Animation - Store with irradiance map?

[Morne]

Hi all

So if I have an animation with moving objects and have lots of VRayLights in the scene, would I use the "Store with irradiance map" option?
Why or why not?

[Morne]

anybody at all?

[themaxxer]

the whole animation thing is not clear at all for me too.
someone says that, someone something other.

I think it depends how you pre-render the IR map. if you render each frame with the preset "animation" then it could work.

but I don't really know. I can recommend the vray complete guide for further information.

best regards
themaxxer

[super gnu]

the "store with irradiance map" option in the vray material is very useful if you have small moving objects in the scene. (i.e. people) just hide the moving elements, calculate fixed imap as if it was a flythrough, unhide moving objects (which have "use irradiance... unticked in their materials.) set imap subdivs to control the brute force subdivs used for those materials. (changing that wont affect imap as its already calculated) then render.. the scene will have precalc gi, but the moving objects will have brute force GI. add some AO and you get back the contact shadows for the moving objects. obviously not totally realistic but works well in a lot of cases.

i use this trick on almost every big animation i work on.

[Morne]

ok so the "store with irradiance map" in the light setting doesnt work for me. Much worse flickering around the lights when this option is ticked (and reflect unticked)

I didnt touch this setting in the materials and it is at its default value in the materials

[super gnu]

ahh.. sorry i was confused. happens often. i was thinking of "use irradiance map" in the vray material.. hehe. store with irradiance map just turns vray lights into the equivalent of geometry with a vray light material on it. therefore detail and quality are solely controlled by the imap settings.

so you can use a lot more lightsources with it ticked, and the rendering phase will be faster, but shadow quality will be limited by the imap detail.

with regards to animated scenes with moving geometry, its probably better to keep it unticked, as that way your direct lighting will be accurate and flicker free for the moving objects and their shadows, and the flickering and glitches will be restricted to the gi portion of the lighting. with it ticked you place complete reliance on the imap for all your lighting.

[Morne]

ok so then for my situation its best for the VRAYLIGHT to have "store with irradiance map" OFF and also switch OFF "reflective" and "specular?
Or would you leave on both or either or "reflective"/"specular"?

Also I have a couple of standard spot lights in my scene together with the vraylights. For the standard lights, would I also switch off "specular"?

[super gnu]

mm im not sure why you would turn off reflective -and- specular for vray lights.. i usually either turn off specular, or do it in the materials, then use reflectivity to give true specular reflections, having them both on tends to blow things out unexpectedly.

wrt the standard lights, the only way youll get highlights from them is to use the specular effect, as they have no physical dimensions, so cannot show up in reflections.

having said that, if youre doing concrete, or some subtly reflective material, its sometimes enough to keep reflections switched off in the material, and use the specular effect from the scene lights to give you a feel of a reflective surface. however to be honest i usually do it all with reflections, as it just looks nicer!

those settings (specular and reflection) shouldnt really be any different for animation or still images.

[GLASS-CANVAS]

For animations with moving objects and/or lights we always use the Animation (prepass) and Animation (rendering) method, and it generally gives very little flickering and accurate GI. It really comes into it's own if you have access to a renderfarm as you can spread the frames across multiple machines.

[super gnu]

yes that method does give good results in a lot of situations, but on tough scenes (interiors with small windows etc) it can be quite hard to get a clean result.. also ive found if you use very detailed irradiance maps, the rendering penalty of using multiple imaps for each frame can -sometimes- push it close to the brute force rendertimes. this can be alleviated somewhat by reducing the "interp. samples" setting.

all depends on the scene really. i guess if there was one method that always worked, there would be a lot less posts on the forums!

sacrilege i know, but when i have scenes with all the geometry moving, ill sometimes turn to... MR. FG perframe give some pretty quick, clean results.

[Morne]

For animations with moving objects and/or lights we always use the Animation (prepass) and Animation (rendering) method, and it generally gives very little flickering and accurate GI. It really comes into it's own if you have access to a renderfarm as you can spread the frames across multiple machines.

This is what I am doing. My minor flicker can probably be attributed to the fact that I'm using the "very low" preset of the IRmap (with 50 hsp samples and 40 interp samples). This is an exterior night scene. I can't push the IR settings up any further as I'm already getting 1.5 hours per frame as it is now. And that's on a 2600K with 16GB ram. For the life of me I can't understand why it's rendering so long. I've been struggling with this for more than a month now trying to bring down render times and get an "acceptable quality". So far no luck. Im rendering 720p and trying to get it in the 30 min per frame region. But seems this is just not going to happen

[super gnu]

does it render faster when you render a straight test frame using a single imap?

if so, then thats the problem that bugs me about animation mode. the overhead of using multiple imaps is often surprisingly high.