Slow to start rendering with HDR lighting

[tricky]

I'm not sure if this is really a problem or just to be expected when using HDRs as the dominant light in a scene. I have recently acquired a few of Peter Guthrie's HDRs and am enjoying using them. I am following his guidance on loading them into a vrayHDR map and dragging an instance of that into the texture slot of a vray domelight.

To get renders done, we use DR almost exclusively. Our network is gigabit, and in general, the speeds are pretty good. However, scenes just seem to take a good deal longer to start rendering on the render nodes - on small renders, most of the GI is done on the local machine (LC/IRmap) before the nodes kick in to help out. I am pretty sure this wasn't the case when using a simple vraysun/vraysky setup.

Of course, I expect some slowdown, but I am surprised by just how much, especially as the Peter Guthrie HDRs are only around 30MB in size.

I wonder if it would make a difference using the EXR versus the HDR?

[vlado]

What resolution are the HDRs?

Best regards,
Vlado

[tricky]

resolution is 7144x3572

[peterguthrie]

hi tricky, I had a very weird issue ages ago, and i'm afraid I'm struggling to remember what solved it.

http://forums.chaosgroup.com/showthr...ayHDRi-problem

[tricky]

Interesting. Maybe I'll try putting your HDRs in a max bitmap loader instead. Presumably I would just set the mapping to Environ/Spherical environment? How about horizontal rotation?

[peterguthrie]

then the horizontal rotation is controlled by the u offset, and is on a scale of 0-1 (and rotates the opposite direction to the vrayhdri and even starts at a different point just to keep you on your toes).

[tricky]

then the horizontal rotation is controlled by the u offset, and is on a scale of 0-1 (and rotates the opposite direction to the vrayhdri and even starts at a different point just to keep you on your toes).

Bloody hell. I've got a little post-it sticky on my monitor with the rotations for your HDRs too! Now I'll have to make another one! lol.

[peterguthrie]

annoying huh? out of interest, what OS are your slaves running? I think my problem was solved by installing win7 on the problem one.

[tricky]

XP (3 nodes) and W7 (6 nodes)

[dlparisi]

Sorry to revive the old thread...

Did either of you confirm what was causing the slowdown? I've been having problems with several dr nodes being slow to start except I'm not using any HDR maps. What appears to be the case is that any of the DR nodes that are XP take significantly longer to load the bitmaps than an identical machine (other than the OS) running windows 7. I don't believe it's a network congestion issue as it persists even if I use only one of the nodes at time. If I switch off "Maps" in the Gloabl options rollout then everything is nice and speedy on all machines. Just trying to figure out is a OS upgrade is necessary for the offending nodes.

Thanks.

[peterguthrie]

Installing win7 solved my issue (was vista previously)

[dlparisi]

Thanks Peter. I've got three nodes that would need the upgrade so I think I'll just bite the bullet on one and see how our goes.