Corona -> Cycles

Hi there.

I tried to recreate famous Johannes Lindqvist scene with Cycles.

This is the original rendered with Corona:

This is Cycles (Filmic, High Contrast):

And this is Cycles but Standard CM:

The scene is relatively close, but there are a lot of differences.
If we put Color Management aside, I am curious how can I improve lamp shader and is it possible to get that nice light splattering on wall?
Lamp is partly solid, partly thin so I mixed translucent with principled shader (95%-5%) which has volume scattering. Is it possible to achieve nicer light distribution without cheating and putting lamp outside?
Second part is metal. Corona can go higher with it’s specular value. Higher specular doesn’t help for metals in principled bsdf. I tried to put metalness to 2 or 3 but that lights the whole shader, not just the highlights so it’s not perfect.
And I noticed reflections on bottom marbel shader don’t have such crisp reflections. How to achieve that?

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Hello!! What version of blender did you use?

Blender version is 2.82.7

Lovely little project. Just curious if you tried to apply gradient for the lamp shader to control light emission?
Recently I was puzzled by difference of two rendered images. Two identical images with slightly different CM settings. The problem occurs when file is saved. With Standard enabled in CM settings saved image looks identical to render on Blender. While with Filmic setting enabled image looks all right in Blender but saved and viewed on Windows default photo viewer or Photoshop. Lights blown out of proportion. So I wonder how did you achieved this kind of consistency? Would you like to share you settings?

Thanks

I haven’t tried gradient map. Do you have idea how to approach this problem?
What would you exactly control with gradient map?

Regarding different CM-s for saved images, it sounds to me like you didn’t bake in Filmic Color Management upon saving. See your “Save as render” option is it ticked or not, and in what format have you saved?

I actually left the same strength for HDRI environment as it was in original file. Then I ramped up the blue component of the hdri to get that blueish color cast and at last in White Balance of Photographer addon I shifted color tint towards green so I would get rid of too much magenta color splashes.

I haven’t have opportunity yet to implement gradient technique but I will attach a screenshot form one tutorial. Basically it’s a chain of nodes. Take a look at this tutorial where guy briefly touches the subject from 1:57. https://www.youtube.com/watch?v=RVY31_odP4A&lc=z231sxcxmmnkdx10oacdp4304z0mmrz2s2ixj0nyq0xw03c010c

Thanks for the tip! For some reasons my “Save as render” was unchecked. There is one little thing that bothers me with my output I get Untagded colour profile. I wonder if you get the same?

gradient

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This is a good tip :+1: I have to test out how would pure translucent material react.

Can you explain in detail what do you mean by “Untaged” colour profile?
Where does it say that?

I gues it could be a solution although I never tried. If I had to achive light rim and scattering you looking for I would also try different light set ups and/or tricks inside the lamp shade that would capture diffuse and block some of it’s light and let some to escape at the bottom of the shade so you have light emitting as corona on the wall. Just an idea.

Normally images have colour profile assigned to them. Most commonly used colour profiles are: sRGB , AdobeRGB and Display P3. When I say untagged I mean Blender for some reason does not assign Colour profile when rendered. You can actually assign colour profile in Photoshop and other programs.
Have a look what it looks like!

Got it.
It probably assigns default sRGB profile, but it doesn’t have a code which writes color profile metadata to the image.

Actually, the light in Cycles casts that bottom light in uspide-down shape same as Corona. It’s much more pronounced when upper light isn’t coming trough. The problem with the light is if I turn it up there is a lot of light on the bottom coming through and it’s splashing all over the place. If I turn it down so bottom is perfect, upper light on the wall and on the lamp will be too weak. Like you said, best bet would be to change lamp shader so it would somehow amplify collected light and become more emissive. Come to think of it I could always try and mix emission shader into all of this!

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I also noticed that Corona render preserves lamp stand reflection in the window but the Blender. A small details but I like it. Anyway very realistic render yours.

Exactly! And also the reflections of light in metal are much stronger.

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Well, SDS & now even fast caustics, mem. efficient displacement… and then some, is where Cycles lacks. But nothing to worry about, since it has different focus, goal & target audience - so, just know your intent and you’ll have it easier to choose and master the tool :wink:

Can you share the blend considering the original requires paid software to convert

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Ok, at least now I know it is about features. :slight_smile:

There you go: https://drive.google.com/file/d/1kKrC2NSEbIAby1CP55iHbpXGdjOkPRFX/view?usp=sharing

Textures can be downloaded from the web.

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I got this after playing around for a bit

Sweetnes! We don’t need corona! :slight_smile:
Can you share what changes you have made?

All kinds of stuff lol don’t remember everything… Here is the blend though and I changed some more settings, Exaggerated the lamp a bit

http://pasteall.org/blend/index.php?id=53089

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Thank you! Helped me alot!

I couldn’t believe that window would look like this if it would be only visible to camera rays.
And that SSS on plant leaves. I thought we should only use translucency on thin models.

P.S. I see you removed light portal. So the portals became obsolete?

Portals are pretty useless when hey are large, SSS should work as long as it isnt random walk, You had sss on the lampshade I switched it to translucent, I think the biggest problem with the window was your exposure was wrong and the stuff outside was too bright to see the reflections

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Actually I changed everything like in your file, and the window settings were last.
So oddly enough that made the reflection pop the most. I was pretty puzzled by this myself.
Try it, maybe I’m mistaken.