awful problem

[arqestevez1]

ok, why do those light spotts appear?
that always happens to me.
i'm posting the parameters that i used.
please, help

[fpedrogo]

Re: awful problem

Hi Arqestevez
Can you send me the file with the textures. I will look at it.

fpedrogo@asgvis.com


Best

[arqestevez1]

Re: awful problem

hi fernando.
i'm sending it

[fpedrogo]

Re: awful problem

Hi Arqestevez1
I already reply your by email, but for some one that are fallow this post the main issue is the Adaptive amount under QMC Sampler in the old version. This option make V-Ray more or less adaptive. The default value on our old version is 1 (100% adaptive) and produce splotchiness, in our new Build that value is .85. We found that this value is optimal for all of the render.

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[arqestevez1]

Re: awful problem

yeah, thank you very much fernando.
i also rendered with quasi montecarlo and reduced hdri's multiplier for the gi. both things by separate also correct the problem.
i have to finish this for tomorrow in the morning, so i guess i will be posting the final image in the vray for sketchup gallery, and will post the link here.
good night. and thank you again

[arqestevez1]

Re: awful problem

here's the final result (as far as i could get)
rendered with irradiance map and light cache, but reduced hdri's intensity and instead used some rectangular lights.
plus changing the adaptive amount to .85.
i still have some little spots in the ceiling at the left part of the render, but it is okay for now.
http://forum.asgvis.com/index.php?topic=7175.0

[Jackson_cg]

Re: awful problem

I'm curious why you're using a high IM HSph. Subdiv setting of 120, but extremely low Min and Max rates of -5 and -2?

I never go below Min and Max rates of -3 and 0 for final renders.

[fpedrogo]

Re: awful problem

Hi
Depending of the image si9ze Irr Map -5, -2 could be not so bad, but if you have to increase the quality of the rays that high 120, maybe will be good idea throw more samples instead of increase the quality. In the scene that you sent me I use -4, -1 and Hsp sub 80 -90. Also your light cache sample are too low comparing with the subdivision. Maybe you have to increase the light cache subd. to 1600 or even 1800 for the final render.

I'm wondering if you are using a blurry HDRI for the GI(Skylight), this can help to reduce splotchiness and render time.

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[arqestevez1]

Re: awful problem

hi.
yes, in the final render i used a light cache subd with 1500, but actually, i was using those max and min rates because i understand that renders are faster... i always set them to -3 and 0 for the final... like in the tutorial... but to be honest, i still do not understand the concepts at all, so i'm really sorry if i confuse you guys.

[fpedrogo]

Re: awful problem

Use -3 and 0 for the final production render in a very high resolution is not right at all. The irradiance map has a direct relation with the image size. When we talk about rate we are talking in divide the image resolution by the rate value. For example 0 = final resolution, -1 = 1/2 resolution, -2 = 1/4 of the resolution -3 = 1/8 of the resolution. If you get a decent render with IM -3 and -1 at 800 x 600 resolution, if you increase the render size to 1600x800 with the same IM (-3,-1) , basically you are throwing the double of sampler unnecessarily. If you increase the resolution, you have to reduce the Irr Map solution.
I hope you can understand, This option seem to be very difficult to understand. In my first render some year ago, I increase my resolution and the Irr Map solution as well and my render seem to not have end, but I learned the lesson.


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[mjm223]

Re: awful problem

... If you get a decent render with IM -3 and -1 at 800 x 600 resolution, if you increase the render size to 1600x800 with the same IM (-3,-1) , basically you are throwing the double of sampler unnecessarily. If you increase the resolution, you have to reduce the Irr Map solution...

So, just to be clear on this:

Let's say I made a final render at 800x600 resolution with an IM of -3/-1.

Now, if I wanted to double my image size to a 1600x1200 resolution, what should I change my IM values to?

[fpedrogo]

Re: awful problem

So, just to be clear on this:

Let's say I made a final render at 800x600 resolution with an IM of -3/-1.

Now, if I wanted to double my image size to a 1600x1200 resolution, what should I change my IM values to?

-4, -2

[mjm223]

Re: awful problem

Sweet! So basically, whenever you increase the image size, you want to decrease the IM's min/max values.

Thanks, I'll definitely keep that in mind.