Eric. Ive read the thread you posted, and it seems youve gone into it much more than I have. I dont need to as I will only use it for Astro pics.
From what Ive seen elsewhere, the UV/IR blocking filter fitted as a mod allows extended red (into IR) response and just cuts off the nasty curve spikes after that, which all affects AWB for daytime use. Thats why another front daylight filter is required to bring balance back to normal for terestial use. It seems you have discovered that already. The thread also discusses other issues Im not aware of, it seems really you are the IIS DSLR expert Eric
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