renders from saved solution taking ages

[tricky]

I am rendering an animation.
I have pre-calced the irmap solution - primary as IRmap (medium), secondary as QMC 10 bounces.
To speed things up, I sent three frames of the solution (which I am calculating every 25th frame) to a different machine, eight machines in total, and then merged them together using the Irradiance Map Viewer.I then set the renders going.

They seemed to start off pretty quickly at 10 minutes per frame, but the camera is now going around a small internal glazed atrium and the render times have shot up to 2 hours per frame. The strange thing is, when I render one of these frames locally it renders in 12 minutes, even with the calculation of the Irmap as well!

Could a merged solution be causing me problems? I am using 1.47.03

[jacksc02]

how big is your imap tricky?

[tricky]

about 40MB.

It was calculated every 25th frame: renderbox 1 did frame 1000, 1025, 1050. Renderbox 2 did frame 1075, 1100, 1125 etc etc. It was set to medium animation, but with GI blur set to 0. Secondary bounce was QMC with 10 bonces.

I then meged all these IRmaps together.

Where there isn't much glass, renders are around 10 mins per frame. Where glass is close to the camera, the frames are between 2 and 4 hours each!

When I render a frame locally, calculating a low quality Irmap at the same time, the render takes around 12-15 minutes.

Why is this? Any suggestions?

[jacksc02]

you would be better off rendering th IRmap using incremental add on 1 computer.
I think there might be a problem with the IRmap you have.