Newbie really Need Help: Speed up Rendering (Rhino & vray)

[legene8]

Hi all,

i repost my question here.. previous one was too vague i know.

My simple Night Render is unable to render within 7 hours in the settings i used. I using vray sun & some direct lights.

It is ok when i render my building alone. But when i put in my background buildings/ roads, it gets super slow that it is still 'building light cache' when i came to check on it. I have read read many threads on 'how to speed up rendering'. But i am too novice to detect the problem in my own settings. So i would really need some insights from professional... ;(

I have hid many background items, and exploded all of them. What could be the cause? Should i remove 'materials' on these background items?

Here is my current settings:

Image Sampler:

Adaptive DMC, min subdvs 1, max subdvs 6, noise threshold 0.005

Antialiasing Filter: On, Catmun rom.

DMC Sampler (default)

Adaptive amt 0.85, min samples 8, noise threshold 0.005, subdvs mul 2

Indirect illumination (GI)

Primary GI engine: Irradiance Map

Secondary GI engine: Light cache

IR Map

min -4, max 1, hsph 70, samples 50

Light Cache

subdvs 1000

sample size 0.02

number passes 4.

scale: screen.

I needed this on A2 size paper, so my output is 2048 x 1536.

Are my settings above ok to produce quality image also?

ahh sooo stressed out..

Please help... & thank youuuu lots!

Becca

[Bruce Hart]

Hello Legene,

I can empathise with your getting to grips with the numerous Vray settings, however a bit more reading and understanding about what these settings are doing will certainly help you in the future. These settings are very high for an exterior render.

 

For example - The IR. A Max rate of 0 means that that maximum precalc resolution Vray will use to analyse scene detail for IR samples will be the same as the render output resolution. A max rate value of -1 will be half the final output, and -2 half that again. Since you have a Max rate of +1, you will be getting a precalc of double your output resolution. In other words Vray will be rendering at 4000 pixels wide to determine IR detail, when it has probably seen enough at 1000 pixels wide (or even less). Just try the default low or medium IR presets for starters (Min Max -3,-1 HSph 50, Int 20) the default AA DMC of 1,4 and the global subdivs of 1. Maybe you saw these settings for some very detailed interior, but these are not applicable for a massing exterior. You could drop your LC to 500. When at full render res you could try IR of -5,-2.

 

You could probably render around 3000 - 3500 pixels wide for A2 if it's just a massing model. Once again you just need to read up a bit more on IR and how it relates to your render resolution.

 

Check out the "practical exterior lighting" on http://www.3dats.com/free/.

This is in MAX but should provide some guidelines.

 

Good luck

[Nic H]

do you ahve displacement on? sounds liek you have loads of geometry/displacement if your lightcache is struggling...

need more info - could be anything

 

your IRR map is overkill as well.

[legene8]

To Bruce & Nicnic, thanks for your kind reply!

 

@bruce: yes i have read up these settings for interior renders. I will try render with your suggestions! sigh... there is so much to learn... since i am vray self taught, i read only bits & pieces on the net.

 

@nicnic: it could be geometry problem, cause it is only the background buildings/ ground that are difficult to render. Rendering my building alone is fine. Do you mind to point out where i could turn off my 'displacement'?

 

thank youuu guyss... appreciate it!