2 Panel Mosaicin Ha

[Rodd]

2 Panel mosaic, Televue np101is with .08x reducer, Astrodon 3nm Filter, Total integration time 16 hours (23-30 min and 9-30 min).  Minimally processed for stand alone purposes.  Will move forward with color version with the unprocessed version.

[Barry-Wilson]

This image really shows your progress Rodd - a great mosaic mono with good composition.

Strong signal features in the image maybe highlighted and saturated a tad too much, nevertheless a good image.

[Davey-T]

Blimey Rodd, mosaics whatever next, putting me to shame as mosaics gave me all these grey hairs 

Well done

Dave

[Rodd]

26 minutes ago, Barry-Wilson said:

This image really shows your progress Rodd - a great mosaic mono with good composition.

Strong signal features in the image maybe highlighted and saturated a tad too much, nevertheless a good image.

Thanks Barry.  I did not touch saturation.  All I did was combined the stacks, Mure Denoised and ABE, then combined into mosaic.  Then I sharpened just a tad (unsharp mask just once) and used Local Hist. Equilization once with a 1.3 factor.  That's it.  Maybe the fact that one half has 9 30 min subs and the other half has 23 30 min  subs causes a saturation imbalance?  Not sure.   

[Rodd]

26 minutes ago, Davey-T said:

Blimey Rodd, mosaics whatever next, putting me to shame as mosaics gave me all these grey hairs 

Well done

Dave

Thanks Dave.  It wasn't too bad really. 9 panels would be something else.

[PatrickGilliland]

Now thats a super field of view - a little work on the saturation will help as Barry said but that has the makings of a real cracker.

Paddy

[johnrt]

15 hours ago, Rodd said:

Minimally processed for stand alone purposes.

When you have enough good data to work work with, in terms of processing less is certainly more. Great mono image there Rodd.

[Rodd]

5 hours ago, PatrickGilliland said:

Now thats a super field of view - a little work on the saturation will help as Barry said but that has the makings of a real cracker.

Paddy

Thanks  Paddy.  Maybe 30 min subs are too long for this target in Ha (OIII is quite weak).

[PatrickGilliland]

19 minutes ago, Rodd said:

Thanks  Paddy.  Maybe 30 min subs are too long for this target in Ha (OIII is quite weak).

Hmmm - not sure - for some areas you will def want for others not so much.  HDR combo with some shorter images for bubble and the protostar would work well.  You could try 15x60 for that detail should all balance out nicely then.

Paddy

[Rodd]

4 hours ago, johnrt said:

When you have enough good data to work work with, in terms of processing less is certainly more. Great mono image there Rodd.

Thanks John--maybe to minimal?  There seems to be a saturation issue that I am trying to understand that must be fixed with more processing.  

[ollypenrice]

Another super result to confirm your stunning progress, Rodd. This is great. I think that the Astrodon 3 is a self-processing filter. All the things you do in terms of contrast boosting, sharpening and star reduction just come straight off the filter!

Olly

[Rodd]

13 minutes ago, ollypenrice said:

Another super result to confirm your stunning progress, Rodd. This is great. I think that the Astrodon 3 is a self-processing filter. All the things you do in terms of contrast boosting, sharpening and star reduction just come straight off the filter!

Olly

Thanks Olly--and that is definitely true.  I find that almost no processing is needed after the image is Non linear.  Then again--this is true for Ha for me.  But as soon as I combine other filters, everything seems to change for some reason.  I always thought that as you add colors it is like a coloring book--there are areas of red, green and blue.  But I find that there can be destructive interference between filters.  A wonderfully rich and full Ha image suddenly becomes less so with the addition of OIII for example.  I have had images that have Ha structure over wide areas, but when I add OIII and SII--those areas lose the fainter structure.  Its almost as if the OIII or SII replaces the Ha in those areas, or somehow interferes with it.  Its hard to explain.  Maybe that was a Baader thing.  

[Rodd]

1 hour ago, PatrickGilliland said:

Hmmm - not sure - for some areas you will def want for others not so much.  HDR combo with some shorter images for bubble and the protostar would work well.  You could try 15x60 for that detail should all balance out nicely then.

Paddy

Starting over is a tough sell!  I am not familiar enough with mosaics to know if I can just add subs after the fact.  probably not as you can't do that with a normal image.  I would have to start from the beginning.  I guess that's not such big deal after all as I still have to do the OIII and SII, so redoing the Ha with new data won't be that bad, now that I know the process.  

[johnrt]

1 hour ago, Rodd said:

Thanks John--maybe to minimal?  There seems to be a saturation issue that I am trying to understand that must be fixed with more processing.  

No not more processing, just more careful stretching! Are you stretching with curves or just using the Histogram Transformation tool to stretch? I would not recommend the histogram transform, always stretch with curves and then just use the histogram tool to bring the black point back in. Curves gives you much better control over the contrast and white point as you reveal the detail in low signal areas.

Please **NEVER** transfer the result of the screen transfer tool to the histogram for your stretching!!

Edited August 29, 2016 by johnrt

[Rodd]

38 minutes ago, johnrt said:

No not more processing, just more careful stretching! Are you stretching with curves or just using the Histogram Transformation tool to stretch? I would not recommend the histogram transform, always stretch with curves and then just use the histogram tool to bring the black point back in. Curves gives you much better control over the contrast and white point as you reveal the detail in low signal areas.

Please **NEVER** transfer the result of the screen transfer tool to the histogram for your stretching!!

I tried using curves once to stretch--but then I could not figure out how to transfer the curves stretch to the Histogram to make it permanent.  How is that done?

[ollypenrice]

51 minutes ago, johnrt said:

No not more processing, just more careful stretching! Are you stretching with curves or just using the Histogram Transformation tool to stretch? I would not recommend the histogram transform, always stretch with curves and then just use the histogram tool to bring the black point back in. Curves gives you much better control over the contrast and white point as you reveal the detail in low signal areas.

Please **NEVER** transfer the result of the screen transfer tool to the histogram for your stretching!!

I couldn't possibly agree more. Shaping your own curve for a particular purpose and layering it sweetly into what you already have is so nice.

Olly

[johnrt]

48 minutes ago, Rodd said:

I tried using curves once to stretch--but then I could not figure out how to transfer the curves stretch to the Histogram to make it permanent.  How is that done?

It works the same as most other tools in PI, drag the apply triangle on to the image to apply the process, here's a screen shot from my Mac, it should look very similar if not the same on a PC.

[johnrt]

When stretching a mono Ha image it is best to start out with a very aggressive curve stretch (example below), using the Histo Transform to adjust the black point back between stretches, it can take a couple of these aggressive stretches depending on the brightness of the object. Then much more subtle stretches follow, being careful to watch the stars / background noise etc as you go. You can finish up with some S shaped curves to enhance contrast, but as always side with the light touch, not the PI hammer

 

Edited August 29, 2016 by johnrt

[Rodd]

18 minutes ago, johnrt said:

When stretching a mono Ha image it is best to start out with a very aggressive curve stretch (example below), using the Histo Transform to adjust the black point back between stretches, it can take a couple of these aggressive stretches depending on the brightness of the object. Then much more subtle stretches follow, being careful to watch the stars / background noise etc as you go. You can finish up with some S shaped curves to enhance contrast, but as always side with the light touch, not the PI hammer

 

I understand how to use curves--on non linear images. -I don't understand how to make it permanent (non linear) on a linear image.  Are you saying that if I open the stack, stretch it with the curves and then open the Histogram tool and chose the stack as my image view, the changes I make with the curves tool will show up on the histogram?  So any manipulation I make with the Curves tool is defacto permanent on a linear image?

[johnrt]

3 minutes ago, Rodd said:

I understand how to use curves--on non linear images. -I don't understand how to make it permanent (non linear) on a linear image.  Are you saying that if I open the stack, stretch it with the curves and then open the Histogram tool and chose the stack as my image view, the changes I make with the curves tool will show up on the histogram?  So any manipulation I make with the Curves tool is defacto permanent on a linear image?

Erm yes, I think, your PI talk is a little confusing, but basically the curves tool does the same thing as the histo transform tool but with much better control, changes are permanent.

Edited August 29, 2016 by johnrt

[Rodd]

1 hour ago, ollypenrice said:

I couldn't possibly agree more. Shaping your own curve for a particular purpose and layering it sweetly into what you already have is so nice.

Olly

One thing I have noted is that the STF never clips either high or low.  When ever I try to improve on teh STF I inariably clip--granted not that much (100 pixels maybe at most).  I guess I have to buckle down and learn how to use curves the right way.  But Curves transformation on linear images are not permanent until they are transferred to the Histogram--which is what I do not know how to do.  

[johnrt]

3 minutes ago, Rodd said:

But Curves transformation on linear images are not permanent until they are transferred to the Histogram--which is what I do not know how to do.  

Not sure what you are meaning here, they are, if you apply the curves process to the image as I indicated above. Drag the little triangle on to the image window.

[Rodd]

6 minutes ago, johnrt said:

Not sure what you are meaning here, they are, if you apply the curves process to the image as I indicated above. Drag the little triangle on to the image window.

Or you can click the blue square.  Here is what I mean.  When I tried to stretch the image with Curves (linear image) and saved it so that I could open it later to work on--none of the stretching I did in Curves Transformation tool was saved.  It was like the STF--for visual use but not permanent until you transfer it to the Histogram.

[johnrt]

1 hour ago, Rodd said:

Or you can click the blue square.  Here is what I mean.  When I tried to stretch the image with Curves (linear image) and saved it so that I could open it later to work on--none of the stretching I did in Curves Transformation tool was saved.  It was like the STF--for visual use but not permanent until you transfer it to the Histogram.

Not sure what you did wrong then Rodd, it has been permanent on every image I have ever used it on, maybe you just forgot to save it? The only tool that doesn't change the image and is for screen viewing purposes only in PI that I know of is the STF.

[Rodd]

On 8/28/2016 at 16:17, Barry-Wilson said:

This image really shows your progress Rodd - a great mosaic mono with good composition.

Strong signal features in the image maybe highlighted and saturated a tad too much, nevertheless a good image.

 

23 hours ago, johnrt said:

Not sure what you did wrong then Rodd, it has been permanent on every image I have ever used it on, maybe you just forgot to save it? The only tool that doesn't change the image and is for screen viewing purposes only in PI that I know of is the STF.

 

On 8/29/2016 at 06:02, PatrickGilliland said:

Now thats a super field of view - a little work on the saturation will help as Barry said but that has the makings of a real cracker.

Paddy

 

On 8/29/2016 at 07:56, johnrt said:

When you have enough good data to work work with, in terms of processing less is certainly more. Great mono image there Rodd.

 

On 8/29/2016 at 12:17, ollypenrice said:

Another super result to confirm your stunning progress, Rodd. This is great. I think that the Astrodon 3 is a self-processing filter. All the things you do in terms of contrast boosting, sharpening and star reduction just come straight off the filter!

Olly

Thanks guys--Here is the final stand alone Ha mosaic--I took Barry's advice to heart and I will not forget it for future images--wow--I am still amazed at the detail a 4" scope can capture.  Next step--reduce noise to nothing!