Computer Color is Broken
Why Hacker News recommends it
HN cites it as the accessible go-to explanation of gamma and color blending errors in image programs.
What it is
MinutePhysics explains that computers store brightness nonlinearly, so blurring and blending colors in raw RGB gives wrong, dark results. It shows why mixed colors, such as in gradients, look off.
Recommended by 4 HN commenters across 5 different months, 2015 to 2026.
What Hacker News said
Strong rec joedrago · 2026-06 · on “What every coder should know about Gamma Correction”
For those interested in this topic, I found minutephysics' treatment of this subject to be really pleasant and easy to grok. I had a talk I gave at work once or twice discussing color conversion and I would play a 90 second snippet from this (attributed appropriately) as it would very quickly crash course people on the reasoning behind an EOTF in a really cute and layman's terms kind of way: [this video]
Recommends mxfh · 2016-09 · on “What every coder should know about gamma”
Good reminder about these persisting blending issues in the linear interpretation of RGB values, which was well explained to non-coders as well here in a quite popular MinutePhysics video: [this video] As others commented the gamma scaling issues seem even more relevant. Just please, don't use RGB color space for generating gradients. In fact, it's ill fitted for most operations concerning the perception of colors as is. chroma.js : [LINK] D3 : [LINK] Interesting excursion: historically the default viewing gammas seem to have lowered, because broadcasting defaulted to dimly lit rooms, while today's ubiquitous displays are usually in brighter environments. [LINK]
Recommends quietbritishjim · 2020-02 · on “Brown: color is weird [video]”
If we're on the "watch this YouTube video if you work with colours" train, here's a great explanation of why gradients usually have a dark band in the middle, on the MinutePhysics channel: [this video] In short: the RBG values in an image are not actually the intensity of light, but some nonlinear function of intensity. To do a weighted average of two colours you need to first undo that nonlinearity, then do the averaging, then reapply the function. Most software doesn't do that so the colours end up wrong. This also applies to resizing images.
Recommends fireattack · 2021-01 · on “Ditherpunk: The article I wish I had about monochrome image dithering”
I misunderstood what you mean. Please ignore. On a side note, by colorspace I mainly meant that we can just stick with one with ultra-wide gamut. There are indeed other reasons to have different color spaces. (Below is my original comment for transparency.) ------------- Gamma isn't really about CRT; or I should say, they're two different things. The fact CRT has a somewhat physical "gamma" (light intensity varies nonlinearly with the voltage) is likely just a coincidence with the gamma we're talking here. The reason gamma is used in sRGB is because human eyes are more sensitive to changes in darker area, i.e. if the light intensity changes linearly, it feels more "jumpy" in darker end (whic
Recommends quietbritishjim · 2026-02 · on “Rendering the Visible Spectrum”
> The final piece of the puzzle is gamma correction. Applying gamma correction to these RGB coordinates produces a new set of values which we call (R', G', B') that are related to the original by a transfer function 6 ... The reason this is done is to account for how our eyes perceive brightness nonlinearly. We can distinguish changes in dark shades much more easily than light shades because a linear increase R in has much more of a relative effect when R is small. Switching to (R', G', B') therefore provides more resolution in dark regions of the image where the eye is more sensitive to variations in brightness. I'm surprised that this isn't mentioned much earlier and much more prominently.
Cites qwertyuiop924 · 2016-09 · on “What every coder should know about gamma”
I'd already seen most of this in a video (courtesy of Henry, aka MinutePhysics, [this video] ), but it was nice to see a programmer-oriented explanation, nonetheless.
Cites sometime · 2019-01 · on “Gamma error in picture scaling”
The same phenomenon also applies to color blending. In a modern context this phenomenon is especially visible in UI elements that blur the background: Up until recently many UIs did not get the blurring right, resulting in greyish dark spots between different colors. I think CSS blurring in most browsers still gets it wrong. [this video] (Computer Color is Broken, MinutePhysics)
Cites vanderZwan · 2019-04 · on “Unveiling the first-ever image of a black hole [video]”
Mind you, that's a JPG you are editing, so in the 8 bit sRGB color space. That means manipulations can lead to errors and illusions due to the color space being non-linear and clipped[0]. The original data was likely linear and at a much higher precision. If the source was a 16 bit linear grayscale PNG for example you could be much more assured you're not seeing the effects of JPG compression and things that were actually measured. EDIT: Found better sources: 16-bit sRGB PNG: [LINK] 180 MiB original TIFF: [LINK] [0] [this video]