Post Tue Sep 06, 2016 1:25 pm

How many light source polygons are "many"?

Hey, i am new to all this rendering stuff and it feels a little bit overwhelming, but trial and error should help me fix this.

What I can't seem to overcome are the slow (?) renderings - so I don't even get to trial and error.

So basically I read abouth the mesh LS warnings, etc, but now the question occurs - how many light sources are "many"?
Just to grasp it, i went with a simple scene (4500 faces in Sketchup) of a simple object (hi-fi amplifier). So, not many fancy materials - one rectangular translucent elements, most elements rectangular and cylindrical. There are 2 Light sources in the model - the VU-Meters behind glass (imitated the light by placing one emitting rectangle, and one LED (i tried placing a LE-Circle inside a translucent sphere to avoid making the half-sphere light emitting). Given, I have lots of brushed aluminium elements with layered materials on them.

Now the scene was set up to twilight (say 17:00 hr, November, Europe), and the console tells me there were 360 light sources. Sounds to me like a lot, since I have one rectangle (-> 2 sources?) plus one 12-sectors circle (-> 12?) which totals for me well below 360, even if i made both sides emitting by accident. Now there is the sun from the scene, which produces whatever number of LE-surfaces... Is that a correct number? What should be "normal" rendering times for that?

Now my problem is, that I can't seem to get some decent effects in managable time. I work on a dell t3500, win7 64-bit, wich has Intel Xeon in it (8 cores, but kerkeythea gives me max. 4 to work with - i have some multithreading options off in BIOS, so guess that's alright), 12 GB ram and a Quadro NVS 295 card in it. I know that's not a speed monster, but... 8hrs rendering in 1280x1024 on preset 19 or 20 (MLT - i guess the slowe one was chosen) gives me just 130 passes???

Is that normal?

I provide the resulting image - please don't laugh, i don't even get to finer sculpting, adding bump maps for the faces and bitmaps, since I don't seem to get decent results in under 4hrs render time...



Can you please at least provide me information, how long should this kind of rendering take? Is the computer too sloppy even for such simple objects?

Thanks a bunch guys!