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Glyptic
02-09-2006, 11:10 AM
Hi,
I'm running a render (its at 9 1/2 hours now) that is running extraordinarily slow.
I've run renders of the same scene in 1-6 hours depending on settings. See my recent earring post, thats the scene.
I've added 80% dispersion to one gold material in the scene.
Does that increase render time by about 300-600%?
I've got HDRI/Gi lighting, AO on two materials, Best AA. And 1.5 million polys which is because of a texture (high poly for STL output).
GI Normal setting are kinda high, like 300 Stoch samples, Min. res 75 and Max res 250. 50% accuracy and only 1 Difuse Depth.
At the current rate this render is going to take 24-40 hours. OUCH!
What's going on?
Thanks in advance for the insights.
glyptic

AdamT
02-09-2006, 02:47 PM
Are you using 9.5? Blurry effects do increase render times, but the hit was reduced substantially (by a factor of 2-5) with 9.5.

Glyptic
02-09-2006, 03:07 PM
Hi, Adam,
Yep, I'm using R9.52 with AR 2.5.
The first part of the render went fine. Then it hit a brick wall when it came to the gold "ball" motif with the texture, dispersion and zillion polys.
Would there be much of a differrence between say 20%, 50% and 80% dispersion?
I just chose 80% for yucks. And to make sure it was pretty matte.
I *really* like the effect. It's a lot like a glass bead blasted finish.
cheers,
glyptic

AdamT
02-09-2006, 04:39 PM
Yes, I the render time goes up as you increase the dispersion %, but it probably won't make a huge difference.

Something else you might try is rendering a separate reflection pass and blurring it in post.

Glyptic
02-09-2006, 05:05 PM
Thanks for the suggestion, Adam.

Well, looks like another reason to suffer through those PhotoShop training DVD's my brother gave me. The presenter is insufferable. They really help me appreciate how good the 3D Fluff DVD's are. Hey, maybe Janine could do some PhotoShop DVD's for Cinema users?
I know I'd buy them.

Actually, render times that correspond to my sleep cycle are just fine. Its when the extend over calendar days that I get impatient.
I'm looking forward to seeing the render when I get home from school.
glyptic.

Simon Wicker
02-09-2006, 05:11 PM
hi glyptic,

render times increase vastly whenever you use reflection/transparency in a material that is rendered using GI. one trick you can use if you have very reflective/transparent objects is to go into their materials and under the illumination tab set generate and receive GI off (so these items will no longer receive or generate indirect illumination).

the finished result should be almost identical to the GI illuminated version but should render much faster.

alternatively i wouldn't bother using GI at all, just use area lights to light the jewellery and then use a HDRI for reflections only.

cheers, simon w.

Glyptic
02-09-2006, 06:18 PM
Hi,, Simon,
Great tips, thank you.
Printed and put in my C4D Folder.
I'll play with those ideas when I get home.
cheers,
L

Glyptic
02-09-2006, 10:21 PM
Well, I got home to find my render is now up to 20 1/2 hours. And looks to be about half done. Which is a bit artificial, as the matte gold is almost all done, and now it will move to materials without any dispersion. So maybe I'll be done with it in the next 10 hours or so.
This is humorous actually.
I look forward to some work arounds that cut the time down to my wakeless hours.
And thanks to the info you guys have been so generous to share, I'm on the trail of a solution.
cheers,
glyptic.

Glyptic
02-10-2006, 12:05 AM
Ok, here is my 21 hour render.
I'm happy with what I've learned and look forward to cutting the time down a bit.
Getting a decent matte on the gold, and combining it with some high polish is a wonderful discovery.
Thanks to Simon and Adam for all the help.
Maybe I can post something with similar qualities and a 10 min. render time.
Ha, ha.
cheers,
larry

hightillidie
02-10-2006, 12:45 AM
Thats waaay too much time for a simple render like that. Stochastic renderosity really fcuks you up. Better use Standart.

Glyptic
02-10-2006, 01:00 AM
I did use Standard GI. I think my 1.5 million polys in the matte gold panels (which are necessary for the STL output) and the 80% setting for Dispersion in the Reflection channel of my gold material contributed to the excessive time.
Oh, and the Best AA setting.
Other than that, there was nothing out of the ordinary in my settings.
Of the 21 hours, about 19+ of that was those textured gold "balls". Everything else was bim, bam, boom.
As long as its fun and I learn ways to get better (faster), I'm cool with it.
cheers,
glyptic

dAfTiE
02-10-2006, 08:54 AM
I did use Standard GI. I think my 1.5 million polys in the matte gold panels (which are necessary for the STL output) and the 80% setting for Dispersion in the Reflection channel of my gold material contributed to the excessive time.
Oh, and the Best AA setting.
Other than that, there was nothing out of the ordinary in my settings.
Of the 21 hours, about 19+ of that was those textured gold "balls". Everything else was bim, bam, boom.
As long as its fun and I learn ways to get better (faster), I'm cool with it.
cheers,
glyptic

couldn't you do a lighter poly count for rendering purposes?
It's all about cheating,after all.

Glyptic
02-10-2006, 11:34 AM
That is an alternative I'm looking at. The problem is that these models are designed to be prototyped and manufactured, so I would then have to copy the texture *for real*. Which could, or could not be much fun.

It would be relatively easy to make up some models to experiment with. If matching the textures were easy, then it becomes a real alternative.

Good idea, thanks.
glyptic

AdamT
02-10-2006, 04:07 PM
Looks great, but those render times are a bit crazy. I'd go with Simon's suggestion re: no GI. Then you might want to use a little ambient occlusion on the floor material (AO shader in the Diffusion channel) to get that GI-type shadow on the floor.

Glyptic
02-10-2006, 04:24 PM
Hi, Adam,
I used the HDRI domes only on the gold, but did click GI globally. The HDRI really helps me get the gold to look like *something*, otherwise, its pretty lame. Which is because I do not really have an "environment" to create reflections to help define the gold as such. The HDRi solves that very conveniently.
The floor does have AO applied (as does the textured gold) , as it really knocked up the "dirt" around the bottom of the stones and helps with shadows in the texture of the gold.
I'm going to have to try the HDRI for reflection only, and use Area lights for illumination.
That sounds like a good trick.
One disappointing aspect is how the jpg I save just doesn't look as good on my household computer as it does within Cinema. But, that's life.
Thanks again for all the help.
Slowly but surely, I'm feeling like progress is being made.
cheers,
larry

Glyptic
02-11-2006, 07:54 PM
Hi, Simon,
Attached is a render using some of your suggestions.
No GI, HDRI reflection dome only, and GI switched off on the gold material with the zillion polys. Illumination is with Area lights.
Render time: 62 min. with Best AA and some AO here and there.
I did another with GI on, but Illumination Dome turned to 0%. Render time: 13.5 hours.
And looks almost indentical to the 62 min render.
Thanks a million.
This is very cool.
cheers,
glyptic
ps The black might be a bit strong. But that's easy to change.

Glyptic
02-12-2006, 06:55 PM
OK, last WIP. I'm finished with this sucker.
Time to move on.
Thanks again Simon and Adam. Your insights *really* moved me forward on the jewelry render track.
Next WIP will commence soon.
cheers,
glyptic.

AdamT
02-12-2006, 07:57 PM
Looks excellent, man! Glad Simon's tips could be of use. :)

Glyptic
02-12-2006, 10:48 PM
Hi, Adam,

Thanks for the comment and encouragement.
I'm very happy with what AR 2.5 and the Cinema community has done for me.
Seemingly simple tips can make all the difference.
And thanks again to Simon.
cheers,
larry

mindful108
02-13-2006, 02:16 AM
Really nice looking render Glyptic.

Great tips Adam and Simon! :buttrock:



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