Do iterations decrease with the time the computer has been running?

RenderPretender

Does the number of iterations decrease with the time the computer has been running or what else it is doing, or is it completely independent of that, and more dependent on factors like light changes, scene content, and camera angle? I seem to notice that one scene where I'm shooting more up at the subject has less iterations than others in the same set with identical content.

Sevrin

If you are using the same resources for Daz, i.e., CPU and GPU, depending on what you are using for rendering, for other things, those resources will be less available to Daz and the render engine will run more slowly.

RenderPretender

Sevrin said:

If you are using the same resources for Daz, i.e., CPU and GPU, depending on what you are using for rendering, for other things, those resources will be less available to Daz and the render engine will run more slowly.

So, since I'm rendering for a finite time per panel, I might possibly see less iterations for a specific panel. Thank you. Would I just need to restart DAZ, or the whole computer?

Sevrin

masi3vee said:

Sevrin said:

If you are using the same resources for Daz, i.e., CPU and GPU, depending on what you are using for rendering, for other things, those resources will be less available to Daz and the render engine will run more slowly.

So, since I'm rendering for a finite time per panel, I might possibly see less iterations for a specific panel. Thank you. Would I just need to restart DAZ, or the whole computer?

It's more a matter of not doing anything else strenuous with that computer while rendering.  Web browsing should be okay, but gaming would not.  You can also set a a limit to the number of iterations, rather than the number of seconds, depending on whether quality or speed is more important to you.

RenderPretender

Sevrin said:

masi3vee said:

Sevrin said:

If you are using the same resources for Daz, i.e., CPU and GPU, depending on what you are using for rendering, for other things, those resources will be less available to Daz and the render engine will run more slowly.

So, since I'm rendering for a finite time per panel, I might possibly see less iterations for a specific panel. Thank you. Would I just need to restart DAZ, or the whole computer?

It's more a matter of not doing anything else strenuous with that computer while rendering.  Web browsing should be okay, but gaming would not.  You can also set a a limit to the number of iterations, rather than the number of seconds, depending on whether quality or speed is more important to you.

For the kind of work I do, I generally render for 900 seconds with the optimization set to Memory, with generally very satisfactory results. I'll try that scene again after a DAZ restert and leave the machine alone as an experiment.

kenshaw011267

900 seconds (15 minutes) could be short depending on the scene. You're going to need to examine each scene.

I get wanting to maintain a production workflow but it's going to be hard to be that rigid and get good results.

RenderPretender

kenshaw011267 said:

900 seconds (15 minutes) could be short depending on the scene. You're going to need to examine each scene.

I get wanting to maintain a production workflow but it's going to be hard to be that rigid and get good results.

I reloaded that scene and re-rendered it, leaving the machine alone, and there was an immense improvement, even with reverting to the original tone mapping. Might be something I'll just have to keep in mind.

SpottedKitty

Don't forget there are three "stop conditions" that you can set in the Render Settings>Progressive Rendering pane.

1. Max Samples; default is 5000. This measures how many times the render engine chugs through the render data.
2. Max Time, measured in seconds, as you've found out
3. Converged Ratio; default of 95%. This is the complicated one, it's a measure of how much each pixel in the render changes between one sample and the next; the change gets smaller as the render chugs along. Note that this default value is really for quick test renders; when I want a final render, I usually bump this up to 99.5% — you can get as close to 100% as you want, but this value should be below 100.
4. Yes, the fourth of three and IMHO the most important; "Does this render look good right now?". I usually stop the render manually if it looks good and the render is nowhere near hitting any of the stops.

There's also a Render Quality setting, which I usually leave at 1 unless I'm doing a final render that I want to come out really sharply focussed and crisp. A value of 4 works nicely, although it does slow the render a bit.

RenderPretender

SpottedKitty said:

Don't forget there are three "stop conditions" that you can set in the Render Settings>Progressive Rendering pane.

1. Max Samples; default is 5000. This measures how many times the render engine chugs through the render data.
2. Max Time, measured in seconds, as you've found out
3. Converged Ratio; default of 95%. This is the complicated one, it's a measure of how much each pixel in the render changes between one sample and the next; the change gets smaller as the render chugs along. Note that this default value is really for quick test renders; when I want a final render, I usually bump this up to 99.5% — you can get as close to 100% as you want, but this value should be below 100.
4. Yes, the fourth of three and IMHO the most important; "Does this render look good right now?". I usually stop the render manually if it looks good and the render is nowhere near hitting any of the stops.

There's also a Render Quality setting, which I usually leave at 1 unless I'm doing a final render that I want to come out really sharply focussed and crisp. A value of 4 works nicely, although it does slow the render a bit.

I turn Render Quality Off, set optimization for Memory, and leave Max Samples at the default of 5000. The variable for me seems to be whether I use the Aux Viewport to preview. I rendered the subject scene for 900 seconds and it ran 17 iterations. After closing DAZ and re-atarting it, the same scene ran 83 iterations in 900 seconds, with almost no noise, which I can clean up in post with Topaz Denoiser AI, a lifesaver. Re-starting DAZ is a bit of a pain, but it takes less time than the 15 minutes consumed by rendering a noisy scene due to low memory.