how to go trans-parent, -lucent?

is the only way to make a vray material transparent is to enable refraction? that would mean, no simple and fast standard transparency
like max material.
when it comes to tranlucency, i am lost! when enabling “tranlucent”
the material renders black as black can be. (like matte material)
i change any different options and parameters, but it always renders BLACK.

what can i do?

thanks[/img]

re

Assign it to a material now…once you render it will be transparent.

i edited my original message: i want to say the material RENDERS black.
is there some one who can post a sample of a translucent material, please? i am not able to make one.

thanks,
james

Hi Shaggray,

I’ve put up an absorption tutorial in the tutorial section. This may answer some of your questions.

http://www.richardrosenman.com/vray\_absorption.htm

-Richard

hi richard,

thanks a lot for your immediate help. this answers some of my questions,
in deed. the question that remains is about translucency. how to achieve SSS-effects? what parameters are crucial. any material sample, translucency included would be a big help!

thanks

thx 4 the tut Richard.
But i got error message evrytime i open ur scene file (both) and max crashes.

“Runtime error : Out of scripter memory - use option to increase”

try to merge

merging leads to the same error…

To fix the crashing goto Max preferences, then MAXScript tab, In the memory area increase the initial memory heap used.

Has anyone else experience these errors? Please let me know so I can fix this as soon as possible. Thanks.

-Richard

so what is “translucency” good for

hi richard,

as it looks like, you can achieve stunning translucent effects without real “translucency”.

but this only works when you have the white glowing panels behind the object. then, it looks like as the light would be scattered inside the object. when i take the lightpanels away and put a lightsource somewhere outside the frame (venus pictures), the objects stay black because there is nothing visible to refract…i can`t find a connection between the absorbtion tutorial and the venus pictures. what`s the difference?

thanks,
james

Read carefully this tutorial from vlado itself:

http://www.vrayrender.com/stuff/MtlTutorial/

i followed the tutorial with the downloaded files. when it comes to switching on “tranlucent” the teapot renders BLACK. i turned the different parameters up and down, but it stays black…
what am i doing wrong?

I seemed to remember that there was a missing step in the translucency tutorial, which was discussed later in another thread. Does thing ring a bell to anyone?

-Richard

Hi richard!

Thanks for your tutorial.

A few questions though:
1) I’m a bit confused about translucency now. Why would we ever use this function if we can create similar effects using only absorbtion? Is the only difference when you check the translucency box, that light would travel a bit further because interior light distribution is calculated also?

2) What about the double sided option in the ‘options’ dialog of the material? Is this checked in your example, and in your venus materials?

3) In this image: http://www.richardrosenman.com/gallery/abs\_statue1.jpg
Is there a map in the refraction slot, or does it refract only the black environment? Does it also has a ior of 1.0?

4) is there a specific reason to use a darker color in the fog color compared to the diffuse? Or is this just coincidence?

Thanks for any info,

regards,

flipside

i also had my problems to understand the use of translucency, but what i found out is: the first green venus picture uses translucency the second doesn`t. the difference is: in the second pict, there are big white panels that are refracted through the statue. on the first picture is nothing to be refracted (black). “tranlucency” makes the light, that`s coming from somewhere outside the frame, bounce inside the statue. if you turned off "tranlucency the statue would be black and there wouldn`t be any
sss effect. that`s why richard says the “absorbtion is used to simulate translucency. unlike sub-surface-scattering…”
did you notice, that in every picture in the tutorial there are bright white objects behind or inside the translucent object. all the other pictures of the statue and the dragon (exept the one green statue with the white stripes behind it) are using “translucency”. like richard said, he missed to explain a little bit.
beside that, it`s an excellent tutorial!
thanks

Hey Guys.

To answer some of your questions:

First of all, I have not have much experience with Translucency so that’s why I haven’t included it in my tutorial - I don’t fully understand it, but from some of the tests I’ve done, I’ve basically produced the same renders I get with absorption, but brighter (almost self-illuminated) because the light is calculated bouncing inside. However, Vlado would certainly be a better person to expand on translucency rather than myself.

However, ALL the renders on my absorption page, the Venus ones, the statue ones, the dragon ones, NONE of them use translucency. All of these have been rendered with the translucency button UNCHECKED.

Some of you guys seems to be confused because the bright striped pannels are in some of the renders but not the others. This is because in these examples, I’m showing that you can produce absorption with light materials instead of lights. However, in all the renders such as the first Venus, the statue and the dragon, absorption is being accomplished through standard spotlights or light materials located from BEHIND the object. The importance of placing them behind the subject is crucial in order to see the absorption effect.

So to answer your questions, Flipside:

1. Again, I can’t really comment on what translucency does but to my knowledge, it will brighten up the object from the inside because of internally bounced light.

2.Double-Sided is UNCHECKED for ALL my absorption renders.

3. There is absolutely nothing in the refraction or environment slot. Once again, the absorption is produced through the use of backlit spotlights. The IOR, in most cases, has been set to 1.0, although it doesn’t have to be.

4.I find a darker fog color just makes the subject look ‘more dense’. If you increase the brighteness, the fog color is brighter and the subject also renders substantially brighter - I don’t find this to be a very realistic absorption effect, so I tend to keep my values lower.

Shaggray, I hope this clears some of your questions up - Translucency has NOT been used for ANY of my absorption renders.

If anyone has any tests they’d like to share about the use of translucency, I’d love to see them as well because as you guys can see, I also don’t know very much about it. :slight_smile:

Hope this helps, guys!

-Richard

Hi Richard, that clears up a lot, thanks!

I already did tests with translucency, but never came to any usefull conclusions…

Well, not much of an expert on this topic yet, but I have been playing around with Translucency and Absorption setups a bit tonight.

In particular, I’m interested in how they can be used to simulate realistic human flesh. One of the conclusions is that Translucency allows you to localize the effect by using a bitmap in Translucency slot. I find this very useful for characters, because I would like the translucent effect stronger at the base of the nose and on the rim of the ears than I would want on the forehead (where it is unlikely to occur).

I’ve gotten some reasonably acceptable results, but still not at the point where I am completely satisfied. If anyone has any experience or pointers on this topic, would love to hear.

transparency…

Wow, after reading this toruous series of threads, I have to ask myself why anyone, if just needing simple transparency, would bother perfecting what is obviously an arcane process, in order to set something up with a Vray material…

Why not just use a standard Max material? Just a single slider…

dave