Why exactly shouldn't we use Output - sRGB for converting linear sRGB textures?

I’ve read that it’s destructive, but haven’t really seen how in practice. I understand that Utility - sRGB - Texture is the way to go, but people tend to like to use Output - sRGB because it matches what they would see in a standard linear sRGB output, like “Photos” on Windows. I’d like to have a better understanding of exactly why we should not be taking that approach, but haven’t been able to find anything that explains it.

Are there any examples anyone can give or anything I can read to help get my head around it?

Hey @shanesimmsart,

So, let’s say I found that reference photo online and I would like to use for texturing or anything relevant in a Scene-Referred workflow:

This Output-Referred image has been rendered in a way or another to be pleasing on a particular display, e.g. S-Curve, contrast, saturation tweaks, you name it.

Now, and keeping in mind that the bottom left swatch (White 9.5 (.05 D)) reflectance should be around 91% , if I use the Output - sRGB as input transform to linearise the image, i.e. put it in Scene-Referred state, this swatch that was around 93% is now jumping to around 320% reflectance!

Because anyone paying attention to details will tell me that I should make sure that the Neutral 5 (.70 D) swatch (third from the bottom right) stays around 19%, I thus expose down the image accordingly:

What we see here is that the White 9.5 (.05 D) swatch is still well above 100%, i.e. 120%, and that the blacks are completely crushed.

At this point it is pretty much game over. You will need to massage your imagery until you find a sweet spot where it feels right and usable.

Hope that helps,

Cheers,

Thomas

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Thanks a lot Thomas, this seems obvious to me now!

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