I've been use to so much information from the likes of Rob Gendler and some other notable PS users that their imaging steps are somewhat ingrained
There has been discussion on the whole subject of 2x2 binning and 1x1L + 2x2RGB combination methods on various forums - notably those whose members are still die-hard PS users. From what I can remember, one argument goes along the lines of "why go to all the expense of purchasing a high-quality, high-resolution CCD imager and then only use it at 'half' its capability?" Another argument is "Will the addition of an L-layer really enhance your RGB data in the first place, assuming that you didn't Bin the RGB data at the time of acquisition?"
The way I look at it is, if you have acquired the best data your imaging equipment can obtain, why would you have done this at anything OTHER than 1x1? OK, so if it takes 2 minutes for you to download your gazillion Mp images after each exposure, then that is just a limitation of your acquisition system. But, to have invested all that cash on your gear, and then to run it at 'half-capacity' because 'time is limited', then Ithink it might be time to re-think imaging strategies.
As Sander says, there are a whole load of statistical reasons for NOT dumping a Lum layer onto your RGB data - especially as high resolution RGB data actually already INCLUDES that Lum data in the first place. And, when you consider that you may already be fighting with three colour channels that may be producing different star sizes (due to, for example, differing 'bloat' caused by differing CCD sensitivity in each channel), then introducing a FOURTH channel, with yet another differing star size to contend with, will just seem to aggrevate the situation further, IMHO.
Sure, like others, I followed the LRGB 'mantra' preached by others, but soon realised that: with an OSC it was a complete waste of time; with an OSC and a Mono camera it just became altogether too difficult to be worthwhile; and with a Mono camera alone it just wasn't needed - not with the Power of PI and ACDNR to assist.
On that basis, my next camera will be a simple OSC device, and I have no intention of worrying about the Lu channel as PI simply extracts and processes the luminance data 'on the fly', whenever a process requires this to be done.
Even if I had the luxury of also upgrading my Mono imager, and I chose to get a full set of narrowband filters, I still don't see a situation where I would have to struggle with FOUR channels. And, I am certainly not going to have to worry about that any time soon - not unless my Lotto numbers come up
