Synthetic Lums - One more time please

[jkmorse]

 
 
Ok, I am still trying to get my head around using unbinned RGB's and creating a synlum from them.  But that raises two questions:

First, exactly when in the workflow should you create the synlum?  It seems are two possibilities, (i) combining the "raw" RGB stacks WITHOUT performing DBE, background neutralization and color calibration to keep the RGB image "pure", or (ii) develop the RGBs normally, including performing DBE on each channel, then doing background neutralization and color calibration before creating the synlum so that the data for the synlum has been "cleaned up" first. 

Second, does this same theory apply to NB imaging under PI, namely, should I be creating a synlum from the combined Ha, OIII, and SII image.  Just shot new NB stacks of the Helix and NGC 7380 over the weekend.  I'm anxious do my first PI NB processing and want to get this right.

These are pretty basic questions, but I am new both to PI and the whole LRGB vs. synlum debate. 

Thanks,

Jim

[jkmorse]

 

Sorry folks, need to clarify that I do understand that Juan suggests using the ImageIntegration Tool to build the synlum which suggests that the only question for my first question below is whether to do DBE for each channel stack before creating the synlum.

Hope that clarifies.

Jim

[pfile]

talking thru my hat, but i suppose that DBE before or after is fine. however, the gradients in the synthetic lum made from non-DBE subs could conceivably be more complex and more difficult to remove after the fact.

as for NB, i don't see why not. if the "lum" image captures all the information in the filtered subs, it should work fine as a lum layer.

rob

[RickS]

I just built a synthetic Lum for M16 from Ha, OIII, SII, R, G and B and it worked quite nicely!

[jkmorse]

Thanks guys!

Jim