Author Topic: About Hdri´s and corona tonemap control on/off  (Read 528 times)

2020-02-18, 17:51:09

arqrenderz

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Hi, i have a doubt, i was making some hdri library, and this struck my head, should we load hdris with corona tone map control and tonemaping disabled becouse otherwise we are affecting the hdri and clamping its values, i  use a tonemaping of 2 on almost all my images, when i put the tonemap off on the hdri the "intensity" of it its more real to what i see is the hdri, otherwise its way duller.
And if its not disabled are we making the highlight compression on the hdri twice?

Anyone with the knowledge out there to solve my doubt??
THX!

2020-02-19, 11:35:45
Reply #1

GeorgeK

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Hi, i have a doubt, i was making some hdri library, and this struck my head, should we load hdris with corona tone map control and tonemaping disabled becouse otherwise we are affecting the hdri and clamping its values, i  use a tonemaping of 2 on almost all my images, when i put the tonemap off on the hdri the "intensity" of it its more real to what i see is the hdri, otherwise its way duller.
And if its not disabled are we making the highlight compression on the hdri twice?

Anyone with the knowledge out there to solve my doubt??
THX!

Some visual examples of your issue would be welcome.
“Every artist was first an amateur”

2020-02-19, 12:13:05
Reply #2

Juraj

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This is some crazy level of overthinking :- ).

HDRi loaded as environment should absolutely not be loaded with tonemap control. You need the true linear unclamped values to light the scene, and these values shouldn't change between rendering restarts.

What you then visually see in Framebuffer is completely different thing. If you want different tonemapping for your environment and the rest of your image, then make a copy of your HDRi, place it into "Visible directly override" and then you can put tonemap control on it, together with CoronaColorCorrect to create your own tonemapping.

For most realistic approach, you wouldn't do that, the image and environments should tonemapped globally together in framebuffer. For creative approach, you can load absolutely anything in "Visible directly override", even tonemapped jpeg with -3 EV exposure correction to get that american look of blue sky visible from inside.
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2020-02-19, 19:48:28
Reply #3

arqrenderz

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HI, thx for the answers!
Here are the image comparisons, hdris are loaded as gamma 1.0, the only change is the corona tonemap control on/off
So my doubt comes from this behavior (hdri from hdri heaven)