Alternate method to performing HaR combinations - courtesy Don Goldman:
Create RGB and Ha Tiff files in Camera control software of choice i.e MaximDL, CCDSoft etc.
Process both in PS CS until about 80% finished
Split channels in the RGB
Layer Ha over R channel with normal mode and 30% opacity
Use HaR as red channel and combine RGB
Finish RGB processing
Finish Ha as Luminance
Saturate RGB by 30%
Paste in Luminance (Ha) using luminosity mode
Duplicate the RGB and use as top layer in soft light mode with 20% opacity
The above works quite well.
Noise invert mask "NIM" - courtesy ME
When close to the final steps of processing duplicate the flattened image
Create a layer mask on the duplicated image (reveal all)
Copy the original image
Click on the mask while holding the Alt key to fit the mask to screen
Paste the original image into the mask (it will turn grey - which is normal for masks)
Inverse the masked image ( the background turns white, while features grey or black)
Use levels on the mask to increase/decrease the mask size/impact.
Select the layer that has the mask applied
Apply a moderate to heavy noise reduction of your choice (X blur, dust&scratches, neat image, whatever)
If its too heavy, drop the opacity from 100% and/or duplicate the original layer again and use lighten mode to bring some stars back (if required).
NOTE: With the inverted mask anything that is black is not pushed through the noise reduction function. Use the levels slider wisely. You can also paint the mask to ensure certain areas i.e. details, stars, blah blah are masked as needed.
Flatten and enjoy. You don't have to wait until the end of the routine for this. It can be applied if you've got plenty of layers. Choice is yours.
That will be all for now. May provide more later.