[tom]

A MIRROR OF THIS CHALLENGE ALSO APPEARS HERE:
http://forums.cgsociety.org/showthread. ... ge=1&pp=15

A few days ago, I've revisited H.Jensen's frosted glass dragon scene with Maxwell Render V2 and
it turned out pretty satisfying in terms of quality I've expected. As you see, the scene is very simple
and it's only demonstrating rough dielectrics. The subject is not very challenging for most of the biased engines
but, it could be a real pain when it comes to unbiased cores unless they are not properly optimized/implemented,
especially for interactive and realtime rendering as their BSDF and microsurface approach is playing a huge role.

Here's the original work done by Henrik Wann Jensen (2003):
http://graphics.ucsd.edu/~henrik/images/raytrace.html




Below is the frosted glass dragon rendered with Maxwell Render V2:




So, I thought I should share the scene and you may give it a try with any other engine you have access.
Of course, this is a quality/ability test rather than being a speed-challenge.

The scene has a blue studio ground, a dragon, a small emitter plane and a dim skydome as ambient to match the original reference.
But, you can use either of them or both or more when the features of the engine don't match (only emitter, only skydome or only IBL or all).

Here's the scene OBJ files (all pivots at zero, no further relocation needed):
http://www.fileden.com/files/2009/5/30/ ... ne_OBJ.rar

Resolution: 800 x 640
Lens: 85 mm

You may also try FBX file instead:
http://www.fileden.com/files/2009/5/30/ ... dragon.rar

...and Maxwell version is here:
http://www.fileden.com/files/2009/5/30/ ... dragon.rar

There are 3 goals in doing this:
1) Highly rough transmissive surface achieving blurry refractions.
2) Full caustics and TIR including the caustics on its own shadow.
3) Clear glass material core with no SSS/translucency or other effects is essential.

I want to leave this test open to any kind of render engine for comparing the quality of outcomes to Maxwell Render.
This is not a duel, so my respect goes to the ones which can at least succeed and demonstrate its quality in comparison.
And of course it's very sad for the ones which may fail awfully. Let's see... Awaiting for your renders...


COPYRIGHTS:
Dragon model by Stanford University Computer Graphics Laboratory.
Reference image rendering by Henrik Wann Jensen.


-Edit: Building the table of entries... Below is the current state:

[rusteberg]

does your dragon use standard frosted glass from wizard?
edit: i retract my question with the assumption that it does...

[tom]

Yes, additionally it has a duplicated BSDF at low rough 25 weighted at 30 for glossy speculars.

[rusteberg]

gotcha, thanks.

[rusteberg]

i really like the concept of this thread. i only hope that others with access to other engines (as well as those with the same as those who do in fact post here) will take some time and post examples of comparison. i think it would not only be interesting/helpfull to see comparisons of one scene/material in particular, but perhaps down the road multiple scenarios given various complexities within given context, as has been provided.... (anyways, that's my well formulated thought while trying to figure out whether or not to reply with any 'incredulous' substance)

[get aroused here...]

the most common argument i hear is that (generalized) "vray can render just as equally, or close to with cranked up settings" [get hot and furious here]
so that's where i decided to start testing... as i've only used vray a handful of times, i don't claim to be an expert. nor do i ever intend to be for in depth challenges such as this. that being said, if you do feel you are more experienced (with the know how of 'how' to get what you want using vray), and believe you can achieve a greater result than what i'm showing here, then please feel free to pm me (or email me tom|at|wanderplay.com) and i'll send you the max file i've used to create the example below..... i'm eager to see a better, more qualified example given my knowledge of the application...

anyways, here's an attempt at comparing one render with another. note there are two examples comparing the 'stray' with maxwell. the first one compares vray raw output with maxwell (both maxwell comparisons are raw output based on frosted glass wizard material with "duplicated BSDF at low rough 25 weighted at 30 for glossy speculars"). while the second compares a post pro attempt from vray to try and match maxwell using several elements including; raw refraction, raw reflection, and an inversed AO compiled in photoshop with color correction added....

roll over images to compare.... (used same scene/camera for both images for direct comparison. thought it would be helpful)





...... sorry, that's the best i could do. hope it's useful. would be eager to see a better example.

[tom]

Thanks for your contribution! It's respectable Vray can come closer. It's still miles away but at least it can render something like frosted. Now, I wonder which other unbiased engines will attempt to demonstrate their weakness here.

[Frances]

It would probably be better to base the challenge upon a photograph as the standard and not a render. Even rusteberg's (a gifted Maxwell user) Maxwell render doesn't look like yours.

[tom]

You're welcome, Frances. Of course, we can start it in another thread. This thread is only for the Jensen's Frosted Glass Dragon and it's a valid reference. If you could contribute with Fry Render, it would be a great help.

[Frances]

So Jensen's render is the benchmark. That's interesting. I would consider it inappropriate to contribute a fryrender or an Arion image considering my position at RandomControl. But thanks for the invitation.

[rusteberg]

It would probably be better to base the challenge upon a photograph as the standard and not a render. Even rusteberg's Maxwell render doesn't look like yours.

the balance of light shown in my example is off from tom's original... i had set it up that way to try and get the speculars close to each other...

rollover below. this is the same render used for comparison above... image lit with only skydome. the other only with staged emitter based on provided model. same rendering, different results.

thought it would be cool to see the difference within same render

[tom]

So Jensen's render is the benchmark. That's interesting.

It's one of a good example as a frosted glass figurine render, no doubt. That does not mean it's the ultimate benchmark but still a decent reference render. Also, I'm not avoding to compare against photography. It's just because this is very obvious and no complicated setup is needed.

I would consider it inappropriate to contribute a fryrender or an Arion image considering my position at RandomControl. But thanks for the invitation.

Why not? Personally, I could exhibit my Maxwell images anywhere and Next Limit management could only be proud of it.

[Fernando Tella]

May I ask what's your position at RandomControl, Frances? I have only a vague idea. Only beta-tester or something else?

[Frances]

It's one of a good example as a frosted glass figurine render, no doubt. That does not mean it's the ultimate benchmark but still a decent reference render. Also, I'm not avoding to compare against photography. It's just because this is very obvious and no complicated setup is needed.

Photography should be your benchmark.

I would consider it inappropriate to contribute a fryrender or an Arion image considering my position at RandomControl. But thanks for the invitation.

Why not? Personally, I could exhibit my Maxwell images anywhere and Next Limit management could only be proud of it.

Sometimes protocol must trump pride.

[tom]

OK, Frances. I think Maxwell community is smart enough to appreciate your excuse.

[Frances]

OK, Frances. I think Maxwell community is smart enough to appreciate your excuse.

And you should be smart enough to appreciate the difference between a reason and an excuse.