100% stimulus is 10000 nits in HDR. That is why we setup the saturation sweeps at 50%.Thank you for your responses, and for the disc. I've been able to reproduce the situation using CalMAN and the VFPro, but that leads to additional questions on my part. Attached are two gamut measurement screenshots, both for P3D65|BT.2020 using the same metadata as on the disc, one with 25% sweeps at 50% stimulus, and one with 25% sweeps at 100% stimulus. (The version of CalMAN I'm using doesn't give the option for just 100% saturation for P3 for this page.) The 50% stimulus results are in line with my expectations, having taken similar measurements multiple times in the past. The 100% stimulus results were a surprise, however. The color patches that are displayed look the same as what I see with the disc, but CalMAN is telling me that what I see is largely what I should have in fact expected. The 100% measured values are certainly off from their reference points, with some consequently high dE's, but not half-a-gamut off. At 100% stimulus, the reference points (the small squares in the CIE chart) for 100% saturation P3 primaries have been pulled way in, such that red is pretty orange, green is basically yellow, and blue is pretty magenta. The screenshot has 100% green selected, and you can see by the zoom-in in the upper right of the CIE chart that the reference points for green and yellow are basically on top of each other. I assume this squishing is due to the volumetric shape of BT.2020? And also, when you say the P3 gamut patterns are at 100% stimulus, you mean 100% in BT.2020 terms, yes? So, does this clear anything up, or just add more confusion?
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