Author Topic: Tonemapping - Plz Halp  (Read 53011 times)

2020-05-09, 18:10:43
Reply #315

Designerman77

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One more test I wanted to make.
This test isn't directly related to tone mapping, but I think that tone mapping is affected by it.


For this test I'm using path tracing for secondary bounces. The images have no saturation. I did try to match contrast and exposure slightly (without going crazy about it). No bloom, no DOF.
I notice a couple of things that I think are helping Fstorm almost unwantedly:

1- The energy of bounced light is much less in Fstorm. It makes it look more 3D-like, but it separates colors from surface to surface and adds deeper clarity to corners and small cracks or spaces.

I really wish there was a setting in corona to lower this energy that worked better than Max Sample Intensity. A while ago I started this thread about this issue: https://forum.corona-renderer.com/index.php?topic=23129.msg164407#msg164407

I also think this is the reason why nobody in this thread is talking about exterior renderings: because secondary bounces don't play such an important role in exteriors. If the issue with corona was exclusively tone mapping, why nobody is talking about exterior renderings?
Note: I don't think this is necessarily an issue. Corona looks great, but it seems that the trend in photos and renderings is this one: one where every surface is very separate from each other clearly.





2- Corona applies blur to all textures by default. Fstorm doesn't even have blur in their material AFAIK.
Why? Why blur by default?
The only reason I don't remove it is because Corona's bump mapping doesn't work without blur.




3- And one more thing. This is a question:
Does anyone know what this does exactly?




Nice observation!

2020-05-09, 18:35:32
Reply #316

romullus

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Your guess is correct, outside is a building with a wooden outer shell that reflects a lot of warm / orange light when it is indirectly lit by the sun.
However... from HDRs, which quite often have large areas with different colors, I do not consciously remember to have seen that effect.
I´ll keep an eye on it. :)

HDRI can't replace actually modeled 3D enviroment. It's simply impossible. HDRI is just mere approximation of complex light rays interaction with enviroment and some natural phenomena are impossible, or very hard to bake into 2 dimensional HDRI. If you want ultimate realism, you have to build full enviroment :]
I'm not Corona Team member. Everything i say, is my personal opinion only.
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2020-05-09, 18:55:50
Reply #317

Designerman77

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HDRI can't replace actually modeled 3D enviroment. It's simply impossible. HDRI is just mere approximation of complex light rays interaction with enviroment and some natural phenomena are impossible, or very hard to bake into 2 dimensional HDRI. If you want ultimate realism, you have to build full enviroment :]
[/quote]


Yep... looks like this. Thanks for specifically confirming it.
I guess then we have to place some orange & blue blocks in front of the windows sometimes... with "invisible to cam & reflections"-tag, so we get colored shadows. :)))

2020-05-09, 19:10:49
Reply #318

agentdark45

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3- And one more thing. This is a question:
Does anyone know what this does exactly?



Great test btw, the seperate surface effect is very noticable on the Fstorm renders especially in the corners.

The relative tickbox essentially changes the "max sample intensity" (as a comparison to Corona) per camera view/frame by detecting how bright light sources are. Its quite hit and miss so I usually untick it and keep the power to around 3-6 for frame lighting consistency.
Vray who?

2020-05-09, 22:58:11
Reply #319

cjwidd

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@lopaz Right, I see that now - I confused your post with another user. Sorry if you mentioned the exposure adjustment before, I might have missed it.

2020-05-10, 16:54:13
Reply #320

Designerman77

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So, dudes & devs:

thanks to a hint from our buddy CJWIDD, I switched to Dubcat´s ACES simulation HC 0.7, etc.
After tens of renders (interiors) in the last days, this will stay standard setting for me... despite the stronger burning in the highlights.

Renders (contrasts, gradients, etc.) look waaaay more photo-like and more natural to the eye with HC 0.7. Especially in small rooms with poor light sources, you get much more energy.
Details that looked totally washed out at HC 1 and above, suddenly appear and the lighting becomes natural and alive.

In my humble opinion, the base setting of the HC in Corona seems too high. That's why images always look rather washed out & grayish and one messes around with contrasts to compensate it - with the known side effects of color burning, etc.

HC lower than 1 as a standard and a better / stronger effect of filmic highlights, so one can reduce clipping to a natural degree when needed, would be perfect in Corona.

What do you guys think?

2020-05-10, 22:57:00
Reply #321

Jpjapers

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So, dudes & devs:

thanks to a hint from our buddy CJWIDD, I switched to Dubcat´s ACES simulation HC 0.7, etc.
After tens of renders (interiors) in the last days, this will stay standard setting for me... despite the stronger burning in the highlights.

Renders (contrasts, gradients, etc.) look waaaay more photo-like and more natural to the eye with HC 0.7. Especially in small rooms with poor light sources, you get much more energy.
Details that looked totally washed out at HC 1 and above, suddenly appear and the lighting becomes natural and alive.

In my humble opinion, the base setting of the HC in Corona seems too high. That's why images always look rather washed out & grayish and one messes around with contrasts to compensate it - with the known side effects of color burning, etc.

HC lower than 1 as a standard and a better / stronger effect of filmic highlights, so one can reduce clipping to a natural degree when needed, would be perfect in Corona.

What do you guys think?

0.7 has been my starting point for a long time though i sometimes take it up to Max 2.5 in some circumstances.

2020-05-10, 23:18:16
Reply #322

lupaz

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So, dudes & devs:

thanks to a hint from our buddy CJWIDD, I switched to Dubcat´s ACES simulation HC 0.7, etc.


Could you give all the settings and files (cube file?), if any? I'd like to make some tests and it'sa looong thread. Thanks.

2020-05-10, 23:37:24
Reply #323

Designerman77

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So, dudes & devs:

thanks to a hint from our buddy CJWIDD, I switched to Dubcat´s ACES simulation HC 0.7, etc.


Could you give all the settings and files (cube file?), if any? I'd like to make some tests and it'sa looong thread. Thanks.


Hey, thanks!

I´m in C4D, I guess you work in Max.
Here is a screenshot of my settings I use for rendering tens of these types of white rooms.
Not a project of high artistic value... The client needs them quick and quicker. :)))))

However, with HC 0.7 etc. one sees a huge difference.
HC 1.0 + looks way more dull, grayish, contrasts & transitions on walls are very clamped, less contact shadows in the edges & corners, etc.

2020-05-11, 02:44:48
Reply #324

PROH

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@lupaz - See post #229 for Dubcats settings.

2020-05-11, 04:21:03
Reply #325

lupaz

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@lupaz - See post #229 for Dubcats settings.

got it.
thanks man

2020-05-11, 07:32:52
Reply #326

cjwidd

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@Designerman77 looks pretty nice! The scene is lit with HDRI only or sun/sky with backplate?

2020-05-11, 09:46:24
Reply #327

Designerman77

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@Designerman77 looks pretty nice! The scene is lit with HDRI only or sun/sky with backplate?


Hey cjwidd... It is so funny how others see one´s renders... while I am mostly not satisfied with them.
Honestly, mostly because of that light / contrasts / colors - topic all of us discuss here. Especially in very white rooms with little contrasting furniture etc.
But thanks. :)

A simple HDR sky and a messy, low res backplate - because the client wants some green behind the window.
As mentioned... this specific job is not about perfection at all. Thanks God the rooms have to also be rendered with furniture. At least a bit of "art". :)


HDR is from "free HDR skies", number 129
I like that those guys make 360° HDRs, so you get natural lighting on your walls & ceiling from greenery in the HDR.

2020-05-11, 09:59:14
Reply #328

Designerman77

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A sub-topic that - in my opinion - is very important in this context, is the highlight compression. This would deserve a special attention from the devs.

From electronic music recording, some of you might know compression and... really great compression like for example that from UAD.
"Normal" audio compressors brutally cut away frequencies, leaving behind a dull and deaf sound without details.
A similar effect I see in digital picture compression.

Question: is it technically possible to program a HC that compresses while still leaving much details?
Or the same behavior for the Filmic Highlight - especially handy when using HC lower than 1.

At the moment, either you crank up the HC and land in a dull image, or you lower HC, get way nicer lighting but the Filmic Highlight has to be pushed up to brutal values as compensation,
so your highlight lose most details.

2020-05-11, 16:47:40
Reply #329

lupaz

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I've been using <1.0 HC, as is described in Dubcat's ACES emulation settings, and it *feels* like it brings back dynamic range, i.e. the image looks more punchy, more depth

I never tried those settings. I have to admit they sound completely nonsense for me, on paper at least. Maybe the combination with filmic highlight counterbalances the 0.7 HC compression. I'll give it a go tho, as Dubcat always conducted is tests rigorously and always delivered good stuff. Settings are attached for those wondering.

This is without any LUT?