Incredibly dark videos

[Peter]

The difference is chroma resolution and how it stores colour channels*.

Without lossless color ticked you get a video encoded in yuvj420p (or whetever your program calls it, this is FFMPEG's term).

With lossless color ticked you get a video encoded in bgr24.

The reason one may not exhibit the same darkness problem than the other is mostly incidental.

It depends on the program reading the file. A program that doesn't get one of them right (i.e. Pick up that it has 0-255 levels), may well get the other one right, but they're both 0-255 levels of brightness pixel formats, and they're both susceptible to being confused as a 16-235 levels of brightness pixel format.

*Without getting really technical yuv doesn't store a frame as red, green, and blue channel, instead using an alternative of storing a luma (brightness - i.e. Grey-scale) and two chroma (colour) channels, this can represent exactly the same information as red, green, blue, but has a big advantage - when we send a lower resolution chroma channel in YUV (this is chroma subsampling), it is way less noticeable than sending a lower resolution red, green, or blue channel. 420 is a ratio (4:2:0) describing a way the chromas are sampled in comparison to luma, this particular one holding quarter the resolution of colour in comparison to luma. Generally a person can only tell the difference on zoomed stills. The 'lossless color' option in FRAPs refers to chroma subsampling, not compression of colour, and not the codec as a whole (which is why it's an option for the colorspace of the same codec). If YUV420 is good enough for blu-ray, then it's probably good enough for video game footage.