Recommended Settings

MidnightProphets

Hi, I try to search the forum before asking questions such as this but it's like finding a needle in a haystack for me so here goes.

What are some of the recommeded settings for rendering? I have a 3080 btw.

Texture Compression: I saw some tutorials on youtube and their opinions differ. One guy suggested 4000 medium threshold and 8000 high threshold. One suggested 1000 medium and 2000 high threshold and another one suggested to leave it as is.

Min Samples: It's set to 5 by default but would setting it to something like 200 or higher really help? I saw this from another tutorial, IT Roy I believe is his name.

Max Samples: My max samples are set to 5000 but I've heard artist say it doesn't matter much and to set it as low as 500, any thoughts on this as well?

Max Time: Finally, I've seen guys in tutorials crank this up all the way to it's limit but the rendering time has be much slower right? Like if you're planning on starting a Comic or Visual Novel wouldn't you want a consistent workflow system?

 

Any thoughts guys?

 

SofaCitizen

I think this is one of those things that really depends on what you are rendering, what you want to accomplish, personal taste and what your hardware is. This will be why you are getting different opinions from different people.

For me, I don't think I have ever really needed to mess with the progressive rendering settings at all. I have the texture compression set to 1024/2048 which is fine for my use - the only time I have really seen the need to tweak this was for a specific outfit that had a few strange blobs of colour along it (there was a semi-recent thread about this).

However, I tend to do "busy scenes" rather than "close-up portraits" and so perhaps my settings would suck for those kinds of renders. Also, I don't really care how long things take to render (within reason) since I can leave the PC doing that while I use my Mac for browsing/work or whatever and am not tied to any deadlines. If you were making a VN/comic then you would definitely have to be much more economical with the settings and maybe switch on the denoiser to speed up the renders and them crank out in a shorter space of time.

MidnightProphets

SofaCitizen said:

I think this is one of those things that really depends on what you are rendering, what you want to accomplish, personal taste and what your hardware is. This will be why you are getting different opinions from different people.

For me, I don't think I have ever really needed to mess with the progressive rendering settings at all. I have the texture compression set to 1024/2048 which is fine for my use - the only time I have really seen the need to tweak this was for a specific outfit that had a few strange blobs of colour along it (there was a semi-recent thread about this).

However, I tend to do "busy scenes" rather than "close-up portraits" and so perhaps my settings would suck for those kinds of renders. Also, I don't really care how long things take to render (within reason) since I can leave the PC doing that while I use my Mac for browsing/work or whatever and am not tied to any deadlines. If you were making a VN/comic then you would definitely have to be much more economical with the settings and maybe switch on the denoiser to speed up the renders and them crank out in a shorter space of time.

Thanks for the response, I'm going to keep experimenting to see what combination fits best. 

jkbrown2_630d37a382

I usually set Max Samples to 15000 as that seems to be the setting that most recommend. I set the converged radio to 98%. I don't change anything else.

TimberWolf

The rendering settings don't set the 'quality' of a render per se, apart from a couple of very specific options which I'll mention at the end.

What these settings do is determine how many iterations (samples or passes) the renderer makes through your scene before it considers it finished and stops. Consider two scenarios: The first is a dark, spooky room lit by a single light in the corner with volumetric fog and shiny reflective tiling on the walls. The second is simply a wooden stick on its own with a very simple texture. No scenery, nothing. Just a stick.

If I set the maximum number of samples to 500 the quality of the room render will be dreadful, full of noise and barely discernible. The stick will probably have looked great by about 50 samples. If I set the minimum number of samples to 250 it will do nothing to aid our room render and will waste time on the stick render.

So, in this case we're interested in how 'resolved' the image is, not really in how many samples it took to get there. To do this, set the maximum samples to a suitably high number (say 15000) and set the Rendering Converged Ratio to an amount that represents to you a finished image. I choose 99%, many would choose a little lower. On top of this we can set the Rendering Quality to a value higher than 1. This determines how many rays of light have to hit a pixel before iRay deems it actually converged and adds it to the converged ratio tally. Any number above 5 is probably a waste of time and I find 3 suits very high quality renders. Adjust as you see fit.

In this scenario our room would probably run for around 5000 iterations and our stick to maybe 100.

iRay will look at the settings you provide and stop *when the first condition is met*. If you set the Max Time to 5 seconds, the render will stop after 5 seconds regardless of how you set the convergence or any other parameter. You can, of course, turn all of this off and decide for yourself when the render is done by hitting the cancel button - set Rendering Quality Enable to Off and now it's down to you and your Mk.I Eyeball.

The parameters that do affect quality are Spectral Rendering and the Caustic Sampler / Guided Sampling under the Optimization section. It's a bit too involved to go into in any detail here and I'm going to simplify for speed, but caustics is basically the process of rendering light that passes through something specular (i.e. it reflects or refracts light) and then bounces onto a diffuse surface. Think light through a window striking a glass of whiskey with the reflection rendered on a table surface, the rippling light on the hull of a boat or the bottom of a swimming pool. Turning on the Caustic Sampler can give very good looking results compared to the standard renderer but at the cost of slower speed. Guided Sampling is something of a halfway house and faster but it's a little more complex than that. Generally worth turning on for indoor scenes as it may speed up rendering for a small cost in caustics quality.

Spectral Rendering uses the full spectrum of light for rendering, rather than just R,G and B. It can make organic objects look more realistic and alive (particularly skin) again at the cost of speed.

The final option that affects actual quality is the Texture Compression Threshold. iRay will not compress any texture under the Medium Threshold, applies medium compression to textures that are sized between the medium and high threshold, and high compression to any texture over the high threshold size. Turn these up for portrait close-ups (4096 and 8192 would work well, perhaps even higher) and turn them down for generic middle to long distance shots. This does not really appear to affect speed as such, only VRAM useage.