just to be of some help, let me do the math in reversed way: how much texture does one need? Just to give you some clues in advance.

a) texture maps need to be at least twice the resolution of your render, so 1MP (megapixel 1000x1000) render requires 4MP texture visible.

b) Each object on the avarage is at least 25% visible (50% when full in camera, 75% with mirrors in the back etc), so 1MP render result requires 4MP /25% = 16MP full texturing.

c) using texture on texture, like decals, diffuse + specular + bump but also dress over figure etc, makes another factor 2 to 6, so let's say each 1MP render takes 16x2 to 16x6 or 30 - 100MP texturing.

d) in my first post, I mentioned 1500x1500 EXR requiring over 10MByte, so say 1MP texturing takes 5MB storage, and as a result 1MPixel render takes 30x5=150 to 500MB Texture Cache.

So when facing < 100MB per MP, one has to rethink his texturing for quality reasons. When facing > 500MB per MP, one has to rethink his texturing for performance reasons. Especially when doing fine print (5000x7000=>35MP/image) or real large screen cinema, texture management means something (for instance, the Jurassic Park T-Rex took 4GB on textues alone).

BTW: I dedicated a (4GB flexible) portion of my (24GB) physical RAM to a RAM-Disk which holds my texture cache. You can't get it faster. Sometimes, a new massive background set does not fit. Then I copy/save its texture folder and run Photoshop on the original folder, halving all texture resolutions. and again, if required. Only when I need the hires ones for the grand final poster size result, I a) swap texture folders and b) point the TextureCache folder to somewhere on HD. Will take forever, but so will the render (overnight job) so who cares.

just thinking with you, take your pick to suit your needs.

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Usually I'm wrong. But to be effective and efficient, I don't need to be correct or accurate.

visit www.aRtBeeWeb.nl (works) or Missing Manuals (tutorials & reviews) - both need an update though