The ffmpeg wiki page for H.264 states that:
Consider 18 (CRF) to be visually lossless or nearly so: it should look the same or nearly the same as the input but it isn't technically lossless.
Although, while I understand that H.265 is a relatively new codec, are there any general recommended settings to achieve a "visually lossless" encoding using X264 with ffmpeg?
The H.265 wiki page does state:
The CRF of 28 should visually correspond to libx264 video at CRF 23, but result in about half the file size.
But from what I've picked up, this scale of equivalents is not the same.
Edit regarding the duplicated question I am aware of the linked question, however 'visually lossless' strikes me as more of quite a specific thing - i.e. the point where specifying higher quality does not change the final image.
The linked question is asking about equivalent CRF levels to achieve equivalent quality. Although as I've just said, visually lossless would appear to me to be something much more specific than asking 'the equivalent of CRF 18'...