First project, help needed

[moshenko]

Hey there -

Well, this is project#1 with V-Ray advanced (1.09.03r). I bought the program specifically for this project, as it is a rather complex day-lit interior with an animated component. I'm looking for some tips on a few problems I'm having with this still image, plus any other feedback others might have. I've got a pretty tight deadline, so I'm not looking for total perfection! Here goes:



- Would it be better in this case to handle skylight via Vray lights with skylight portals, or just through normal Vray skylight (my current method)?
- I've had problems with VRay refraction in the glass: seems to go black unless I hide the glass while calculating irradiance map and unhide it for the render;
- Looking for speed increases. This image was done with Medium preset, 6 secondary bounces (direct computation), and adaptive aa at -1,2, and rendered (both irradiance map and image) at 1000x533. Total time was ~6 hours on a dual Xeon 2.4. I imagine that there are many ways to get time savings - where should I start?

I wish I had more time for this project, as I would probably experiment a lot more instead of rely on the goodwill of others Having said that, any help thrown my way would be greatly appreciated!

Thanks -

[tom schuelke]

hi moshenko

don´t know how difficult your deadline is.

but if you´ve got the vray liscenes, you now can get the new internal,

and with that internal you could increase your rendertimes more then three times.

I would use lightmap for secoundary bounces, and i-map for first bounce. only this would increase your rendring more than 2 times. also with this method, the question how to bring in skylight would get unnesscessary, because lightmap understands environementlight perfect, and no more need to use skylightportals und sophisticated fake methods.

it is as fast (or faster as photonmapping), but much much easier to setup.

so maybe just copy your whole max folder to another place and instal the new internal (this way you are able to switch easily between versions if needed).

Tom

[moshenko]

Thanks for the suggestion, Tom. I almost grabbed the internal version (I just got up and running yesterday), but decided against it at this time. My deadline is Thursday, and I felt that I was taking enough of a risk by implementing new software 4 days before the project is due! I've also got another license server running on our network (and a bunch of other jobs), and didn't want to run into any problems.

[dejaVu]

Welcome to the dark side moshenko.
A few suggestions:
1. Overall it's looking good. However, the lighting is a little flat and too uniform. Perhaps you should define areas of interest and plan your lights to focus on these instead of having everything well lit. Determine what your main light source will be, natural skyight/sunlight or the artificial hanging lights. This will determine the mood and overall look of the shot and help you to make subsequent decisions.

2. If you want to retain fine details in your area shadows and control how much light coming from your VRaylights, then don't use the Skylight Portal option. VRaylights give you more control generally but are obviously a little slower.

3. If you are doing a lot of test renders, try saving your IRMap and reusing it. Calculate the IRMap without Reflections and with glass windows hdden. This will make it faster and allow more light in.

4. Glossy Reflections combined with GI is probably the killer. You could try rendering the reflection out as a separate pass, and continue to reuse this in the final.

I did a tutorial a while ago with a space that posed a similar challenge. It may be useful to have a look.
http://www.osmosis.com.au/info/tutorials.htm

Hope you make your deadline.

[moshenko]

Thanks for having a look, Vu.

You are quite right about the overall lighting. At this point, I'm concentrating on getting a handle on settings and such. Plus, it's retail (grocery, no less), where everyone wants uniform lighting I believe it will eventually lean towards a natural light solution, though.

Thanks for the rest of the tips - I'm quickly gathering a checklist in my head for testing vs. production, speed vs. quality. The names of things change from software to software, but luckily the principles are pretty transferrable (I'm a regular Brazil user). Your tutorial was great, btw.

[nlo]

@tom:

only this would increase your rendring more than 2 times.

not much experience with that but i hope you mean "decrease"

[moshenko]

One additional question: I'm struggling with irradiance map calculations, namely that they are taking the bulk of the render time. This means that I am reliant on a single machine for 80% of the render job - not very efficient use of our render farm. What are others' strategies for high-resolution still images? I know that the irradiance map is not networkable, but can I get away with a lower quality map and adjust, say, QMC settings to utilize the power of many machines?

Thanks -