Aces to rec709 (and vice versa) conversions and data colour preservation

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1

Sorry guys. It’s not another question about aces <> rec709 transforms and its issues. My ask is only about colour or data loss perspective. Are they that kind of conversions considered as “losless” ? or kind of lossy maybe?.

My idea was if rec709 it’s a much smaller colour space, the gamut is “cropped” destroying data colour, like resizing resolutions. That was clear for me, but today, after a long chat with some colleage, and reviewing some video , I’m not sure. Always considering the color transforms in 32bits ( 16bits should be enough? ) could we consider the way between aces to r709 like a two- way street to go and back between these colour spaces?

thanks

2

You lose info in the round trip conversion. (709>Aces>709) In my opinion, for tv spots, it doesn’t matter. Whenever I do a visual blur (rather then just a touch of blur on a matte, or something to take the edge of a phone graphic) I do the round trip with no problems.

3

No.

It’s a one-way street. Log files can go back and forth with linear ones without meaningful damage, but display colorspaces are all end-of-the-line.

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4

Like @ytf I do it all the time because I have to.

It is lossy so you do need to be mindful of this but sometime I need to be in a linear colourspace.

Grade at the end peeps :pray:

5

Ok , thanks. My concern was precisely “big” workflows, or general procedures to interchanges among rooms . Good to know.