Photon Mapping problem...

[larco]

Hi!

First: thank you, GoncaloP, for 'tutorial'

Second: the image

problem: that spots on the corners (on ceiling, near the beam)....

anyone knows, whats wrong?





Thanx & greetings!

[GoncaloP]

The problem use to be related with a lack of photons (subdivisions)

Gonçalo

[ventil185]

I had the same problem, just try with Retrace threshold 2,0 insted of 0,0

that worked for me.

Guilherme

[larco]

Thank you for FAST replies!

GoncaloP, my Master Of Photons! )
Do you mean subdivs in light properties (under Vray > system)?

ventil185:
OK, i'll try that, but... what is Retrace threshold? it isn't described in vray help... How do it works?

Larco

[ventil185]

ventil185:
OK, i'll try that, but... what is Retrace threshold? it isn't described in vray help... How do it works?

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

Just go to this page and look at the end of the page, last set of text, it gives you and idea of what retrace threshold is.

Guilherme

[larco]

Thanx guys! It works!

retrace: 5

Guilherme: I'll look at that



Larco

[ventil185]

It´s very nice!

Guilherme

[larco]

Thanx for help, guys!

Larco.

[Biostat]

Wow that's beautiful, superb work!

[larco]

He he, thank you, Biostat, but wait for final image! That is only empty interior! ;D

But for all what i've done, I must say: Thank you, Goncalo, for your great 'totorial' about photon mapping! Thank you, Guilherme for your tips!

Larco.

[larco]

OK, i have rendered it with more details and colors, but...
why those two lights in the bar looks so strange?
uh, and rendertime... i know there are a lot of glossy reflections, but...
(Athlon XP 2000+, glossy on wood and tiles - i've looked at real samples for few hours)

[dusan]

Whoa! I think You didn't have to increase the lights subdivision that much! Try it with 400 up to like 600 maybe, see how it looks like, 5 hours for that image is too long.
Put a white or light bluish color as background, first it will look much better since the directly lit parts are real bright and second you will get much better glossy reflections!

Those light look really weird, as does the reflection under the nearest fence pillar, not sure what this is, might have something to do with the photon setting, you have those splotches all over the image, like under the window on those shelves...

[larco]

more reasonable time
oh! add to it about 1,5 mins for calculating photons.

it requres one more pass (for now it's -3/-1), and some other tweaking
if you have any ideas - write!

again, thanx for all tips!

PS: with that bar lamps - nothing help...

[dusan]

Why don't you try with retrace treshold increased?

[larco]

I know, I know...
I have tried, but now (with glossy refl. only on floor and steel) 560x320 takes sth. about 40 minutes! (athl. xp 2000+)

any tips to make glossy mats. render faster?

my material settings:
reflect: white (max)
gloss.: 0,7
subdivs: 8
fresnel: on
max depth: 1

checked under 'Options':
trace relf.
trace refract.
trace diff & gloss together
double sided
use irrad. map