What should Shadow Blur Radius be for a bright, sunny day?

  • @anomalaus I have tried using an area light like a reflective/bounce card. It's gotta be used tastefully or it'll ruing the lighting. Too much and it just looks like photo-flash with a cheap camera. OTOH if that is the loom you are after then that's what you do.

  • Poser Ambassadors

    Cheap fill flash would give harder shadows than that as the light source is physically small. An area light would be equivalent to a softbox which is directly emitting light from a flash unit, rather than a reflector which is passively bouncing it back. Reflectors are used as a more subtle alternative to fill flash as it can easily be too harsh. I'd try using a polygon mesh (like the simple square primitive) with a white (or maybe gold) diffuse material.

    I made a demo a while ago on bounced/indirect light, thought I might as well post it. This scene is using a single infinite light at 100% intensity plus the Blackout material applied to the default Ground (the Construct) -


    Exactly the same setup with one change - the White material has been applied to the Ground -0_1525904953321_demo2-white.jpg

    The materials are in the default installation in Materials/The Construct. They are diffuse colour only - the environment is not emitting light at all. The parts of the scene receiving direct light from the infinite light don't change, but the rest of the scene is transformed as the areas that are lit indirectly by bounced light pick up colour & value from the environment. Superfly does real ray traced reflections all the time which is why it must have a 360 degree enclosed rendering environment; that environment could be a simple diffuse colour, or an HDRI pano, or a JPG, or a complete 3d environment. It depends on what is required but whatever it is it will have a massive influence on the scene & is as important as any direct lighting.

  • With Infinite light and shadow blur radius I prefer to use 1-2 or around this figure,but sometimes I use higher number for indoor renders where I use high numbers like 10 and more and agree with guys who use extra fill lights,I use large or larger area lights which are further from figure like in this render,I used infinite light with low intensity and two area lights with 65-75%

    Edited in Photoshop,edited only curves with Camera RAW filter and render has been exported as OpenEXR

    alt text

    Hope this helps


  • A quick reference from the real world - I find that that can sometimes help clarify things.

    Here's thee shadow of a plant (leaves about 1m from the ground) on a gloriously tropically sunny day.

    Top photo - no clouds in front of the sun, but possibly a slight overall atmospheric haze.
    Subsequent photos - a cloud passes in front of the sun.

    I used the auto setting on the camera, so exposure is different for each photo.

    Question: what Poser infinite light settings would you change to mimic (fake if you prefer) this effect ?
    I'd guess both Shadow Blur Radius and Shadow Strength ?

  • You could try to mime the effect of the atmosphere haze and the clouds on the direct sunlight by a large surface, say a dome, with variable transparency and noise on the IOR.
    A second dome, not casting shadows, could be used to add the atmospheric diffusion light.

  • Poser Ambassadors

    @3dcheapskate - for effect of changing shadow blur radius see scrappy renders below. AFAIK shadow strength has no effect in Superfly. In your photos it's worth keeping in mind that not only is the exposure different for each image but the white balance will be different too. That has a big effect on the overall colour & mood.

    0_1525983528189_SBR 0.5.jpg

    0_1525983547538_SBR 1.jpg

    0_1525983558217_SBR 5.jpg

    0_1525983570211_SBR 20.jpg

  • Just to be clear, we're talking ray traced shadows, not depth mapped, right?

    For the record, I love me my fill light with the EZ Dome. Just a tad is all you need.

  • Poser Ambassadors

    AFAIK if the option for depth mapped shadows is switched on it just gets ignored in Superfly. I don't think that changing Shadow Min Bias makes any difference either ;)

  • @caisson Good to know. Was the OP using Superfly or Firefly?

  • Poser Ambassadors


  • @caisson

    Smith Micro should have images like that built into Poser for every setting and every node shader. For example if you highlight over a shader node in the material room, it shows a popup window with an example of how to use it in various ways. If you highlight over the shadow blur radius setting, it should show your image as a small popup window that you can expand.

  • @zazop Man, I would love something like that even if we had to build the pop-up help files ourselves.