NES Colour: FAQ

What?

Why?

  • The more I learn about colour science in my work and in my hobbies, the more "by eye" colour matching and calibration always dissatisfies me, because your brain lies to you about colour.
  • I like measurements and numbers. I like colour science. I like old video games. This covers all three.
  • I am a terrible software developer (go on, laugh at the code I publish). But I love open source and video game preservation, so this is my small way of contributing back.

How?

  • Read the page titled Method.

What numbers on the 240p Test Suite do your measurements correspond to?

  • I measure 52 colours from 00 (top left) to 0C (top right), then continue 10-1C (second line), 20-2C (third line), 30-3C (fourth line).
  • Values roughly sweep across hues left to right, and increase in brightness top to bottom.

What colours does "Super Mario Bros." Title/World 1-1 use?

  • Sky: 22
  • Title box background: 17
  • Title box font: 36
  • Hedges: 29
  • Hills: 1A

What colours does "The Legend of Zelda" use?

  • Title screen background: 36
  • Title screen font: 17
  • Link's tunic: 29
  • Mountains in opening area: 1A
  • Background in opening area: 37

What is this Colour Science nonsense?

  • I made a boring video to explain it:

What is a colorimeter?

  • Specifically, a tristimulus colorimeter.
  • A device that objectively measures light wavelengths and amplitudes and reports them back to a computer.
  • It is very accurate for measuring colour specifically - several hundred times more than your eyes for a variety of reasons.
  • It's a bit rubbish at measuring very low light values, however even the NES's darkest colours don't fall into these problem areas.
  • Spectrometers (sometimes called spectrophotometers) are more accurate devices than colorimeters, but also cost 50-100 times as much for the given accuracy. As I am not a squintillionaire, I only have a colorimeter.

What is the dE / Delta E value you use?

  • We plot colours on a 3D graph as a way to represent them easily.
  • The Delta E is the measured error or difference between two colours, plotted on a 3D graph
  • It comes in three flavours:
    • CIE dE76 - standard euclidean distance, absolute
    • CIE dE94 - updated value with respect to perceptual uniformity
    • CIE dE2000 - updated once again with respect to perceptual uniformity
  • "Perceptual uniformity" gives a better indication of how sensitive the human brain is to colour differences at different frequencies
    • For example, you are far more sensitive to differences in blues than reds, and far less sensitive to differences in greens than anything else
    • See the MacAdam Elipses for a visual representation
  • If I refer to shorthand "dE", I mean dE2000.
  • A dE of 2.0 or lower is considered to be "not noticeable without close inspection", and the target dE of most professional display calibrators and production/TV/film/VFX studios.
  • A dE of 1.0 or lower is considered to be not noticeable at all.
  • Don't fall into the trap of obsessing that "dE 0.5 is better than dE 0.9". You honestly can't tell. Don't go all audiophile on me.

Why can't I just use my eyes?

Why do you render the values out 4 times?

  • Your brain lies to you about colour. Like, a lot.
  • You might even think that certain repeated colours look different sometimes. See? Your brain lied to you again. Check results with a colour picker tool.
  • The different backgrounds help your critical analysis
    • Black is better for darker colours
    • White is better for brighter colours
    • Greys help mid tones. Specifically, on an sRGB calibrated screen with a Gamma curve of 2.2, middle grey represents 50% "lightness".

Is this the new bible on NES colour?

  • No. This is merely a comparative measurement, with far too much variability to be considered that.
  • Luminance levels vary wildly between real NES hardware models, let alone FPGA systems and emulator/computer output, which likely affects these results. I do my best to minimise that impact (see the page titled Method).
  • Each display contains a chip that decodes composite video into useful information for the display (typically RGB). Different chips do slightly different things. I'll do my best to note the display make/model for each comparison I do.

Can your findings be used to make new "perfect" NES palettes?

  • No. These are relative measurements on a given display, and only valuable as a comparison between two colours.
  • There are much smarter people than I doing work on measuring NES video co-ordinates on vectorscopes measuring electrical signal outputs directly, as well as calculating internal NES voltages with respect to CMOS voltage curve characteristics. That work will yield much more objective results.
  • At best, these results I'm presenting can assist palette creators to see where they need to tweak values, but again this is relative to a given display.
  • At worst, this is all useless, and just a bit of fun for me.

Which NES colour palette is the best?

  • I'm not going to make that call, nor could I even if I wanted to.
  • I'll give numbers, stats and rendered comparisons, with the caveat that it's all relative to certain displays/chips, and you can make up your own mind.

This is stupid and your results don't change my mind on what I like.

  • That's not a question.
  • Play whatever like, however you like. There's no wrong way to play a video game IMHO.

You spell "color" weird.

  • Again, not a question.
  • It's English, from England. The language I speak.