@Cyber just tested it over Parsec which uses a less agressive 4:2:2 chroma subsampling and as expected it destroys the image just as before. So to explain why this will be effecting the Sony Megatron more than other shaders:
First what is 4:2:0 chroma sub-sampling doing? If you look at this image from RTings you can clearly see:
Its halving the images colour resolution or in other terms removing 75% of the colour information. Removing 75% of anything is going to have an impact but its even more so with high frequency patterns that the megatron uses. What are high frequency patterns? Basically any pattern that rapidly changes across an image or to put in other terms a pattern that goes from one extreme to another over a pixel or two - a 2 pixel alternating black and white line pattern being a classical high frequency pattern.
So imagine you got the black white alternating pattern and instead of using black and white you used red, green and blue instead to create a 3 pixel RGB alternating pattern. Then image you use 4:2:0 chroma subsampling on it or in other words throw away 75% of the colour information. In vertical direction you’re actually going to be alright (because there is no high frequency pattern in that direction) but in the horizontal direction your RGB pattern now becomes RRB or GGB etc but with luminance preserved.
This is what is happening to the Sony Megatron.
The other shaders will exhibit the same behaviours if they use 100% masks. I suspect in your case they’re not using 100% masks and so the mask is taking up the colour of the pixel either side or whatever the algorithm does and so lowering the frequency of the pattern. Some kind of blooming, blurring etc will also have a similar effect by transfering colour information across pixels and so lowering the pattern frequency. Lower frequency patterns get hit much less by chroma sub-sampling/dropping resolution.
The final thing I’ll say is if you take a look at the RTings page below and look at the three test images under the title “When does it matter?”. Notice how the blue on red text and vice versa are greatly impacted but the white on black much less so? Thats because the white/black pixels are all about luminance which is preserved where as red, blue is more about colour.
What I will say is that you really shouldn’t do any detailed sub pixel work using chroma subsampling its just not going to work well.
I’ll start putting penny’s in the jar.
Reminds me of my buddy’s old HD Wega.
