Another Render Test

[Jordan]

Hi guys,

I just wonder how far full irradiance in mantra can go.........

I am pretty depressed when look at those nice images from the maxwell gallery, brazil, vray... u named it....

I decided to give myself a try today.

Here is the reference photograph.

Here is the rendered image.

Here is the wireframe.

gotta apply some displacement map to make those surfaces imperfect.

Your critism is welcome. It will be great if u guys can share some insights

on how to make your mantra render as great as those renderer like brazil, maxwell... vray...etc...

Possible????

j.

[symek]

just on a side of your interesting tests

vray and brazil are nice/modern raytracers. Maxwell is unbiased/phisical based render system. One shouldn't mix these two worlds... Maxwell is invincible in photoreal as it treats rendering in different way... Way, way less usable then mantra - not only in rendertime sense.

I think that Vray and brazil are more like a set of nice shaders in general. The quality you see in their galleries comes mostly from bundled shaders. Those which Houdini doesn't serve. It serves the way to prepere then instead.

and at the end this are general purpose renderes (arch. visualisation mostly). Try them is serious FILM task...

Of cource I would love to see nice photoreal renders from mantra without any work: wash&go. Now I have to work on it!

cheers.,

sy.

[Jordan]

just on a side of your interesting tests

vray and brazil are nice/modern raytracers. Maxwell is unbiased/phisical based render system. One shouldn't mix these two worlds... Maxwell is invincible in photoreal as it treats rendering in different way... Way, way less usable then mantra - not only in rendertime sense.

I think that Vray and brazil are more like a set of nice shaders in general. The quality you see in their galleries comes mostly from bundled shaders. Those which Houdini doesn't serve. It serves the way to prepere then instead.

and at the end this are general purpose renderes (arch. visualisation mostly). Try them is serious FILM task...

Of cource I would love to see nice photoreal renders from mantra without any work: wash&go. Now I have to work on it!

cheers.,

sy.

hi, symek.

I agree with what u said.

In fact, i m quite impress with the major speed up of mantra in H8.

But when come to full irradiance, it's still the pain... long render time with unsatisfying result.

I wish mantra in H9 will be improved in terms of full global illumination and some kick-ass pre-build shader. i wish....

Here is the small little update. Irradiance sampling increased. it toke 45 mins to render on my small little laptop. No complain about the speed, just want to bitch about the gi quality........

Post processing in photoshop.

Next weekend, i still work on this same scene without full irradiance.

Gonna do some fake bounce light to see which way is more efficient...........

have a good one guys..

j.

[lisux]

Nice render Jordan.

Like seemek have said, is almost impossible to achieve the accuracy of maxwell like renderers due to the math behing them.

All of these have pros and cons, there are many threads about this discussio.

Anyway, apart from the displacements for your syrfaces I think you need a little of glosiness in the ground.

[Jason]

Nice going Jordan! I'd love to see more of this scene.

[Jordan]

Anyway, apart from the displacements for your syrfaces I think you need a little of glosiness in the ground.

your are right, lisux. need more glosiness on the ground.

infact, working on displacement with micropolygon smoothing while full irradiance turn on is a pain.

so i switched off gi_light, and worked on the glosiness and displacement on the ground.

Here is a small little update. U will wonder that the render image looks so much different without g.i

[lisux]

Now the ground is much better.

You haver disabled irradiance but nit ambient occlision not?

Yes irtradiance in mantra for the moment is a great speed problem

But the image is looking better.

[Jordan]

You haver disabled irradiance but nit ambient occlision not?

Yeah, now ambient occlusion is added.

Render time has been cut down from 45 mins to 23 mins.

But the non_full_irradiance render doesn't look as good as the full_irradiance one because of the color bleed.

You may want to share some insight on how to make your fake_gi render looks as good as the gi_render.

here is the latest update.

[lisux]

You may want to share some insight on how to make your fake_gi render looks as good as the gi_render.

Using bouncing lights and spending a lot of time

Anyway the image is very good. I like the glosssiness of the ground.

[pbowmar]

Don't forget to tune Mantra's settings as well. For example, set the grid and raytrace caches high, and also set the raytrace level of detail low:

mantra -L .01 -G 65536 -M 65536

if that looks crappy, turn up the -L value maybe to .1 or so, likely never have to go higher than .1 unless you have mirror-like reflections.

You might be able to go higher with the -M flag too, however there used to be a bug where too high a value would "wrap" and become something meaningless, so try 65536 first and see if that makes things faster. It will use more memory but not enough to worry about unless you have an insane amount of geometry which it looks like you don't.

Another thing to try is Raytrace only mode (mantra -r) combined with the above, that might be faster, or it might be slower, you'll have to give it a try.

Cheers,

Peter B

[lisux]

mantra -L .01 -G 65536 -M 65536

if that looks crappy, turn up the -L value maybe to .1 or so, likely never have to go higher than .1 unless you have mirror-like reflections.

I have made some tests with thiese setting peter and I think that it is great unless you have a surface with displacement. To get a decent result with this kind of surfaces, unfortunately almost all the surfaces I am rendering have displacement, I need to set the level of detail to 1, otherwise I get artifacts in me renders.

[pbowmar]

Hey Pablo,

Yeah, fair enough, I hadn't really taken that into account. Though, I recall reducing -L even to .8 or so on displaced surfaces gave a speed increase without artifacts. It's been a couple of years though

Cheers,

Peter B

I have made some tests with thiese setting peter and I think that it is great unless you have a surface with displacement. To get a decent result with this kind of surfaces, unfortunately almost all the surfaces I am rendering have displacement, I need to set the level of detail to 1, otherwise I get artifacts in me renders.

[Jordan]

Hey Pablo,

Yeah, fair enough, I hadn't really taken that into account. Though, I recall reducing -L even to .8 or so on displaced surfaces gave a speed increase without artifacts. It's been a couple of years though

Cheers,

Peter B

thanks guys(peter n pablo), for all the hidden gems.

next i going to replicate a render in mantra which a friend of mine did in max and rendered with vray.

It is a interior gi scene. I would love to see the different in terms of the gi rendering time and color bleed quality.

thanks.

j.