Author Topic: tree Translucency  (Read 19400 times)

2014-02-11, 06:09:54

Alex Abarca

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Anyone one have any ideas on how to make this look realistic. I used color correction in the translucency swatch I took the main bitmap and made orangey, then I instanced it in the refraction swatch.

2014-02-11, 06:12:21
Reply #1

Alex Abarca

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Here is more info

2014-02-11, 06:48:13
Reply #2

Alex Abarca

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2014-02-11, 10:39:59
Reply #3

Ludvik Koutny

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Mistakes you are doing:

1, Do not use refraction, use just translucency. Set refraction level to 0, and remove map from refraction slot. Only parameter you need to tweak is translucency fraction.

2, You use way too much saturated texture for leaves. It does not look like natural green, but like cartoon acid.

3, Use glossiness map instead of reflection map. And if you after all still decide to use reflection map too, then make sure reflection color texture is greyscale. Tree leaves are not metal material, so they do not tint their reflection.

Look here https://www.google.cz/search?q=tree+leaves&tbm=isch&tbo=u&source=univ&sa=X&ei=1u_5UonUA4rIhAfGxIHAAQ&ved=0CCsQsAQ&biw=1920&bih=1115 and you will notice tree laves are a lot less saturated

2014-02-12, 20:30:19
Reply #4

Alex Abarca

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I'll give it a try, thank you.

2014-02-14, 10:51:46
Reply #5

astudio

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It's look like leaves veins are in wrong direction

2014-02-14, 12:40:23
Reply #6

gracelorn

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Well spotted, astudio ;) Looks like the texture is flipped.

2014-02-14, 15:59:04
Reply #7

romullus

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I tweaked your material a little bit. Obviously there's a room forimprovement even more, but for now it should do.
Scene is there: https://saugykla.teo.lt/Shares/Home.aspx?ShareID=9159e741-d8d5-4587-be4e-6fe6bf619ae6
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2014-02-15, 01:35:31
Reply #8

Alex Abarca

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Well spotted, astudio ;) Looks like the texture is flipped.

True, I didnt notice. I have to look closer!


I tweaked your material a little bit. Obviously there's a room forimprovement even more, but for now it should do.
Scene is there: https://saugykla.teo.lt/Shares/Home.aspx?ShareID=9159e741-d8d5-4587-be4e-6fe6bf619ae6

That looks totally awsome Romullus! I am going to take a close look at your material slot.

Below are other tests that I been doing in regards to leaves and translucency. The bad thing is that I am testing with flat models (leaves), it would be nice to have concave leaves. But in these examples I managed to get just a tad of translucency and warmer colors where light seems to pass. Please feel free to crit. Oh and sorry for the bad renders, I have a slow machine, but I rendered regions in places that are of interest.
« Last Edit: 2014-02-15, 01:51:06 by Alex Abarca »

2014-02-15, 10:30:21
Reply #9

maru

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I think leaves should have more "juicy" yellowish colour where the light is passing through. Some more reflectivity and a subtle bump map could also help. All these things are probably dependant on the kind of plant you are referring to. :) And yes, better geometry (for example leaves bending in some direction) would be nice.

Here are some examples:







2014-02-16, 11:41:55
Reply #10

vkiuru

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I think it's a mistake to tweak such materials in HDR lighting and/or taking closeup renders. Most of the time, at least in archviz, vegetation is going to be in the background and as such should look convincing when scattered across a wide area and should work with the most simple lighting.

Threads on this subject usually have a trend of showing off nice closeup shots of leaves lit with nice HDR lighting which IMO begs the question, are you actually tweaking a material or just showing off something that works in strictly controlled environment? Also it's extremely easy to get a material to look organic when you use an overcast lighting, but as soon as you introduce bright sunlight to the equation such materials oftentimes break down. My suggestion is to show how your material works in both overcast and sunlit conditions when doing these tests.

2014-02-17, 01:34:16
Reply #11

Alex Abarca

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I think leaves should have more "juicy" yellowish colour where the light is passing through. Some more reflectivity and a subtle bump map could also help. All these things are probably dependant on the kind of plant you are referring to. :) And yes, better geometry (for example leaves bending in some direction) would be nice.

Here are some examples:




Is corona capable of doing this?

2014-02-17, 01:42:32
Reply #12

Alex Abarca

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I think it's a mistake to tweak such materials in HDR lighting and/or taking closeup renders. Most of the time, at least in archviz, vegetation is going to be in the background and as such should look convincing when scattered across a wide area and should work with the most simple lighting.

Threads on this subject usually have a trend of showing off nice closeup shots of leaves lit with nice HDR lighting which IMO begs the question, are you actually tweaking a material or just showing off something that works in strictly controlled environment? Also it's extremely easy to get a material to look organic when you use an overcast lighting, but as soon as you introduce bright sunlight to the equation such materials oftentimes break down. My suggestion is to show how your material works in both overcast and sunlit conditions when doing these tests.

I agree with you, I think it also has alot to do with your HDRI exposure you decide to use. With some of them (that don't work) I do get out of whack colors. With the VIZpeople HDRI there is minimal differences in color varience. Color correction (map) is a key controller to have, because you can de-saturate as needed depending on the scene. But I totally agree with you, direct sun light is probably the best solution for making materials. The translucency will be the same in both scenarios, its just the color one has to watch out for. Here is a render from the tree without the HDRI.

Can anybody share their material composition for leaves/plants?...Thanks!

2014-02-17, 08:12:58
Reply #13

Ondra

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Is corona capable of doing this?

Yes, see the gallery on homepage
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2014-02-17, 12:56:45
Reply #14

maru

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Ok, here's my try. Maybe the translucency is a bit too exaggerated and leaves could be more reflective but it's because I've been looking at it for too long. :)