IC1848

[astro mick]

Hi.

I think most of us got a good night on Monday,so decided to have ago at IC1848,also known as the Soul Nebulae in Cassiopia.  

This was taken with my ED80 and Atik 314L+ ccd camera.

It is a HaRGB image,where the Ha was added to the Red Channel at about 50% opacity.

I imaged for 2hrs per filter,and calibrated with Bias and Flats.

Not much green and blue could be stretched out the images,and I did,nt stretch the red channel at all,as I knew the Ha would tend to swamp things.

Anyway.

Cheers.

Mick.

 

 

Edited November 22, 2019 by astro mick

[MartinB]

The Ha colouration is excellent Mick but I wonder if some of the Ha data is being lost in the combining and processing.  Have you done an Ha mono process?  Obviously the challenge is to extract all the detail in the Ha without degrading the colour.  Did you use lighten as the blend mode for the Ha?  Also, did you create a luminence channel using a combination of HaRGB?  An Ha dominated luminence channel does tend to lead to the dreaded salmon coloured Ha but PS has ways of getting around this to some extent.

[astro mick]

Hi Martin.

Thanks.

Yes I did a full process of the Ha channel,but when added to the Red channel it just swamped it to overwhelming RED.No I did,nt change the blend mode to lighten.

As to the creating a Luminance form the HaRGB, I don't know how to.

Their is little info out there on how to process HaRGB.

If you know of some tips,please let me know.

Mick. 

Edited November 21, 2019 by astro mick

[MartinB]

1 hour ago, astro mick said:

Hi Martin.

Thanks.

Yes I did a full process of the Ha channel,but when added to the Red channel it just swamped it to overwhelming RED.No I did,nt change the blend mode to lighten.

As to the creating a Luminance form the HaRGB, I don't know how to.

Their is little info out there on how to process HaRGB.

If you know of some tips,please let me know.

Mick. 

It is probably better to add ha to the the red channel using lighten as the blend mode.  This will help preserve the red in your stars whilst allowing through the hydrogen alpha nebulosity.  Apart from the stars you can expect the red ha to dominate.  This is how it would look if we could see it up close.  There is some OIII in there but very little compared to the ha.

You create an HaRGB lum by blending the HaR  with the green and the blue again using lighten as the blend mode.  The 3 channels need to have a similar stretch.  It may be, on this target, that the g and b are adding no additional detail in which case stick with HaR.   The problem adding a luminance is that it will bleach your colour so you need to reduce the opacity and try to restore ha colour using tools such as selective colour.

Your image looks great but I am sure there more in there.

[astro mick]

22 hours ago, MartinB said:

It is probably better to add ha to the the red channel using lighten as the blend mode.  This will help preserve the red in your stars whilst allowing through the hydrogen alpha nebulosity.  Apart from the stars you can expect the red ha to dominate.  This is how it would look if we could see it up close.  There is some OIII in there but very little compared to the ha.

You create an HaRGB lum by blending the HaR  with the green and the blue again using lighten as the blend mode.  The 3 channels need to have a similar stretch.  It may be, on this target, that the g and b are adding no additional detail in which case stick with HaR.   The problem adding a luminance is that it will bleach your colour so you need to reduce the opacity and try to restore ha colour using tools such as selective colour.

Your image looks great but I am sure there more in there.

Thanks very Martin,some very useful advice.Much appreciated.

Mick.