realVivek wrote:
CFA removal enhances the UV sensitivity by several stops, increases the visible sensitivity by 1~2 stops and reduces the IR sensitivity by at least one stop.
I could understand the CFA dyes being opaque to UV, but the rest doesn't make sense to me.
You would think the CFA cuts out 2/3rds of the incoming [visible] light but in practice the response of the dyes overlap so it's closer to 50% or 1 stop. However the CFA lies underneath the microlenses so in order to remove it you also end up removing the microleses, which reduces sensitivity. What I've read from other people who have removed the CFA/microlenses is that losing the microlenses undoes most of the advantage gained from not having a CFA so the improvement in sensitivity is slight.
With regards to IR sensitivity, it's not possible for the removal of a filter to increase sensitivity (except in the really weird case with multiple polarizers), which means the only possibility would be that microlenses are somehow several times more effective in IR than with visible light, which seems counterintuitive for something only designed to work in the visible spectrum.
Jan 12, 2021 at 04:51 PM
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