RGB Imaging help

[JKB]

Well I am just about to go down the slippery slope of LRGB imaging but can anyone help or will I answer my question myself.

So I take lots of pics or video (depending on subject) using the 3 filters RGB and normal B&W for L? Stack each channel to make a single R,G,B and L image? Then do I just drop each into the relevant channel in Photoshop to create a colour image?

Hope that made sense?

Cheers Jamie

[Komet]

Thats about it in very basic terms. The L is added as a Luminosity layer over the top of the RGB.

[ollypenrice]

I use AstroArt, at the moment, to blend the three colour channels but I think PixInsight might be better. It is important to get them very accurately aligned before combining. I do a colour calibration in PI, though, as a half way house to using it exclusively. (I just haven't ploughed through all the tutorials yet.)

There are various ways to add the L layer but the most obvious in Ps is to paste it onto the RGB and use Blend Mode Luminance in Layers. Try it at 100% at first and then adjust the colour layer in Curves and in Saturation before settling on a final level of L for the flattened image.

Another way is to put the RGB into LAB mode, split channels, merge channels, but replace the original L channel of the RGB with the new Lum you have prepared.

BTW, I process the L and RGB before combining.

Olly

[dmahon]

If you use DSS to stack, upload all the LRGB images and just tick the ones for L,R,G,B seperately, basically doing four runs of stacking - but the clever bit is that you can right click on one of the images, probably the best L image, and select it as the "reference frame". Even when it is unticked during the RGB runs it is still used as the reference frame. Then they will be perfectly aligned and ready to just combine in photoshop.