Question about HaRGB mosaics

[Phil Leigh]

Hi,
I am in the midst of a multi-panel mosaic of the Heart and Soul nebulae. So far I have 4 connected RGB frames and will need a 5th & 6th.
I intend to augment the RGB frames with Ha.

My question is; what is the best assembly sequence or does it not matter? - should I create HaRGB panels and then union them OR do I create 2 complete mosiacs (RGB and Ha) then merge them?
thanks

Phil

[pfile]

probably more foolproof to stack up each frame into HaRGB and then do the mosaic merge.

in theory if you have a good reference image to register all the panes to, making a mosaic of each channel separately should come out okay. but there could be minute differences in the registration of each channel's mosaic, especially if there is enough distortion in each pane.

rob

[Phil Leigh]

Thanks Rob - that makes perfect sense!

[Tom OD]

So far I have 10 pane mosaic of LRGB by making an RGB layer and a separate L layer for each pane. It does work that way. I have not tried L, R,G, and B as a separate layer though. Seems both methods should work. You need good flat data, and equally good colour balance on the RGB frames though.
Tom