Lighting help required, please :)

Orion_UkOrion_Uk Posts: 0
edited September 2012 in Carrara Discussion

Hi all :)

I have finally started to look more in to lighting for my scenes and how better to illuminate them! ;)

I cant seem to get rid of the jagged lines that you see on the wall to the left of the screen and the other side of the light! I was hoping for a cleaner `line` / fall off but not sure if this is an error in the way Carrara calculates lighting or a user error :P

I have a basic cylinder (with anything glows) and a red glass material, also the color red in the glow channel, with aura enabled. I have two smaller cylinders either end with a metal shader on them. Ambient light set to 0%.

This is being done in Pro (64bit)..

Any advice to get rid of those jagged edges would be great please ?

Thank you :)

EDIT: Sorry, forgot to mention the `Bulbs` in the scene.. Settings for that attached also :)

My guess is that its some thing to do with how light travels through/round the geometry of the `caps` at each end of the tube light???

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  • GFHELGFHEL Posts: 24
    edited December 1969

    Hi Orion,

    Did you try to switch off "Show Photon Map"? This is only meant to be a quick preview of the indirect light calculation, and produces just such artefacts.

  • Orion_UkOrion_Uk Posts: 0
    edited September 2012

    GFHEL said:
    Hi Orion,

    Did you try to switch off "Show Photon Map"? This is only meant to be a quick preview of the indirect light calculation, and produces just such artefacts.

    Hi and thanks for the reply :)

    Yes, I am afraid that I have tried that with no change :(

    The forum wont seem to allow me to upload the .Car file so its prob gonna be a hit and miss / Q&A method of resolve :P

    Just trying another render with` Compatibility shadows mode` !!

    EDIT:` Compatibility shadows mode` ...made no difference :(

    Post edited by Orion_Uk on
  • GFHELGFHEL Posts: 24
    edited December 1969

    I'm still trying to reproduce this.

    Something indeed showed up when I scaled up the caps at the tube ends. Small, but also weird. It vanished when I increased the "Standoff" value of Anything Glows.

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  • Orion_UkOrion_Uk Posts: 0
    edited December 1969

    Hay, Thank you for going to so much trouble (taking the time to recreate the scene) and helping me out :)

    I will give that a go and see what happens, then post results :)

    V-kind of you indeed ;)

  • GFHELGFHEL Posts: 24
    edited December 1969

    That's part of the fun, trying to find something out :-)

    What are your Anything Glows settings, btw?

  • Orion_UkOrion_Uk Posts: 0
    edited September 2012

    Well, its definitely linked to FULL indirect lighting in some way!

    Changing it to `Ambient occlusion only` produces the result in the attached image.

    Does that shed any light on the problem ?

    I now have `cog` shadows/reflections (as in your image), sure they should be round! Gonna look at occlusion radius and improved edge settings or photon count!


    EDIT: Attention span fading, long day with the kids and brains giving up :(

    I will take another look tomorrow at some point, Many thanks for your time and help GFHEIL :)

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    Post edited by Orion_Uk on
  • 3DAGE3DAGE Posts: 3,251
    edited December 1969

    HI Orion :)

    This is partly due to the way Anything glows works,..
    creates light sources per facet / vertex/ bounding box.

    and partly due to the way you've built the Light model and fittings.
    Cylinder "primitives" have many more edges and Tri's than you really need for this, and the ends of the cylinder will also be effected by Anything glows, and since the End caps, are right next to the "Bulb" ends, you'll get issues with shadows.

    You could make a single cylinder with some divisions, and make the Middle section a separate shading domain (with glow) while the ends sections are just a simple metal shader.
    then only the shading domain with glow (the bulb section) should be effected by the Anything glows light.

    If you're using anything glows lights, you don't necessarily need to have Indirect light enabled in the renderer.
    AG should cast light,...
    Glowing objects require Indirect light enabled,.. to emit light. (See pic)

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  • GFHELGFHEL Posts: 24
    edited December 1969

    The cogs look like a small edition of the large edges... The nearest thing to your jagged shadows I get so far is when I turn on "Soft Shadows" with Fast quality.

    Played around with excluding the "metal" caps from the Anything Glows light, or switching them off throwing shadows. This didn't help, but I stumbled upon a mistake in my scene. There are three cylinders with the same name, "Cylinder". I had the Anything Glows set to just "Cylinder" without thinking that it now had are three to chose from. Obviously it took the one near the wall, and that resulted in the black spot. Naming all three differently, and setting the Anything Glows correcly to the tube instead of a cap, resulted in an unperturbed rendering, using your settings.

    I'm running out of clues.

    Maybe some sleep will bring fresh perspectives. I would like to see your scene without cogs :)

  • Orion_UkOrion_Uk Posts: 0
    edited September 2012

    Hi and thank you both for being so helpful :)

    I took your advice (3Dage) and re made the `Bulb` tube light as one single mesh with two shader domains :)
    As you can see, it worked a charm and I am pleased with the results :)
    I cant seem to get the light to go above 200 (Red Anything glows light) but will try to use a lighter red in for the glow color as it seems a little dull to me!

    Thank you both for your input, time and help. Its by no means near completed and I have a long way to go regarding texture mapping and adding more objects/detail so will try and post the final result as and when I can. You may be interested how this little project draws to a conclusion :P

    I just downloaded Tyler (free from SmithMicro for a limited time to poser 9-2012 owners, with serial, I also brought Poser physics at a discount rate!) but he is not acting as expected! While he renders great, there seems to be some weight mapping issues (OSLT) once exported from Poser to Carrara! The rib cage (under the arms) deforms the arms when trying to pose them hanging down the side of the body! Everything else works great but that! I was intending to do a scene where Tyler and Miki4.0 battle a Cyborg!

    Anyway, I am starting to babble now so I better head off :P

    Thank you both once again, hope the final render looks as good on screen as it does in my :)


    THANK YOU :)

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    Post edited by Orion_Uk on
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