Hi to all,
With this post I’m hoping that someone will be able to give me some simple insight into using ACES to produce different deliverables.
I’ll first establish a context: I’m grading a trailer in DCI-P3 in Resolve 12.5.5.
At the end of my session I decide to produce the 709 version by switching the ODT to 709. Online needs to have a 709 version quickly. Which is not our usual workflow. Normally, I would render to P3 and convert to 709 with a LUT after online. At the moment, it’s not possible to online and package in ACES within Resolve. Titles look awful, transitions and fades don’t behave properly etc…
I change rooms and look at my new version in 709. Looks pretty good, but I’m in a hurry. I don’t think much of it. A few weeks later I see the trailer on my computer and notice it looks a little bit washed out and dull. I get the same comment for the DP…
Yesterday I have a few minutes to look into this. So I go ahead a compare different P3 to 709 conversions. Honestly, I thought the going from P3 to 709 would be more seamless. But it’s not… It’s “very different”.
I’ve already had this discussion already by email with the ACES folks. From what I understood, a colorspace conversion LUT is a “straight up thing”. The ACES “conversion” is setup to have a intent. But what is the intent? What am I missing here that I don’t understand? Why are the images dull and flat? And why is the white point bluer?
The Rec709 (d60 dim.) looks a little bit better. It seems to have the correct WP. But still is flat and dull…
So please can someone explain simply (not science lingo) what we’re supposed to do with this? Are we supposed to adjust the grade? What is the intent that ACES but into this conversion? Is the fact that we calibrate our monitors to 2.2 the issue. Or, am I just not understanding what this is and what I’m supposed to do?
Cause from what I read ACES was supposed to be real simple. Need a 709 output? Just switch to 709…
Here are some examples:
Split screen…
On the left side: Grab from my ACES project. IDT applied is Rec709.
On the right side: Grab from a P3 render (from ACES) with a P3 to 709 LUT applied.
On the left side: Grab from my ACES project. IDT applied is Rec709 (D60 sim.)
On the right side: Grab from a P3 render (from ACES) with a P3 to 709 LUT applied.
As you can probably see. The WP is much closer to my original.
And I’ll also state that the P3-709 LUT is spot on.
Thanks for the input!