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  • Help with Lighting

    I'd like to create renderings that look like the attached photo. I could use some advice on lighting. Should I use an HDRI for GI lighting? A directional or point light for sun simulation? Whenever I combine GI and lights everything comes out very bright.
    Can I expect to have a generic lighting solution for this type of scene? I'd like to rotate the camera around and not re-adjust lighting, like a photographer getting different angles using existing sunlight. And even re-use these settings on other models.
    And, as in real life, I'd like to be able to look into the interior of the boat and see details without resetting lighting.
    I realize my materials will contribute a lot, but I can work on those.
    Your tips are appreciated. Please provide details of settings (like linear decay, inverse, position of point lights, radius, etc.)
    The land behind the boat is not important, I can do without that.
    I haven't gotten a material to look like the water, either. I've tried a mirror with a bump, but maybe I'm not setting it up correctly- I use a huge groundplane so maybe the bump map is being spread out too much?

    Thanks!


  • #2
    Help with Lighting

    Hi Craig,

    in the simpliest case I would set a blue colored environment and a wam colored directional light source. Important for a color mapping like in your example image: use the exponential mode. It's my favourit mode. Disable the clamp option. A little post work could help to get more contrast.
    Also you could use this map as standard environment:

    More suggestion for the usage of the map here


    It's an exterior scene without complex light bounces. So I would use LC+QMC and full adaptive sampling (Vlados universal method).

    For single shot I would set a background plane with a photo like the background of your example here. Water? Try to use a dark greenish plastic and a tiled bump. Send me an email and I will send you a nice bump map. Also, if you like to get a more realistic look you could rebuild the groundplane with much control points and use the random surface script from david rutten.

    -Micha
    www.simulacrum.de - visualization for designer and architects

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    • #3
      Help with Lighting

      Thanks Micha- I was hoping you might reply!
      So, for the simple scene with dir light, do you use GI? It seems like the light is very bright. How bright is the dir light compared to the GI?

      In your house example, you are using the posted image as GI environment lighting?

      I am getting some results with tiled bumps. I just had to play with the scale.

      Exponential seems so washed out compared to linear. I'd prefer not to post-process. Still use it? And what does "clamping" do, anyway?

      Maybe I can send you a scene sometime and see what you come up with.

      Thanks very much.

      Craig

      PS- Is your email the one on your website?

      Comment


      • #4
        Help with Lighting

        Originally posted by craiggorton
        Thanks Micha- I was hoping you might reply!
        So, for the simple scene with dir light, do you use GI? It seems like the light is very bright. How bright is the dir light compared to the GI?

        In your house example, you are using the posted image as GI environment lighting?
        I'm not sure, maybe I have used a color corrected version of the image. So the answer is not 100% yes. If you like to change the color mood, you can edit the map in photoshop per color gamma correct - for example set the blue graph lower.

        Try to set the intensity around 7. Best if you use the same value for GI and background. The light intensity could be 3 and the light color warm (249 201 132).

        Originally posted by craiggorton
        Exponential seems so washed out compared to linear. I'd prefer not to post-process. Still use it? And what does "clamping" do, anyway?
        Yes. But try to use the post process. I don't like post process too, but it seems to work. Look at my last update of my gallery. It dosn't look washed out or? In this scene I have try to get a little bit brighter bright areas and have set the bright multiplier at 1.2. I have the feeling, it increase the contrast. "Clamping" - I'm not sure how it work.

        Exponential - an example: if you render an interior with a light environment outside, you get the best light distributation in expontial mode only. The light in the room has a natural fallof (decay) from the window in the room. In linear mode, you don't get what you see in the real world. The window is to bright and the room to dark. Other example: if you like to try physical correct, than you should use the same intensity for GI and background. But in linear mode, the background and all your reflections will be burn out. In exponetial mode you get more.

        If you like test my example file here. You see, lighting and reflection are well balanced without much work.

        Originally posted by craiggorton
        PS- Is your email the one on your website?
        Yes.
        www.simulacrum.de - visualization for designer and architects

        Comment


        • #5
          Help with Lighting

          Hi, if your lighting looks to bright, it's because you make it too bright If you use GI skylight and directional light, you should decrease the intensity of the sky and direct. For example sky 0.3 and directional 0.7.

          If a photographer wants the interior to be bright, usually this results in the exterior to be too bright. An easy way to do this without adjusting any light is by increasing the dark and light multiplier of the linear color mapping. This simply multiplies all light, a bit like using a longer shutter time in real photography (or bigger diapragm opening).

          I'm also not keen on any of the color mapping modes, imo they're all hacks and results are not as realistic. The only good one is gamma mapping but this is hard to use right now since there is no gamma correction in the color selectors (so your materials will look washed out if you use gamma correction).

          Anyway you can get very good results with linear mapping too.
          Aversis 3D | Download High Quality HDRI Maps | Vray Tutorials | Free Texture Maps

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          • #6
            Help with Lighting

            Here's a testscene:
            http://www.aversis.be/vrayrhino/water.zip


            Use whatever bump map you like that looks like water, I choose the first one I could find...

            Fog color adjusts the darkness of the water (how much you can see trough)



            Aversis 3D | Download High Quality HDRI Maps | Vray Tutorials | Free Texture Maps

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            • #7
              Re: Help with Lighting

              I'm having trouble making this material work? Im trying to render the water along the shore of a site and all I see is white?

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