Official Discussion: Upcoming Hotfix Announcement

[CptLucky8]

@Bishop398

The cloud shader changes introduced in SU5 to attempt to increase their realism under certain lighting conditions are being reverted. This will prevent excess light from transmitting through them, distorting the overall scene exposure level. This will also make them look like they did prior to SU5.

-Matt | Working Title

@Bishop398

But, now that there has been time over the past week or two to observe these changes over a much wider range of machines than were even available during the beta flighting, it was agreed that the previous shader produces better results in more conditions.

I honestly think the new shader code is much better representing what you’d observe with a n.aked eye IRL, when the sun shinning through is making it nearly impossible to discerning details in the clouds because they are too bright for your eyes.

However the drawback in the implementation like you’re explaining is the global increase of what could be simply described as “ambiant” lighting, therefore reducing or eliminating some shadows, giving what some are also calling a “cartoon” look, etc… I’ve been also wondering whether another factor isn’t contributing to amplifying the differences (Rec.2020 vs BT.709 - see below).

I just hope personally this won’t be reverted to SU4 levels but this will be kept to SU5 rendering with a better balance of ambient/direct and MIE/Raleigh as well (there is another topic about this and haze since SU5…) in order to keep the much more realistic (to me at least) visuals of the clouds and their natural high reflectivity which is blinding IRL.

The main drawback of the increased luminosity to me is not much the clouds themselves, but the metering which is over exposing based on the total render average luma:

This is a problem in 2D and it is even more a problem in VR. This is why I’ve suggested the implementation of a spot metering or a weighted average system instead. Preliminary tests using the SteamVR FOV adjustment is showing me better results in averaging luma on the center quartile of the image (FOV 50%):

[BUG/FEATURE] Implement a metering system better suited for VR

Having said this and to keep things in balance, keeping the higher reflectivity would also require implementing this feature in my opinion:

[FEATURE REQUEST] Can you please add a “Sun Glasses” mode ? (not a joke)

TL;DR: if you’ve already tried looking to the sun in game through a sun visor in an aircraft, the suggestion is to make is a standard option you can toggle with the same rendering principle as the sun visor but in front of the camera eye(s). This works great as-is with the game renderer, nothing complex to add than a follow-the-camera 3D glass material in front.

Hope this helps!

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@CptLucky8

The difference to me with the exposition problem, before and after SU5, is that the game seems to be "tuned” for Xbox + HDR TV display. Not only many PC + monitor users don’t have HDR capable display devices, but the monitor and the TV might not be using the same gamma either. In addition, PC+monitors are calibrated for sRGB whereas HDR TV are calibrated for a wider color gamut.

Some good starting points:

“While the Rec. 2020 transfer function can be used for encoding, it is expected that most productions will use a reference monitor that has an appearance of using equivalent of gamma 2.4 transfer function”
Rec. 2020 - Wikipedia

“SDR for HD video uses a system chromaticity (chromaticity of color primaries and white point) specified in Rec. 709 (same as sRGB). […] HDR is commonly associated to a Wide Color Gamut (a system chromaticity wider than BT.709)”
HDR Chromacity

I haven’t done the maths, but your experience in lowering Gamma level to 0.7 seems to reflect the inverse of the change from 2.2 (sRGB) to 2.4 (HDTV).