vrmap file??

[tri-xy68]

I am new to Vray and have been trying to get the rendertimes down. I found a tutorial or someone told me to render a very small size image with all the settings I want for my final image and to save the vrmap to a file to use later with a large size render. I have tried this and seems to work very well in theory as the very small rendered image takes a very short time. I now use that file and generate the larger image. So far so good. The large size image renders very fast, which is great, but it is extremely dark?? Am I doing something wrong? I am using single frame mode, which the person that suggested this to me said to use bucket mode but I don't think that would make that much difference?? Anyone have some advise. It would be great appreciated.
Thanks Peter.

[natty]

Hi

well what you should really do is render out an Irr map @ half the size of the fall size image that you want to render. When the Irr map has rendered you need to load that in ... so choose from file.. then render azt your production size and increase the AA a Little just to sharpen, because the Irr map will be slightly Blurred.

edit :: in the global settings it would be a good idea to turn off render final image

[tri-xy68]

Thanks for the response Natty. Here are my settings.

image sampler(Antialiasing) -

simple two-level - base 1, fine 4

GI - first bounce - 3.5, Irradiance map (high) (-3,0)

secondary 0.75 (NONE checked)

Irradiance map - Single Frame

Is it optimal to only generate and save the Irradiance map for half size of the final image? Are there any other settings I could lower for calculating the map and then punch up for the final image?

I thought on a different project I was using like 240X340 or something and then using that vrmap to calculate 2400x3400, I may be mistaken. I'm just trying to find the optimal because my model is getting quite large as I am using it for design testing of interior and exterior as well. Thanks again for any help.

Regards Peter.

[percydaman]

I wouldn't use a vrmap thats less then half the size of the final output. especially in the instance you provided. Also unless you have alot of glossy materials or DOF, Moblur, I would use the adaptive AA as opposed to the 2 level, itll be faster. Finally, I personally only use a max of 0 for the irradiance map when its really necessary. If you can get away with using -1 for the max, then Id go that route.