Rendering Agony

[gazzamataz]

This little problem is proving to be a right headache... Have a look at the frame below and notice the rendering time for the anti-aliasing. Over one hour for pass1 and over two hours for pass2 - this seems rediculous considering the frame before only took 8 minutes!

 

The scene is using particles and volumetric lights but why the sudden jump in render times from one frame to the other???

 

[ddustin]

Gazz,

I had seen that on a recent render as well, there was one frame that no matter what machine I put it on, would render for about 4 hours.

 

I just let it run on one of the render slaves till it was done cooking.

 

Never did issolate the cause.

 

David

[Paul Forwood]

I have seen this recently too.

First frame of a 4-pass render took less than a minute and then the second pass would have gone on forever. I left it for about half an hour and A:M predicted a render time of more than a day for the second pass. Can't recall the exact times at the moment but the issue seemed to be related to corrupted volumetric lights.

 

Try deleting your volumetric lights, save, reload and then render. (A reboot might be advisable too, to be sure that everything is starting up clean). If that works alright create new lights and add them in one at a time with a test render of a few frames after each new light is added.

[3DArtZ]

I'd drop the particles and use sprites....

[Eric2575]

I had the same problem and Paul's answer solved mine too, one of the volumetric lights was causing it for some reason.

 

Deleted the light, created a new one just like to old, and voila', render times reduced dramatically. The way I got to the bottom of it was to turn everything but one object off, then render. If it rendered fine, then turn the next object on, etc, until you turned something on that would cause your render times to get stuck. That would be your culprit, and in my project, it happened to be the volumetric light.

[gazzamataz]

Thanks for the help Hashers - much appreciated.

 

I have experienced the single frame taking ages to render before, but in this case it was several frames so just dropping that frame workaround is out of the window...

 

I have also experienced the rogue light scenario and have already replaced the volumetric lights in this project, so it wasn't that phenonmenon causing the problem either.

 

I then re-rendered this section without sprites and particles and it worked perfect so that seems to be the problem. However I am loathe to replace the sprites with particles since I would have to rerender other sections and probably develop more problems...

 

Banging my head off the wall I just want ot get this rendered why does it have to go errant on me!!!

 

It really is annoying that it does this since, as I originally said, the previous few frames worked fine. It might be that specular highlight on the bell in the background that has sparked it off.