Help with splitting R, G and B channels in Photoshop please

[michaelmorris]

I'm working my way through processing the DSLR image of the Rosette Nebula I took at SGL X.  I want to process the nebula separately from the surrounding stars using Starton software to separate the nebula.  My problem is that Straton only works on monochrome images.  I need to create three separate monochrome images from the 16 bit RGB TIFF file, one image for each colour channel..  Try as I might, I can't work out how to do this in Photoshop. 

Help!!!

[swag72]

Click on the channels tab and you will see all the coloured channels there. To the right of that menu is another drop down menu and if you click that you'll see 'split channels' - Hey presto!

[michaelmorris]

Thanks Sara

I've tried that but it seems to be greyed out.  I did get it to work if I converted the image to 32 bit, but I lost almost all the nebulosity in each resulting image.  I could stretch each image again to get it back, but a) it is a faff, and I then have to scale it back again afterwards if I convert it back to a 16 bit file.

Surely there is an easier way?

Is there an Action that does this?

[michaelmorris]

Just worked out how to do it.  If I save the file as a photoshop (.psd file) it works fine.

Thanks