reflected light questions

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fulvio
Posts: 28
Joined: Fri Jan 12, 2007 7:04 pm
Location: Italy

reflected light questions

Post by fulvio »

My question is about noise of reflected light and how can I reduce, if is possible, the time render.

The first image "test.jpg" is render with some material problem, than I've used to see the global light result and correct the error.
The main problem was the noise of reflected light near JDC logo that is visible in "test-part.jpg"

This is my kray settings
Photons preset - medium (photonmap, emitted, multipler 4.0)
FG preset -low
Sampling - medium grid 3
Quality preset - medium but with luminosity threshold 0,01 - min100, max1500 (reflec/refract min100, max1000)

Image resolution 2048x1536
Time render about 13h

In the scene there are 50 poly light (part with autopart plugin) and 7 lw light.

I've tried to activate the "trace direct lights reflections" (to try to resolve the noise of reflected light) and the result is the image "def.jpg" .... but about 28h at 2048x1536 resolution.

In the image lw_ligt and poly_light there are my light setup.
Can You help me with some advise for kray settings ??

Thanks
Attachments
lw_light.jpg
lw_light.jpg (197.55 KiB) Viewed 3102 times
poly_light.jpg
poly_light.jpg (87.25 KiB) Viewed 3106 times
def.jpg
def.jpg (151.64 KiB) Viewed 3122 times
test-part.jpg
test-part.jpg (89.17 KiB) Viewed 3117 times
test.jpg
test.jpg (122.34 KiB) Viewed 3142 times
jure
Posts: 2142
Joined: Thu Jun 02, 2005 6:53 pm

Post by jure »

I'd use less reflection on the wall and turn down max rays for refl/refr blurring accuracy limit (100-200). There also might be issue with bump causing those specks.

I also wouldn't use lumi polys to light this scene. Spot lights should work just fine. Try to simplify your lighting.

Also.. what are those linear lights?
- Jure
fulvio
Posts: 28
Joined: Fri Jan 12, 2007 7:04 pm
Location: Italy

Post by fulvio »

jure wrote:I'd use less reflection on the wall and turn down max rays for refl/refr blurring accuracy limit (100-200). There also might be issue with bump causing those specks.

I also wouldn't use lumi polys to light this scene. Spot lights should work just fine. Try to simplify your lighting.

Also.. what are those linear lights?
Thanks for Your reply.

I'd not much time for this work and I've used poly light for fast (light) setup.
For the best render speed, when it's possible it's better to use spot light instead of poly ??

Linear light is for simulate neon above tube of air-conditioner.

Now I try to setup the scene with spot light and to change the brick bump map and to lower the refl/refr settings but, when it's right to use "trace direct lights reflections" ??

Thanks
jure
Posts: 2142
Joined: Thu Jun 02, 2005 6:53 pm

Post by jure »

pixeldust wrote: I'd not much time for this work and I've used poly light for fast (light) setup.
For the best render speed, when it's possible it's better to use spot light instead of poly ??

Linear light is for simulate neon above tube of air-conditioner.

Now I try to setup the scene with spot light and to change the brick bump map and to lower the refl/refr settings but, when it's right to use "trace direct lights reflections" ??
Use spotlights when your lightsource is small. This way you can stay in indirect render mode. Once you add luminous polygons you must switch to direct mode.

Trace direct lights reflections allows point and linear lights to be visible in blurred reflections (similar to specularity), also area and lumi lights are sampled like direct lights with the same pros/cons.
- Jure
fulvio
Posts: 28
Joined: Fri Jan 12, 2007 7:04 pm
Location: Italy

Post by fulvio »

Thanks Jure, Your advice are very useful.
I've used lw spot light and this render is better of my previous ...

I do some other test .... thanks.
Attachments
cam02-SPOT-0200000.jpg
cam02-SPOT-0200000.jpg (118.38 KiB) Viewed 3110 times
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