Iray Rendering Quality Setting +/-

Scavenger

Looking for some basic info on the Rendering quality setting slider.

It defualts to 1...but goes both up and down into the negative......What's better, what's worse..what happens if you go negative?

Richard Haseltine

I can't recall the exact details, but it controls the level at which a pixel is regarded as converged - it is roughly linear (doubling doubles render time). I don't know what will happen with a negative value.

nonesuch00

Yeah, I just changed mine from Quality Level 5 which is very slow to converge to Quality Level 1 and immediately DAZ Studio on the render that is already running restarted some sort of calculations in my render but did not restart the entire render. It should now actually have a change to render within 3 days.

dastardlydoug

Hi out there.

I downloaded some free hdri domes and backdrops.

does anyone know which folder they are supposed to go into

thankyou in advance

Tont

KindredArts

dastardlydoug said:

Hi out there.

I downloaded some free hdri domes and backdrops.

does anyone know which folder they are supposed to go into

thankyou in advance

Tont

I made a folder in my library/runtime/textures and called it "HDRIs". That's where i keep all of the random Hdri's i pick up online. I also save them as a render preset when they are set up in scene so i can re-load them at any point. Hope this helps.

Richard Haseltine

dastardlydoug said:

Hi out there.

I downloaded some free hdri domes and backdrops.

does anyone know which folder they are supposed to go into

thankyou in advance

Tont

If they are just images then any folder you like - \Runtime\Textures\Some folder in a content directory would ensure that relative paths were used when saving (so the files would still load if moved to a different machine) but the main thing is to put them where you can find them when loading via the Browse command from an image selection menu.

Tobor

The Rendering Quality setting controls a threshold of when Iray will consider a pixel "converged." Convergence is part of the iterative rendering process Iray uses. The more rays that strike a pixel, the faster the convergence, and the quicer the render is done. You can set a "stop-at" value of when iray considers the bulk of the pixels converged (default is 95%), but Rendering Quality eases or restricts the interpretation of when that convergence takes place.

A value of 1 is the normal setting. Going higher increases the threshold and Iray takes proportionally longer -- 2 means about 2X longer to render, 4 means another doubling, and so on.

Values under 1 reduces the threshold demand, and pixels are deemed converged when there may be objectionable artifacts. The ideas is to "tune" the setting to match your particular scene. It can be helpful in animations, where to go through the frames more quickly, you might want to set a lower convergence threshold but keep the other stop-at values alone.

Scavenger

but what is negative? mine defualts at 1, but what's sub zero...

AndyS

If you're brave - try it! 

Tobor

Scavenger said:

but what is negative? mine defualts at 1, but what's sub zero...

I find this stuff out by trying it. I don't think I'd personally have a need for a <0 threshold, but you're welcome to experiment, and it would take very little time to see what happens.

nonesuch00

For the OP...

OK, I usually render at 4K in iRay via CPU render and Quality Settings set at 5. At those settings the renders time out after 3 days (I maxed to limited seconds out) at less than 10% completed and usually about 4%.

For the past 2 days 21 hours 52 minutes and 46 seconds I have been rendering with the Quality Setting set to 1 and it's at 1831 iRay iterations and 54% converged. So I recond at the time out on 3 days I will be about 60% converged and 2000 iterations.

These numbers are for well lit indoor scenes, eg, for the render I am running now it is the containment corridor.

azraeldamien

I run two titan x graphics cards and i find that the images will come out roughly the same. save a crap load of time and set the quality at one and you can just do post work in photoshop for any artifacts that may remain

Novica

azraeldamien said:

I run two titan x graphics cards and i find that the images will come out roughly the same. save a crap load of time and set the quality at one and you can just do post work in photoshop for any artifacts that may remain

+1    I did experiments and the quality/ difference was negligible. The most I would do is a setting of two, but even then, good lighting equalizes the differences for using the default, vs a 2 setting. All my renders are ones. 

jbrendan.k_3325c4b564

Tobor said:

The Rendering Quality setting controls a threshold of when Iray will consider a pixel "converged." Convergence is part of the iterative rendering process Iray uses. The more rays that strike a pixel, the faster the convergence, and the quicer the render is done. You can set a "stop-at" value of when iray considers the bulk of the pixels converged (default is 95%), but Rendering Quality eases or restricts the interpretation of when that convergence takes place.

A value of 1 is the normal setting. Going higher increases the threshold and Iray takes proportionally longer -- 2 means about 2X longer to render, 4 means another doubling, and so on.

There were absolutely no helpful answers to the query of this thread. Tobor mentions "objectionable artifacts". I wonder if he is talking about products for Daz that can be rendered, or in many cases not completely rendered.

 

Values under 1 reduces the threshold demand, and pixels are deemed converged when there may be objectionable artifacts. The ideas is to "tune" the setting to match your particular scene. It can be helpful in animations, where to go through the frames more quickly, you might want to set a lower convergence threshold but keep the other stop-at values alone.

jbrendan.k_3325c4b564

There were absolutely no helpful answers to the query of this thread. Tobor mentions "objectionable artifacts". I wonder if he is talking about products for Daz that can be rendered, or in many cases not completely rendered

onix

According to Richard, This setting is a duplicate of the "convergence ratio"

 

Nothing worth using unless you are rendering animation for single images  it is easier to visually decide if it is finished or not or just leave rendering for an undefined amount of time if you are leaving the computer

FSMCDesigns

azraeldamien said:

I run two titan x graphics cards and i find that the images will come out roughly the same. save a crap load of time and set the quality at one and you can just do post work in photoshop for any artifacts that may remain

 Man if Ihad two titan cards installed, I would expect to never have to do any postwork, ever, LOL

Richard Haseltine

onix said:

According to Richard, This setting is a duplicate of the "convergence ratio"

Convergence Ratio sets how many pixels must be deemded converged, the quaility controls just how converged they must be to count.

 

Nothing worth using unless you are rendering animation for single images  it is easier to visually decide if it is finished or not or just leave rendering for an undefined amount of time if you are leaving the computer