LC & IM settings vs render speeds

[bhchllc]

We have a simple speed related question I was curious about.
Does your IM and LC settings have an affect on how long the actual render takes after the IM and LC passes are processed or does it affect only the time required for those particular passes. You would tend to think they would only affect the associated passes but our test seem to indicate otherwise although they are not conclusive.

[bhchllc]

So I just ran a few tests trying to be as empirical as practical without taking too long.

Two LCs were run and saved - one at 100 and one at 500.
Same scene was rendered using each pre-rendered LC with a low IM generated at render time. Render times were roughly the same.
Conclusion = # of LC subdivisions don't affect actual render times after the LC is calculated. No idea about sample size or the various other settings.

One LC was loaded from memory and 2 IMs were run and saved, one Very Low and on High. Same scene was rendered using both IMs and the render times were 7:33 for Very Low and 7:36 for high - basically the same. Concluson = IM settings only affect time required to calculate IM but have little to no affect on the time to complete the actual rendering.

Clearly these are far from empirical and obviously don't apply settings like detail enhancement and "use LC for glossy rays".

Does this seem to gel with other's experiences, Vlado - sound right?

[deneb26]

hi
well not really. try to increase the intr. smpl. for the IrrMap and you'll see that rendering times also increase.
the same thing happens with the Filter-Size for LC. the higher the value the longer the rendering.

ale

[glyph]

somewhere else Vlado has said that render time tends to be roughly proportional to precalc time - but it will depend on your scene a lot if the higher settings are not in fact generating significantly more detailed maps