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Please excuse my ignorance (still trying to wrap my head around this)

First off, I have watched BlenderGuru, CG Cookie and read the BSE threads from TROY_S and others, and followed this comical thread along with going down the "rabbit hole" . I feel I have an ok understanding of this, but certain statements really confuse me.

In this post,

enter image description here

the OP says he would not use tonemapping for exterior scenes and keep it Linear? Why not for exterior?

how would you render a scene and keep it Linear without tonemapping? Would this be done by selecting "none" in the filmic looks?

I thought if you are using "Filmic" from Troy_S you ARE tonemapping while keeping it linear?

... Sorry the more I learn the more confused I get.

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Filmic is both a tonemap and a 3D LUT for desaturation in its initial state. The key point is that Filmic operates on the View. That is, the reference remains scene referred linear, and the transform to view is strictly one-way, non-destructive. Even things such as the basic sRGB OETF or the more sophisticated Dolby PQ are in essence tone maps, as some tones are mapped to different encoded values. The line between a pure transfer function and tone map assignment can become quite blurry.

The reason you don't want to apply the tonemap or any nonlinear mangling inter-pipeline is that without a properly linearized reference space, almost every manipulation you perform on the data is broken. Blurs, smears, blends, overs, etc. are all broken if you disrupt the scene referred linear data by applying a nonlinear transform. Applying your aesthetic / encoding options strictly on the view gives you the best of all worlds.

There are a good number of other reasons that you would want to keep creative choices and such isolated to views and looks as well, but for the large part, the above is reason enough.

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  • $\begingroup$ If I understand correctly, this explains why tonemapping non-linear color spaces is not ideal, but doesn't have anything to do with OP's original question (tonemapping exterior scenes, as opposed to interior scenes). $\endgroup$ – Greg Zaal Apr 20 '17 at 11:58
  • $\begingroup$ If the data is going to be displayed on a display, it needs some degree of mapping of values. I strongly suspect that the original quote was how it happens; on the view or modifying linearised values to nonlinear. Former being ideal, latter being problematic. The quoted individual offered up an entirely questionable suggestion. $\endgroup$ – troy_s Apr 20 '17 at 13:54
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It's not.

Tonemapping is extremely common for exterior scenes, even outside the CG world. Before computers and exposure bracketing, photographers used graduated ND filters as a rudimentary way to tonemap the sky which is usually over-exposed compared to the rest of the landscape.

Tonemapping is an artistic choice, there are no rules for when you can and can't do it.

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  • $\begingroup$ The guy who wrote that (rawalanche) seemed to be a "professional". I am just curious to why he would say that? I feel like I am missing something. $\endgroup$ – icYou520 Mar 31 '17 at 18:12
  • $\begingroup$ and I did ask him but he hasn't responded, so that's why I am asking here. $\endgroup$ – icYou520 Mar 31 '17 at 18:18

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