#131 NTSC filter "yellow boost" problem

[Anonymous]

The "yellow boost" option of the NTSC filter is using the actual NES palette index in its formula to calculate the output color. One effect of this is that when "yellow boost" is turned on, NES colors 0x20 and 0x30 look different from each other when PPU color emphasis bits are enabled. This is conceptually just wrong--the NTSC filter should only use the PPU output (luma and chroma) to determine the final display color.

[Nobody/Anonymous]

Probable proof of the fact that Nestopia is calculating off specific NES palette values instead of PPU output values is that if you play with the hue slider, you can see that some colors that would be yellow boosted by TVs - i.e. pink, red, orange, yellow, and some greens - no longer are yellow boosted as much or at all.