We are proposing some changes to the schema that could use another round of review and comments before the release of ACES v1.2. The goal with these changes was to help simplify implementation and address interoperability concerns raised about custom working spaces.
The changes can be found here and summarized below:
LMTs must apply in ACES (2065-1). This keeps LMTs more ‘universal’ and increases the chances of interoperability across software. It also keeps them in line with the LMT spec. We believe there is more work to be done here: to educate the industry on LMTs, refresh the 2014 spec, and create tools for users to make them (LMT working group?). What we wanted to avoid was a wild west of LMTs floating around with unknown input/output spaces, which is not much better than what happens today in a non-ACES workflow. With this change, advanced users could still make LMTs that internally go from ACES to another working space to perform an operation and go back to ACES.
CDLs can still apply in a custom working space. This means that more advanced workflows can still utilize CDL in a non-ACES working space for ‘knob turning’ such as those included as ACEScsc color spaces included here.
We felt this was a good compromise for the current AMF spec and the release of ACES v1.2. It is possible that new working spaces are introduced (or deprecated) by the time ACES v2.0 is released, and AMF could be revised at that time if necessary.
Please let us know your thoughts!