I also saw it on 4chan first, a long time ago, but I&#x27;d bet this trick has been around for many years before that. The gamma of 0.023 also seems to have been the de-facto way to do this.<p>Here&#x27;s a good illustration that shows how the pixel values of the 2 images have been &quot;compressed&quot; into two separate ranges:<p><a href="https:&#x2F;&#x2F;archive.rebeccablacktech.com&#x2F;boards&#x2F;g&#x2F;img&#x2F;0244&#x2F;57&#x2F;1335397543121.jpg" rel="nofollow">https:&#x2F;&#x2F;archive.rebeccablacktech.com&#x2F;boards&#x2F;g&#x2F;img&#x2F;0244&#x2F;57&#x2F;13...</a>