Rendering and iterations

alex_bb8aa5da

I know that there is no answer to "how long does a render take" because it is all computer and scene dependent. However, do you guys have rule of thumb on the number of iterations you like to let iray run for before letting it go much longer has little worthwile effect?  I am presuming (very very possibly incorrectly) that while different computers will take a different amount of time to render 100 iterations of the same image, the two 100-iteration images will be similar.

Illidanstorm

Around 2000. For interriours 5000

Eagle99

You might want to take a look here:

https://www.daz3d.com/forums/discussion/53771/iray-starter-scene-post-your-benchmarks/p1

It tells you something about rendering times on different configurations.

 

As far as I know there is no rule of thumb for the for the amount of iteration before the image quality doesn't get any better.

Rendering times and the number of iterations needed depends very much on the light sources in Iray and of course the complexity of your scene and the rendering resolution.

Environment maps act like a giant multi light source, so they have a big impact on time and quality as well of course.

In general you can say, the more sources, the longer one iteration takes.

The darker the image (or areas of the image), the more grainy areas you might have that take a higer number of iteration before grain goes away (if it does at all).

On a standard scene in a regular resultion like FullHD, with one or two figues and a standard light set of 3 to 5 lights, not to dark, I usually see not much difference after 4000 iteration or so. So I let it run maybe 5000 or 6000. (I always turn off render quality and just set the max iterations to the number I like)

But I heard numbers of  multiple 10000 iteration others use for their renders. I didn't saw a need for that for my renders so far, but on very complex scenes that might be necessary.

You can always set the number very high and just stop the render when you don't see any more improvements and save your image.

And finally, yes, 100 are 100 iteration, no matter how long they took an which computer, CPU or GPU... result is the same.

Kind regards, Eagle99

 

 

alex_bb8aa5da

Guys, thank you!! I've been turning off after 500-700 iterations, thinking that's as good as it gets.  now I know to try running it longer and see if it doesn't get better still!!