

Your OIII stack is in fact Thor's Helmet and not the Trunk.  If you could upload the correct file I'll carry out a basic process on your data.

​https://www.dropbox.com/s/i155m1f2do9la29/Master-OIII_r.xisf?dl=0

[Barry-Wilson]

Rodd

The image below has been processed in PI.  I have applied a basic process:

1. Combine the 3 channels using PixelMath with SII to R; Ha to G; and OIII to B (not forgetting to select RGB output)
2. Dynamic Crop (just for for edges)
3. DBE to the resultant RGB image
4. Background Neutralisation
5. Colour Calibration
6. HT stretch (in small steps)
7. SCNR Green
8. Colour Saturation Boost
9. Magenta star correction
10. Added the cropped Ha channel (with HT stretch by STF transfer) as Luminance using Channel Combination selecting CLab
11. Small amount of NR using ACDNR (to regain a little space in the black point on the histogram)

The major issue was a persistant purple background.  I had to use an inverted and stretched luminance mask to protect the high signal stars and nebula whilst using Curves to de-saturate the background with multiple iterations (I also tried multiple DBEs and Background Neutralisations).  I suspect there is something amiss with your calibration and calibration files, eg dark, bias and/or flats and your Batch Pre-Processing.  The unstretched histogram curve was very jagged, saw-tooth like, even after cropping the frame - perhaps there are significantly large stacking artefacts within your Master stacks?  I haven't corrected the background gradient fully, but is satisfactory for this basic demonstration.

The data is there - you need more and longer subs if you can.  I would also revisit your callibration files and batch pre-processing to see if you can isolate the purple background.  Watch the Warren Keller DVDs again.  Keep at it as I have seen progression in the images you have posted and don't get down hearted!  You have focus - a key component of success and your guiding is satisfactory.  There are some corner star issues - could be many interacting issues, eg focuser tilt, adapter screw thread tilts, PA, minor flexure, cable drag etc.  You have to be methodical and work on each potential gremlin in isolation.

I have speedily processed this and I'm sure each stage can be finessed to produce a better image.

Barry

[toxic]

great process Barry --Rodd sorry i couldn't help at all i have nothing that will you .xisf file format don't have PI well i do but the old lite version and it wont open it.now if it was fits or tiff then it would be ok but it dosn't matter in the end as Barry has done a fantastic job.

[Rodd]

Rodd

The image below has been processed in PI.  I have applied a basic process:

1. Combine the 3 channels using PixelMath with SII to R; Ha to G; and OIII to B (not forgetting to select RGB output)
2. Dynamic Crop (just for for edges)
3. DBE to the resultant RGB image
4. Background Neutralisation
5. Colour Calibration
6. HT stretch (in small steps)
7. SCNR Green
8. Colour Saturation Boost
9. Magenta star correction
10. Added the cropped Ha channel (with HT stretch by STF transfer) as Luminance using Channel Combination selecting CLab
11. Small amount of NR using ACDNR (to regain a little space in the black point on the histogram)

The major issue was a persistant purple background.  I had to use an inverted and stretched luminance mask to protect the high signal stars and nebula whilst using Curves to de-saturate the background with multiple iterations (I also tried multiple DBEs and Background Neutralisations).  I suspect there is something amiss with your calibration and calibration files, eg dark, bias and/or flats and your Batch Pre-Processing.  The unstretched histogram curve was very jagged, saw-tooth like, even after cropping the frame - perhaps there are significantly large stacking artefacts within your Master stacks?  I haven't corrected the background gradient fully, but is satisfactory for this basic demonstration.

The data is there - you need more and longer subs if you can.  I would also revisit your callibration files and batch pre-processing to see if you can isolate the purple background.  Watch the Warren Keller DVDs again.  Keep at it as I have seen progression in the images you have posted and don't get down hearted!  You have focus - a key component of success and your guiding is satisfactory.  There are some corner star issues - could be many interacting issues, eg focuser tilt, adapter screw thread tilts, PA, minor flexure, cable drag etc.  You have to be methodical and work on each potential gremlin in isolation.

I have speedily processed this and I'm sure each stage can be finessed to produce a better image.

Barry

Rodd_SHO_ET_test.jpg

Thanks guys--Yes, cable drag is possible--I just learned about that and will correct.  Not sure what PA is.  Not sure how to correct for focuser tilt-maybe the camera is not 100% flush to the scope?  Adapter thread screw thread tilt the same--not sure what that is.  What do you think is more critical--more subs or longer?  I can go longer  my camera will do 1 hour subs.  I have done 40 minute subs.  If I knew I could leave the scope set up over night for several consecutive nights I could do more and longer.  The last time I tried to continue a project after breaking down and resetting up I could not get Nebulosity to stack the subs without huge rotation issues.  That was before I had PI--maybe it wouldn't be a problem now.  I did not use the Batch Preprocessing Script--did it all manually with calibration, integration, star alignment tools.  I know my darks are good--the temp was set the same and I shot them in a refrigerator in my garage.  Same with the bias--hard to screw those up.  The flats are another matter though.  I use a Neumann illuminated Flat foil.  It works great as long as the battery I use for the dew protection does not die (it did one night and I had to recharge it at 4:00am to get my flats).  I may have checked the wrong boxes in the calibration tool--maybe I told it to scale the darks when I should not have--something like that.

By the way-I am going to break down and get PS--which version should I get  lightbox,  CC,  there are different ones.  Again thanks for the info and the processing time.  

[Rodd]

Rodd

The image below has been processed in PI.  I have applied a basic process:

1. Combine the 3 channels using PixelMath with SII to R; Ha to G; and OIII to B (not forgetting to select RGB output)
2. Dynamic Crop (just for for edges)
3. DBE to the resultant RGB image
4. Background Neutralisation
5. Colour Calibration
6. HT stretch (in small steps)
7. SCNR Green
8. Colour Saturation Boost
9. Magenta star correction
10. Added the cropped Ha channel (with HT stretch by STF transfer) as Luminance using Channel Combination selecting CLab
11. Small amount of NR using ACDNR (to regain a little space in the black point on the histogram)

The major issue was a persistant purple background.  I had to use an inverted and stretched luminance mask to protect the high signal stars and nebula whilst using Curves to de-saturate the background with multiple iterations (I also tried multiple DBEs and Background Neutralisations).  I suspect there is something amiss with your calibration and calibration files, eg dark, bias and/or flats and your Batch Pre-Processing.  The unstretched histogram curve was very jagged, saw-tooth like, even after cropping the frame - perhaps there are significantly large stacking artefacts within your Master stacks?  I haven't corrected the background gradient fully, but is satisfactory for this basic demonstration.

The data is there - you need more and longer subs if you can.  I would also revisit your callibration files and batch pre-processing to see if you can isolate the purple background.  Watch the Warren Keller DVDs again.  Keep at it as I have seen progression in the images you have posted and don't get down hearted!  You have focus - a key component of success and your guiding is satisfactory.  There are some corner star issues - could be many interacting issues, eg focuser tilt, adapter screw thread tilts, PA, minor flexure, cable drag etc.  You have to be methodical and work on each potential gremlin in isolation.

I have speedily processed this and I'm sure each stage can be finessed to produce a better image.

Barry

Rodd_SHO_ET_test.jpg

Forgot to say---NICE IMAGE.  The more I look at it, the deeper I see.  Outstanding.