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zebus_0 polycounter lvl 7
I'm working on the tutorial via Digital Tutors of the Photorealistic bedroom
Here: http://www.digitaltutors.com/tutorial/1083-Creating-a-Photorealistic-Bedroom-in-3ds-Max

I'm in the home stretch, trying to set up renders but I'm running into more problems. Made threads about this tutorial before. Like a lot of tutorials it falls completely flat when it comes to "this is some problems you might encounter, here's what it could be". I'm still learning 3ds max, have never set up a render, let alone in Vray.
Anyway, the problem is that my renders were first rending flat black. I assumed that I may have some issues with my physical vray camera, so I adjusted the settings and now my renders are blowing out white. Attaching pics of my camera and sun settings. It's also telling me I can't render unless I select a valid object, I didn't think selection of objects was necessary for rendering the scene.
Any ideas?

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  • .Wiki
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    .Wiki polycounter lvl 8
    If its blown out you need to change the f-number (higher value means = less light reaches the film/sensor) and lower the shutter speed (also less light).
  • xXm0RpH3usXx
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    xXm0RpH3usXx polycounter lvl 13
    Did you check your max internal Gamma settings?
  • bacteria
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    try turn off exposure on your camera
  • Rombo
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    Well, that means your Vray Camera Exposure is too short or too long for the shot you're looking for.
    This viscorbel link will give you a pretty good idea how things work, let me know if you run into any problems, I might be able to help out.

    http://viscorbel.com/vray-physical-camera-tutorial/

    For the Standard max cameras, you should manually set your intensities to all lights in order to get a balanced output. For the Vray Sun, for example, when using a standard max camera, I always set for starters the intensity to 0.02, and I work from there...

    Hope it helps, cheers!
  • zebus_0
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    zebus_0 polycounter lvl 7
    How do I check the gamma settings? I adjusted the F-Number and removed exposure and I am now getting a still, but with a weird....flaking? effect. I'm not entirely sure what it is.
  • zebus_0
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    zebus_0 polycounter lvl 7
    Also, here are some uploads of my render settings at present. I have tried to take down the DMI because it was suggested that may be it by someone else. Also worth mentioning that in the preview of the render and the actual image there is a pretty wide difference as far as lightness/color saturation. There are just so many things it could be between camera/lights/render settings/color/ect I'm having a really hard time narrowing down what this could be.
  • .Wiki
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    .Wiki polycounter lvl 8
    Looks like you only use one GI bounce. Try to use a combination of Irradiance Map AND Light Cache. You would also need to adjust your samplingvalues. Your renders won´t look great out of the box. You need to adjust these settings.

    Also check if gamma is enabled/disabled. You should always render with gamma 2.2 enabled. But if you use it, check your import settings for textures. Otherwise they will look washed out if they are not in linear space.

    http://www.aversis.be/tutorials/vray/vray-20-gamma-linear-workflow_01.htm or this http://renderstuff.com/using-gamma-2-2-cg-tutorial/
  • Roxxor
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    Roxxor polycounter lvl 13
    The problem I see is that you are rendering with Vray RT. That is a realtime renderer that is used to check overall lighting, but I don't think it has a good overall solution. In the common tab, under "renderer" make sure you have Vray 2.30 selected as the production renderer, and set Vray RT as the activeshade.

    THEN try setting your sun to intensity: .009
    And your camera settings to:
    white balance - neutral
    f-number - 4
    shutter speed - 125
    film speed - 750

    If you want to raise your exposure, simply increase your film speed (ISO) but leave the other two values alone. This will give you more control since it simplifies the variables. The f number and shutter speed affect depth of field and motion blur respectively, if you aren't using those effects, you should set them to neutral values like above.
    In terms of the render settings, after you set the normal Vray renderer to the production renderer, take a look at the Aversis link posted above, that guy has pretty good test settings. Otherwise, when I get to the office later I can take some screenshots of the settings I use.
  • zebus_0
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    zebus_0 polycounter lvl 7
    Gonna try these suggestions, I work on the road right now doing something different and I had to leave my PC before I could fix it, sadly, so I'm going to have to rig up Max on my travel laptop (.....eesh) and see if I can get any results that way.
  • zebus_0
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    zebus_0 polycounter lvl 7
    I apologize for this thread stagnating without it moving, but as I work traveling and can't get to my workstation often this is how it has to be. I've taken the advice given, adjusted the Camera settings and I was able to switch to Vray instead of RT (DOH!). I'm getting a much better image, but still having some issues. First off is that it's REALLY dark. I figured the obvious, turn up the light on the sun but that doesn't seem to be helping. I have two plane lights in the windows but they don't' seem to be having an effect on the scene one way or the other.
    I'm also seeing a bit of pixelation on the floor still from the bump. Main question is how to get the lighting turned up. Also I'm not sure if it's an effect from Vray or if it's on the camera but it looks like it has a Depth of Field on it and I don't have it turned on anywhere that i know of but the scene overall just seems 'fuzzy'.
    I know these are all pretty novice questions but like I said, I'm new to rendering in Vray and in 3ds in general. I know I could google tutorials all day for it but I really don't learn well that way at all. Pic attached of current render.
  • Nox
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    Nox polycounter lvl 5
    For a novice it's better to avoid Vray Physical Camera. If you want to use Vray Sun/Sky then open Enviroment, set Exposure Control to VRayExoposureControl and mode to From EV parameter. This way you will have only one value to control overall lightness of the scene.
  • Dave Jr
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    Dave Jr polycounter lvl 9
    Ok, just a few quick words of advice... I work with Vray on a daily basis in a studio and producing images similar to these.. probably much more realistic to be honest...

    We have a common light setup of

    Vray dome light
    Vrome directedlight 1 or 2 coming from an open lightsource i.e windows etc..
    Vray spotlights for lamps etc

    We use bounceboards to flag certain areas off and increase bounces to lighten specific objects..

    Our F number is always 7-8 NEVER EVER 3...try raising that and post your result... ill advise further when I've seen a render with a higher Fstop :)
  • zebus_0
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    zebus_0 polycounter lvl 7
    Took given advice, adjusted the F Stop to 7 in the first image. The second image is me going back and re-doing the tutorial to make sure I had all the same settings. Both images however, before and after adjusting the f number are about the same. Now it seems the problem is I'm way too bright. What I don't get is that the plane helper lights in the windows don't seem to be doing anything for or against me regardless of setting changes. I've also got the weird dot artifacts back, part of the numbers on the sun? I don't take anything personal, I'm sure if you're a professional (Dave) that it's more realistic lol, you could say it's sh!t and I'd still ask how to fix it, here to learn. (Just glad people here are so receptive to those of us like me who are stumbling). What I don't get is that I've followed every step this guy has taken, have all the same settings, yet I have a radically different result as far as the first render tests are going.
  • Dave Jr
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    Dave Jr polycounter lvl 9
    zebus_0 wrote: »
    Took given advice, adjusted the F Stop to 7 in the first image. The second image is me going back and re-doing the tutorial to make sure I had all the same settings. Both images however, before and after adjusting the f number are about the same. Now it seems the problem is I'm way too bright. What I don't get is that the plane helper lights in the windows don't seem to be doing anything for or against me regardless of setting changes. I've also got the weird dot artifacts back, part of the numbers on the sun? I don't take anything personal, I'm sure if you're a professional (Dave) that it's more realistic lol, you could say it's sh!t and I'd still ask how to fix it, here to learn. (Just glad people here are so receptive to those of us like me who are stumbling). What I don't get is that I've followed every step this guy has taken, have all the same settings, yet I have a radically different result as far as the first render tests are going.

    Can you upload your scene somewhere so i can dive in and have a look?
  • zebus_0
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    zebus_0 polycounter lvl 7
    Love to, sent you a PM about how to best wrap it up.
  • Dave Jr
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    Dave Jr polycounter lvl 9
    Ok,

    so myself and a colleague played around with the scene, took us a little whilst to go through the settings and get to know what you were trying to achieve; but after a few tweaks we got this:

    X5cWotW.jpg

    I know its not EXACTLY the same as the concept; the only thing you need to do now to try and achieve the same result is to adjust the Vray Sun intensity, and to move its target in a different direction to achieve the silohuette of the windowframe on the wall. The worst case scenario if this doesn't change it too much would be to just adjust your F Number by 1 or 2 - nothing more :)

    0. The scene was sooo bright because the Vray Sun was too high a setting - we ended up going to 0.001 for this lighting I believe...


    1. The blue dots were caused by low subdivisions given off by your Vray Sun; this was then reduced further as it hit your glass window and finally entered the room to give bounced light. This has been increased to 32 from 8.


    2. The wall material was way way too bright; it again was increasing the amount of "white" you were seeing; especailly when the light hit it to become brighter and burn out.

    3. The floor texture again was white, it should be grey - again this was adjusted.

    4. You had some crazy crazy exposure settings in the environment window; some were relating to mental ray even when you were using VRAY so this again was fixed.

    5. After several tests to get the best result we decided to to actually hide the glass. If you want to keep its glass reflections we made(despite this being blown out in the concept) you can bring it back and go to object propreties - and just decrease the visibility to let light through yet still keep a small amount of reflection.

    6. Changed the glass reflection material to again 32 subdivs

    I'm not saying these are perfect and the most accurate way of fixing things; as we don't usually use the brute force technique, we use the radiance map but it was a fix all the same.

    Cheers and hope it helps - any questions just pm me :)

    EDIT: As a final note; you might want to define some of those materials in scene a little more. I wanted to change them myself but wasn't allow to add from your studio Vray library :(
  • zebus_0
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    zebus_0 polycounter lvl 7
  • Dave Jr
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    Dave Jr polycounter lvl 9
    zebus_0 wrote: »
    Sending a PM.

    Never got a PM, but glad I could help :)
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