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  • @starlingblue Bagginsbill has a shadow catcher on his web page as well. I have used it in the past, but it has been awhile. Not sure if it works with HDRI lighting or not. There are detailed instructions on the page for its use. https://sites.google.com/site/bagginsbill/free-stuff/shadow-catcher



  • @ribroast I think it works for FF only, could be wrong though...



  • @ghostship Yes, IIRC, shadow catching doesn't work in SF as yet, which is something I'd definitely like to see in an update in the not too distant future.





  • @raven
    Thanks for the hint, thats basically what I was looking for.

    You have to rotate the texture by PI/2 to match the mapping of the EnvSphere.

    But a problem is to get the HSV right, especially since the material is lit by the EnvSphere, that is, by itself.
    So the texture projection matches but the colors and brightness are totally off for me.
    Hmmm.



  • Also the projections on the plane and the sphere don't match 100%, the sphere appears to be slightly too small, but you can't make it larger since its already max. dimensions allowed.



  • here's an example

    0_1514836666115_projected environment test.jpg

    It's cool but the colors and the alignment don't match.
    You dont see it at first glance when you don't know where to look for the border
    but at a second glance it's very obvious and annyoing.

    I want to improve this if possible.
    Maybe its helpful if the plane would fade towards it's borders?
    Or maybe this would worsen things.

    Then maybe you could combine this with the shadow catcher mentioned previously.
    The surface projection from bagginsbill uses Cycle nodes but these also work with the Poser Surface in Superfly and vice versa for many nodes
    So maybe there is a way around to have the shadow catcher in SF in combination with the projected environment map? Bascially fade the map, like in the Shadow Catcher, with the shadow.



  • If you use my setup there is a possibility to change the strength (value) and colour of the map on the shadowplane.
    The problem is that the groundplan get lighted by the background lighting (or skydome) and it becomes lighther ( or darker) and the colour changes, especially with a blue sky.
    By changing the value and the colour you adapt the plane to the background.
    It's a bit of trial and error and you will need some testrenders to get the best result.

    Best regards,

    Bopper.



  • sorry, I am still confusing names on this board, I was using your setup with the HSV corrections and a ground plate disk and
    with the Environment Sphere from bagginsbill but with a different material,
    just the image into ambient color and everything else black/off.

    And with this sphere the projections dont match up with the ground plate since the sphere is slightly too small for the projection on the ground plate

    I think you are using a slightly different setup for lighting? A different dome and or material?
    Anyway it's pretty cool and probably the best we can have in SF.

    Yesterday I tried all possible things to combine this with a shadow catching material like bagginsbill had for Firefly, that fades to transparent where there is no shadow in SF, and it seems its just impossible.

    I plugged a DiffuseBsdf shader into a TransparentBsdf Shader and used AddClosure to mix both, and the strange thing is that this gave a material that was always transparent at the shadows and opaque everywhere else
    (when it should be just the opposite way) even when you inverted the output of the Diffuse shader.
    And this worked for an hour or so and dindt change no matter what I did and than it stopped working all together and I couldnt reproduce the effect.



  • @starlingblue if the plane is not matching up to the sphere maybe changing the camera's focal length will fix that.



  • Yes, maybe, have to try that a little bit
    But I prefer to be flexible with the focal length and often like to use 50mm.
    Also I am not sure if it will solve this, or just make the difference slightly smaller.
    It also has an effect where the camera is located, the more you move it off center the more difference I think.



  • Ok, now I followed more closely what @bopperthijs did with the background for lighting and now it works.

    Great. I am pretty happy.

    I would have preferred the dome since you can see it in the preview, but you can still use it in parallel and then switch it off



  • Now I used a circular groundplate, scaled, and

    Wave2D -> MathFunctions Gain -> MathFunctions 1-x -> Transparency to fade it towards the borders,
    works nicely, you dont see the borders even if colors or luminance are off.

    However I had to use the Surface Node, the Cycles TransparentBsdf gave me strange results again in combination with the DiffuseBsdf and AddClosure.

    Maybe I wasn't doing it right?

    Don't you use the AddClosure to add a transparancy to another shader?
    When I do that I get off color pixels where there had been no pixels at all when using the TransparentBsdf alone.

    And I found a disadvantage with using the Background for illumination:
    it's not reflected. So you need something else for reflections.
    0_1514922901619_fade test 3.jpg



  • For transparency you have to use a mixclosure node and not an addclosure. I show you how if poser is available again ( I'm in the middle of a massive render)



  • Thanks, I think I'll manage without a demo if you cant find the time, now that I know what I was doing wrong.



  • Hm, I think I do need an example - I dont get it to work either way.
    With Add Closure it seems buggy, with MixClosure I get a 50/50 mix which is semi transparent where the color for transparency is white.

    Also, I am not sure how you set up your background lit scene.
    Do you still use an IBL light? Or set the backgroud material to cast light?



  • @starlingblue
    Sorry for my late respond, but it got a little late last night
    Here are some screenshots how a simple mixclosure works:

    0_1515015922477_Mixclosure.JPG

    With a mixclosure you can mix between two different shaders : Diffuse, Glossy, transpant, emission translucent etc.
    With the fac input you can modulate between the two shaders. I have made a simple one with two diffuse shaders, one red, one blue. For the modulator I used a simple tile-function, but this can be anything: formula;s , 3d-functions, transparencymaps. (besides the new cycle-nodes, you can also use the old poser-functions.

    Here is the result:
    0_1515016315593_DemoBall1.jpg
    Perhaps you ask what this has to do transparancy? Replace just one of the diffuse shaders with a transparency shader
    0_1515016638826_Mixclosure2.JPG
    and this is the result:
    0_1515016670535_DemoBall2.jpg
    You can also replace the tile function with an transparencymap.



  • @starlingblue

    Here is the setting for a mirrorbal. Very simple.
    0_1515017113746_Glossy.JPG

    Just add a Glossy , be sure the color is almost white. With roughness you control the blurryness of the reflection.

    0_1515017237099_DemoBall3.jpg

    If you more questions, just ask. If I have time I answer.



  • Thanks for your time, this was really helpful.



  • @bagginsbill Besides the Primitive prop image. How did you set the actual background to have that sky?