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ingo
04-10-2004, 03:58 AM
...or so. I have a strange problem and i remember i heard about this before. I rendered a picture with enhanced medium aa, aka 9 rendering passes. Normally you can easily calculate the complete rendertime when you watch how long the first pass renders and multiplicate it with the number of aa passes you render. But in this case the first aa pass rendered 40 min and rendertimes are going up by every pass, so the last pass took 4 hours. How can this happen ?

The picture size is normal print resolution, 4480 x 2520 pixel, around 2.700.000 polys and i rendered in a single pass, so everything as usual here; and i used interpolated raydiosity fwiw. Overall rendertime was now 18 hours.

Aegis
04-10-2004, 05:49 AM
If I recall correctly this is a known bug with cached radiosity - turning off "Cache Radiosity" should fix it although then you could end up with "boiling" shadows as the interpolated radiosity is calculated on a per-frame basis (although this won't affect your print rendering) - I rarely (if ever) use interpolated radiosity 'cause it just doesn't work as well as it should - Monte Carlo or bust baby :D

ingo
04-10-2004, 08:39 AM
Hmm, cache raydiosity is off, so thats not the problem. Maybe because it needs a lot of memory, the same happens now with as second picture. Rendertime overall is 50 % higher than "normal". Overall interpolated raydiosity gives good results, its fast and with motion blur quality is good, no problems so far till yesterday.

Aegis
04-10-2004, 10:14 AM
Maybe it's just an interpolated radiosity bug period. If so, here's hoping it's fixed in 8... I always seem to get less than satisfactory results using interpolation - occaisonally I get something that I think looks good then I realise that the only reason it doesn't look "splotchy" is because the samples are too large which of course means the results are incorrect. If I use radiosity it's normally background or Monte Carlo and I try and bake it wherever possible (although I've got FPrime now so whole new vistas of possibility are open for animations ;)).

ingo
04-10-2004, 11:11 AM
Originally posted by Aegis
.. I always seem to get less than satisfactory results using interpolation - occaisonally I get something that I think looks good then I realise that the only reason it doesn't look "splotchy" is because the samples are too large which of course means the results are incorrect. ...

Well thats exactly how i use it, make it so that the splotches are big enough, and if i need special exact shadows i use ShadowDesigner, works quite well. Lightwave 8 its still very late... ;)

Gordonpee
04-10-2004, 01:12 PM
I had the same problem using Hypervoxels on my Dual G4. Someone had suggested using only 1 thread and that cleared up the problem.
Now whenever I need to render Hypervoxels, I just have to remember to turn off multi-threading.

Gordon