Mental Ray Q&A

Hi mental ray users and lovers,

Even though the Mental Ray Forum has disappeared recently from the web, we are here to help you with issues you might have with the Mental Ray plugins or the Standalone. Just ask your questions in the comments and we will try to come up with an answer in a new blog post.

For example, I wonder if and how you are using the GPU capabilities in Mental Ray, like the “GI Next” Global Illumination acceleration, or the fast GPU mode of Ambient Occlusion?

We are also interested in art work and renderings done with Mental Ray that we would love to highlight on this blog.

Happy to hear from you,


26 thoughts on “Mental Ray Q&A

  1. xrmm says:

    As an old user of mentalray, I would like to ask a digression. Mentalray was later acquired by Nvidia and the development was stopped. Then what was the original mentalray development department staff doing in Nvidia? I’m very interested. Does Nvidia have any plans to develop a new renderer? I recently saw that Nvidia is preparing a rendering engine called NVIDIA Omniverse. Was this software developed by the original mentalray department?

  2. As an old user of mentalray, I would like to ask a digression. Mentalray was later acquired by Nvidia and the development was stopped. Then what was the original mentalray development department staff doing in Nvidia? I’m very interested. Does Nvidia have any plans to develop a new renderer? I recently saw that Nvidia is preparing a rendering engine called NVIDIA Omniverse. Was this software developed by the original mentalray department?

  3. Parham Salamati says:

    Hey dear Steffen 🙂

    Thanks for all the efforts you make, and for keeping this place alive all this time, It’s been one of my favorite places to check out in the past couple of years.

    Mental Ray is still an active part of my vfx pipeline. Even though most of it’s usage is still on on Max 2016 for some reason, I’ve been using GPU Accelerated AO a lot and sometimes played with GI-Next as a hobby 🙂

    In a way of “Getting things done” perspective, I should say Mental Ray has become my “First To Go” solution for almost everything, unless I have a job Mental Ray could not handle due to compatibility and/or stopped development.

    FG is still my main focus (probably as I know how to handle it and troubleshoot), Legacy GI is still working for me (scene dependent), IP is a playground for me, no serious work though, and GI-Next is somewhat out of reach for me at the moment, again, just playing with it as a hobby.

    Standalone setup and trying to make use of GI-Next on a small farm sounds exciting though, and I think I’ll be trying that soon 😀

  4. Paul Marshall says:

    Hi Steffen, I use Mental ray to render images of Mars created from digital terrain maps that NASA release. I colour them and then set up a physical camera and let Mental work its magic. Here’s an example – there are lots more on my Flickr page.. the earlier ones were done with Scanline, until I discovered how to use Mental ray a bit more. Have only just discovered the Standalone render so will be playing with that later! Cheers Paul 🙂

    1. Steffen says:

      Wow, really cool. Didn’t know about these extreme details of the NASA data. The animation is super smooth (no flickering noticeable). And also very relaxing to watch. Well done. It feels like you could spot a Martian… 👽

      1. Paul Marshall says:

        Many thanks! The NASA images are taken with their super camera they call HIRISE, which is on the MRO Mars Reconnaissance orbiter. Its apparently the best space camera out there and can photograph at resolutions of 25cm per pixel, pretty cool from 200km above the Martian surface! They often take 2 shots to create stereo pairs and from that they generate a digital terrain map. They’re incredibly accurate as well.

        For any of the videos I totally recommend viewing them on youtube 4k on a smart TV. 🤓

      2. Tmel says:

        Hi Steffen. I came across this blog and wanted to ask you if it’s possible change the ray bias settings in 3DS Max Mental Ray for raytraced shadows?? The 3DS max manual says that Mental Ray “disregards” the ray bias settings, so there is no raytraced shadow bias at all with the mental ray renderer- which can lead to some stubborn self shadowing artifacts. How do I change this??

      3. Steffen says:

        There is mentalray „ray offset“ setting to tune self-shadowing for coarse tessellations. I need to check if that can be used inside 3ds Max… But typically, increasing the quality of tessellation helps reducing the problem.

      4. Steffen says:

        I was searching the mental ray UI in 3dsMax for any exposure of the „ray offset“ control on geometry or shaders without success, which seem to confirm what I was suspecting: it has never been supported there, in contrast to Maya for ex. Admittedly, it was kind of an advanced feature anyway to directly tune the raytracing engine rather than fixing the input geometry. What exactly is the problem you see?

  5. It would be amazing to have access to a license. We use mental ray for simple contour rendering. With the subscription model that Autodesk utilizes, we lost our access to Maya 2016 (and with it Mental Ray). Now we are stuck with having to go to pay full prices for Arnold to access the smallest of features. And its quite slow.

    It was exciting to see that we could get Mental Ray in 2018 but because of the licensing, cant seem to get it to batch render multiple render layers.

    Would LOVE to purchase a license still.

    1. Steffen says:

      Well, you can get a license for batch rendering on a specific computer. Just send a request to arc-licensing(at) to provide the necessary info about your machine. Best, Steffen

  6. Hi all, I have some problems using mental ray on 3ds max 2018 with gpu. I tried Gi next with gpu on 3 separate pc and none of them seems to work. i can render with cpu ang GI next on but if i activate the gpu in hardware resources 3ds max wont render. it will stop with the bucket on and the green bar saying rendering… I tried using game driver and creative studio studio driver and also default system driver for gpu and I tried GTX 770 – GTX 1060 – RTX 2070 none of them works. I have the 2018.4 update on 3ds max and the 1.0 of mental ray. any help would be apprecieted

    1. Steffen says:

      Sounds strange to me. The GI Next GPU implementation was based on CUDA 9 and related generation of graphics cards, before RTX came along. But generally, more recent cards should work. Do you have a driver version number for me?

      1. Steffen says:

        I cannot reproduce myself with 3ds Max 2018.4, it works fine with GI Next GPU. I’m using an older driver though but can’t imagine that to be the problem. Do you use other CUDA applications on your machines that work with issues? Do you have any kind of message log that shows the errors?

  7. Sam says:

    Hi all, I have problems using mental ray on 3ds max 2018 with RTX GPU.

    I recently went from a GTX Titan X to a RTX 2080 and i can’t render anything since the change.
    I’m using the same Driver for both renders and when i put the Titan back in my machine it works.
    Would Mental Ray be incompatible with newer RTX cards ?


    1. Steffen says:

      You mean mentalray stops rendering completely, or just the GPU acceleration does not work? MR does not require a GPU, and if a GPU is in your system but not supported by MR it should fall back to CPU only. Do you use the free version of the plug-in or an older licensed version?

      1. Tmel says:

        Hi, again. I solved the problem. it seems like mental ray materials are less susceptible to artifacts than 3ds max ones are in mental ray. For instance, bump mapping causes terrible artifacts with 3dsmax materials but mental ray of ones are abscent of them. Never found a solution for artifacts caused by the geometry itself though. It seems like a huge oversight on MI’s part considering even 3DS Studio DOS had ray bias settings since 1992-93. Thanks anyway.

      2. Steffen says:

        Glad to hear it works for you. BTW, I guess you’re referring to „shadow bias“ which was a common setting for shadowmaps at the time. I think it turned into a “ray bias” in more recent versions still related to just shadows. Anyways, bump mapping is another “trick” that may distort the geometry in non-physical ways which was Ok for scanline renderer but it’s problematic for ray tracers.

  8. Hi Steffen, i’m using the free version of the plugin and it seems like it doesn’t fallback to the CPU in my case. It stays at the Initializing phase and no rendering is being done.

  9. JASON says:

    Hi Steffen
    mental ray is my favorite render
    it is very fast and convenient
    but there is a question…

    render elements add mr Ambient Occlusion (this is the fastest AO. I have never seen. I guess it is accelerated by the gpu)
    render will crash in new nvidia drivers

    I am use 3ds max 2017
    hope you can help me
    thank you.

    1. Steffen says:

      I guess you’re not using the NVIDIA version of the mental ray plugin but the regular one that’s coming with the 2017 edition of 3ds Max? If that’s the case I would suggest to try the latest version you can download here on this blog.

      1. Thanks for your reply
        I use 3ds max 2018 mr Ambient Occlusion it still crash in new nvidia drivers

        but Install nvidia drivers 452.06
        it working

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