IES Lights - How many is TOO many?

[Blitterswitch]

I am currently working on my first real Vray powered project and I have setup the lighting to fit exactly with the RCP. I have also used the specific IES files from the light manufacturer on each light.

I am using an Irr/LC setup and my render times are about 10-15 mins for a preview at 320x480 or 1hr - 1hr30mins for an 720p HD res image.

This is more than acceptable to me - however I am experiencing some issues in generating a cache file for a fly through light cache in a decent amount of time, which I put down to the 300+ IES lights in the scene.

Am I completely mad to have 300+ IES lights in ANY scene or is it just a case of "Do whatever works?"

I am currently the sole visualiser within the company who uses Vray and have have no formal training or anyone to bounce concepts off which has made my life for the past month or so highly exhausting. I have been used to using Viz 3i and a dual processor Pentium 3 at the last company so this is all very exciting for me. I welcome any thoughts and ideas.

Thanks!

[Sawyer]

There is a comfort level that you have using IES lights that you can pass on the an architect and say this lighting is as accurate as you can expect. Yes they take a long time and there are times when you will remove them or modify a lighting scheme to match a time deadline. 300 is a lot but if it works... At this point the archi can come to you and say "I don't like the lights" and you can say that the lights are based on a file callibrated for this type of light that you got at this website. Even if they are not 100% real world values they are something concrete that you can view measure and adjust accordingly.

[vlado]

You can also switch the photometric lights to Spot distribution just for the irradiance map/light cache phase, and revert to web distribution for the final rendering. Newer V-Ray builds are somewhat faster for large numbers of 3dsmax lights, but still, the standard photometric ones were not designed with speed in mind.

Best regards,
Vlado

[Clifton Santiago]

I suppose if you want to try and say with certainty that the space will have a certain brightness, then you can use that many IES lights, but how often is that necessary? I usually avoid IES lights because of the time, and I often end up adjusting their brightness to look "correct", which defeats the whole purpose.

Instead I use max spots with inverse square falloff and just adjust them till they look right. I also may only use one spotlight for every two can lights. If they want the IES light patterning, I just fake it by putting a radial gradient ramp to simulate the desired effect, and put it in the projector slot.

Who do you work for in Manchester btw?