Uli Plank wrote:This depends, most of all, on your media. IMHO, if your media is fast enough, constant quality is the better option. But you need to be sure that even the most demanding scene will not cause dropouts. Now, what’s a demanding scene? It’s all about contrast and amount of fine detail. Contrary to popular belief, it’s not about motion, since BRAW is an I-frame codec. OK, to some degree motion blur will reduce detail, so if there’s any effect, it’ll rather reduce demands, other than for GOP codecs.
Now, contrast and detail are not only about scene, but lenses too. The 12K sensor is outresolving most but the very best lenses. So, if you don’t use very good glass at optimal aperture, you’ll be hard pressed to see a difference between 12K and 8K when downsampled to 4. I’d say, carefully testing it under different conditions with your own lenses is essential.
But also check John Brawley’s commentaries in this subforum, he is the authority on these cameras and spreading most valuable information.
Constant quality is variable bitrate encoding, and with wavelets, which I am virtually certain BRAW is, that although I-frame, it still considers motion as well as detail, just not motion in the sense of interframe GOPs, but intraframe motion within individual frames that looks for repeating patterns in the content, representing them mathematically. The wavelet transform breaks down the image into smaller pieces called sub-bands that can be compressed more efficiently than the entire image frame.
Anyway, for 12K and 8K I find Q5 is usually okay whereas Netflix says Q3, or 8:1 and 5:1 for CBR. Where I noticed a slight deficiency with Q5 was rare, but nevertheless could present as a loss of a minimal amount of fine detail within a flat, neutral colored wall or surface of low contrast approaching the clipping point from bright or sunlight, the gradation from shade to sun on a flat neutral surface, but not loss of fine detail within busy areas such as print patterns or foliage, wood, skin or clothing. In other words, not anywhere that it really matters.