Please…
i have to do one pic with 2480 x 1744 but i dont know
wich settings put in min and max rate in irradiance map…
actualy i have testing with high (-3 and 0) but is very very slowly…
anybody can tell me what can i do??
thanx a lot
do you have materials with glossiness?
there is a rule of thumb .. but i just normaly render the image half the size, save the IRR map then render your image at the size you want from the saved map 
thanx… i will try… and will post result…
Hey that’s exactly what the min max settings do for you 
There’s lots of info on www.vray.info about these settings.
i actually find playing with the hsph subdivs and the interp amount can greatly reduce times allowing a higher resolution map to be created.
when doing previews i use -3-3 (Antialising off)on the map and 15,15 on the hsphr and interp…when going to high res (4000x3000) i use -2,-1 on the irmap, wind hsphere up to 30 or 40 and interp from 50-100…antialiaing is 2 & 4, i find 6 is nicer but it has a noticable effect on rendertimes.
I also force glossies to have one bounce.
I found rendering bucket ir map would shave perhaps 10-20% off render time, but i couldnt guarentee i wouldnt see artifacting on the GI on where the buckets met.