Daily Builds 1.5

[agentdark45]

Interesting comparisons here. Could someone chime on whether the new CGX model with a super low glossy value would be better or more physically accurate way to simulate the light edges/ grazing angles of a fabric material vs the traditional diffuse falloff trick?

[Juraj]

No. Because you need control over the specular lobe size (gamma parameter in Trowbridge-Reitz version like Vray has) to do that.

Even then, I think it's poor solution, the sheen parameter seems to be doing something else (just classical fallof?).

I don't consider huge specular lobe and extreme rim grazing to be "physically accurate" fabric simulation. It just happens to look kind of similar. And sample like crap.

[karamox]

corona hihlight compression works weird. i did many tests to understand why in exterior scenes image is so dull. I can see where the render was done in corona and where in other renderer, because of the dullness of render. Not all people like dull images, clients like vivid images. Corona Hilghlict compress   does not work same as Reinhard, it works different. Ondra should either remake corona highlight compress , fix it so it does not become dull, to be as Reinhard or add Reinhard mapping type in addition to Filmic.

[zuliban]

 Reinhard is the worst thing one could want a render tone mapping ask for, just look at nuke ,arion fx, octane they have camera tone responses this is what corona should aim for , try to mimic real cameras or film . for example old films have very nice color tones  that now alot of digital photographers want to emulate and most of the renders images without post processing look gray , dull, lifeless this is why i think this is one of the most important features any render should aim for to become a real camera there should be no need for us to even use post production outside of renders.

[snakebox]

can someone please try to go from daily build 20th directly back to 1.4 stable?  run the installer and install over. 

I keep getting the errors mentioned earlier when I press render after installing 1.4.  I Basically can't roll back nor can I seem to fully uninstall corona and the beta build, what ever has changed.

[romullus]

No problems here whatsoever. Installed 1.4 after dailies, tried to render scene, that's "infested" with 1.5 features - everything is smooth and fine.

[vkiuru]

corona hihlight compression works weird. i did many tests to understand why in exterior scenes image is so dull. I can see where the render was done in corona and where in other renderer, because of the dullness of render. Not all people like dull images, clients like vivid images. Corona Hilghlict compress   does not work same as Reinhard, it works different. Ondra should either remake corona highlight compress , fix it so it does not become dull, to be as Reinhard or add Reinhard mapping type in addition to Filmic.

I don't think you know how and when to use the highlight compression. If your materials look dull when rendered you've got balancing issues elsewhere and reinhard is not a solution any more than Coronas highlight compression.

Or maybe I'm wrong in which case maybe show some examples. I always hated Vray reinhard.

[karamox]

corona highigt compress is not color map at all. i ended with that conclusion after many days of tests . it just compresses highlights as well as colors too. so no wonder why it looks dull. at low values result is acceptable. but in exterior you need to compress more, so result is uneacceptable, unless to use filmic color mapping. . it is interesting to hear Ondra opinion, how corona highlict compress works, is that color mapping at all... i wonder why he is ignoring that fact.
i wonder why you ar ehating reinhard, peter gutherie uses this method, do you think his works are bad. even vray exponential color maps that way it does not compresses color like corona does with highlight compress.

[Juraj]

Everyone should just use VFB+, it's miles ahead :- )

We need correct materials more.

Peter does use Reinhard, and then brings back some with s-curve. Filmic looks nicer from get-go.

[Ondra]

I dont unterstand you to be honest... What do you want to know? Highlight compression IS color mapping operator (but that does not mean anything by itself). It is implemented as reinhard mapping

i wonder why you ar ehating reinhard, peter gutherie uses this method, do you think his works are bad.

- just "what the fuck?"

[romullus]

There's a ton advanced tonemappers out there. If you want more control, save as linear and do tonemapping outside of renderer.

[Dom74]

yes, but it's more convenient to do some adjustements while rendering in 3DSMAX.

[Juraj]

Ok, I would like we get back to the discussion about mats :- ) There might be things missing here and there in Corona, but we really need correct PBR material. Even lowering IOR and intensity doesn't give correct result, bellow illustration shows why (you can have overbright grazing specular, yet dull front facing).

Here is Arnold alShader (it's open-source btw), where the difference is well-explained and illustrated.  http://blog.selfshadow.com/publications/s2014-shading-course/langlands/s2014_pbs_alshaders_slides.pdf

[zuliban]

Good that you bring this shader to the topic Juraj ,i Hope when Ondra develop the skin shader( my most wanted feature) , he study this Alasurface shader   ( http://www.anderslanglands.com/alshaders/alSurface.html ).
is the dream for any character artist that not use Arnold with all this energy conserving thing and advanced SSS.
There should be no energy loss from bump or angles and this happens in almost any modern render.

[plopalou]

Yeah! I would love to get my hands on a proper skin shader. I've used both Arnold and Vray and they both are really really good. You can even get acceptable results with the MR SSS shader if you know how to work with it.

CoronaSSS is actually pretty good, but there are a lot of things that I don't like. You can check my wip thread for my SSS tests.