Iray Ghost Light Kit

This product:

http://www.daz3d.com/iray-ghost-light-kit

I admit, I was a little disappointed to discover this isn't a shader to create ghost effects for Iray renders... :) However, can someone who's purchased it give an idea of what it actually is? I know there's a description, but I'm still a little confused at what the tool is meant to achieve. Is it purely a way to simply add additional light into a scene or something else? If so, I'm not understanding what advantage this has over just manually adding extra lights.

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Comments

  • ablazeablaze Posts: 56

    I don't have it,  but I have used this concept in my own renders in the past already.  It's basically a plane,  set to emitter,  which you would put infront of a window,  and set the cutout opacity down to an incremental number like .001 so the plane is effectively hidden but still emitting light.  Fairly easy to do.  Gives a balanced area light.

  • KindredArtsKindredArts Posts: 1,185

    Ablaze pretty much summed things up. Simple emissive mesh lights will show up in specular reflections, and of course, show up in the scene itself. Ghost lights don't show up in either, so you can use them as a invisible light source without affecting your scene. You can use photometrics instead, but they will produce a different type of light with their own drawbacks. Like most things, you can do this yourself with planes and a little shader work - i've just condensed it down into an out-of-the-box solution.

  • nDelphinDelphi Posts: 1,836
    edited December 2016

    They are easy to use and I like how uniformly the light is. No more fumbling with light types just to get more light in interior scenes for me, a definite plus. Sorely needed. Thank you, KindredArts.

    Post edited by nDelphi on
  • KindredArtsKindredArts Posts: 1,185
    nDelphi said:

    They are easy to use and I like how uniformly the light is. No more fumbling with light types just to get more light in interior scenes for me, a definite plus. Sorely needed. Thank you, KindredArts.

    Thanks nDelphi, very glad to hear it! Happy Rendering :)

  • HeraHera Posts: 1,879

    >and set the cutout opacity down to an incremental number like .001

    Will it still emmit any light when set so low?

  • KindredArtsKindredArts Posts: 1,185
    Hera said:

    >and set the cutout opacity down to an incremental number like .001

    Will it still emmit any light when set so low?

    Yes, mine are set to 0.0001 and still emit fine.

  • RAMWolffRAMWolff Posts: 9,703

    Saw, read and carted.  This looks very very useful.  ESP for interior scenes.  Thanks so much for making this! 

  • KindredArtsKindredArts Posts: 1,185
    RAMWolff said:

    Saw, read and carted.  This looks very very useful.  ESP for interior scenes.  Thanks so much for making this! 

    You're very welcome Wolf, Thanks very much for picking it up!

  • Serene NightSerene Night Posts: 17,166

    I'm curious if they render slowly? I have quite a few emissive sets and they are lovely but take lots of time to render and draw

  • KindredArtsKindredArts Posts: 1,185

    I'm curious if they render slowly? I have quite a few emissive sets and they are lovely but take lots of time to render and draw

    Well that's the million dollar question isnt it. Even though it's deployed as a general lighting solution, I made this set specifically to tackle lengthy render times in enclosed environments. Whether i succeeded or not is up to ultimately up to you guys, but I'm confident. I wouldn't even consider rendering an interior without using these, and i've been using my own rough setups for the last six months. An interior render that would have taken hours to clear before, only takes minutes for me now.

    I imagine the mesh lights you are using are standard, visible mesh lights? If so, it's not only diffuse emission that's being calculated, but also reflective/refractive caustics which are further bounced many times over. Ambient diffuse lighting is the best way (that i know of) to directly light surfaces and relinquish lengthy workload from render iterations. You can still have those visible mesh lights creating neat reflections on your scene, but think of ghost lights as big fill-lights to bathe your scene in light. 

    If you click the image above, it has a perfect example of a before and after, given the same render time (about 6 minutes on a single titan x). If you're not quite sold on the idea, then by all means wait until people drop in to give their perspective. I've been speaking to people in a few different threads about this, so hopefully some results will roll in shortly. :)

  • pdspds Posts: 586

    I'm curious if they render slowly? I have quite a few emissive sets and they are lovely but take lots of time to render and draw

    As probably single polygon meshes, these should render quite fast. The benefits of the product seem to be in adding more light to a scene to help renders "converge" faster with less noise, and easy to use (and perhaps more intuitive) presets for light output and temperature. Like many items in the store, while some people could recreate the product, many might not be able to, and for those who can, it's always a trade-off of time vs. money. With the sales price on this, I think a lot of people will be happy to buy it because they'd rather spend more time making art than building light presets. I hope it does well as KA puts out great products and supporting quality vendors is a good thing, IMO. :-)

  • KindredArtsKindredArts Posts: 1,185
    pds said:

    I'm curious if they render slowly? I have quite a few emissive sets and they are lovely but take lots of time to render and draw

    As probably single polygon meshes, these should render quite fast. The benefits of the product seem to be in adding more light to a scene to help renders "converge" faster with less noise, and easy to use (and perhaps more intuitive) presets for light output and temperature. Like many items in the store, while some people could recreate the product, many might not be able to, and for those who can, it's always a trade-off of time vs. money. With the sales price on this, I think a lot of people will be happy to buy it because they'd rather spend more time making art than building light presets. I hope it does well as KA puts out great products and supporting quality vendors is a good thing, IMO. :-)

    Well you put it far more elegantly than i did pds, thank you :)

  • pdspds Posts: 586
    pds said:

    I'm curious if they render slowly? I have quite a few emissive sets and they are lovely but take lots of time to render and draw

    As probably single polygon meshes, these should render quite fast. The benefits of the product seem to be in adding more light to a scene to help renders "converge" faster with less noise, and easy to use (and perhaps more intuitive) presets for light output and temperature. Like many items in the store, while some people could recreate the product, many might not be able to, and for those who can, it's always a trade-off of time vs. money. With the sales price on this, I think a lot of people will be happy to buy it because they'd rather spend more time making art than building light presets. I hope it does well as KA puts out great products and supporting quality vendors is a good thing, IMO. :-)

    Well you put it far more elegantly than i did pds, thank you :)

    Cheers, KA!

  • marblemarble Posts: 6,546

    I have the lights in my cart but waited a while before buying to see if anyone has used them. Probably 90% of my scenes are interior and I have had a long running battle trying to light them adequately in the restricted space available. I have tried using the dome and leaving off walls an roofs/ceilings but that's not ideal. I have made emissive planes too but this set seems to add convenience so I'll probably buy. I hope this thread gathers more opinions, however. I can't try them myself because my PC is being shipped to my new home and is still a few weeks away from delivery.

  • KindredArtsKindredArts Posts: 1,185
    marble said:

    I have the lights in my cart but waited a while before buying to see if anyone has used them. Probably 90% of my scenes are interior and I have had a long running battle trying to light them adequately in the restricted space available. I have tried using the dome and leaving off walls an roofs/ceilings but that's not ideal. I have made emissive planes too but this set seems to add convenience so I'll probably buy. I hope this thread gathers more opinions, however. I can't try them myself because my PC is being shipped to my new home and is still a few weeks away from delivery.

    Absolutely, i'd rather have cautious customers than inevitable refunds - By all means, wait until some feedback rolls in. The majority of the scenes i play around with are interior sets, and i've been tackling the same issues as yourself. I tried removing walls, removing the ceiling, setting the ceiling to emissive, hiding meshlights/photometrics out of shot, and much ... much more. I'm not trying to market this as a magic bullet to everyones rendering woes, but i think it's a solid method that's worth adding to your arsenal. I am biased however, so again, wait for some feedback if you're unsure.

  • These responses were very helpful. Thank you. :)

  • Simple emissive mesh lights will show up in specular reflections, and of course, show up in the scene itself. Ghost lights don't show up in either, so you can use them as a invisible light source without affecting your scene.

    You mention specular reflections, but what about regular reflections - such as in a mirror? Do the emitting surfaces show up in those? If there was a big mirror on the right hand wall of the kitchen scene above, would we see the kitchen ceiling and neons, or big squares of light?

     

  • KindredArtsKindredArts Posts: 1,185

    Simple emissive mesh lights will show up in specular reflections, and of course, show up in the scene itself. Ghost lights don't show up in either, so you can use them as a invisible light source without affecting your scene.

    You mention specular reflections, but what about regular reflections - such as in a mirror? Do the emitting surfaces show up in those? If there was a big mirror on the right hand wall of the kitchen scene above, would we see the kitchen ceiling and neons, or big squares of light?

     

    Sorry, when i say specular reflections, i mean anything other than diffuse light reflection. They will not show up in mirrors nor any glossy surface.

  • Well then, cart city it is. Thanks.

  • BTW, my "specular" question is a result of long term Bryce use. Bryce has a pseudo specular highlight system, so surfaces have separate diffuse, specular and reflective properties. As I move more into physically based rendering, I'll catch up on the proper terminology.

  • Simple emissive mesh lights will show up in specular reflections, and of course, show up in the scene itself. Ghost lights don't show up in either, so you can use them as a invisible light source without affecting your scene.

    You mention specular reflections, but what about regular reflections - such as in a mirror? Do the emitting surfaces show up in those? If there was a big mirror on the right hand wall of the kitchen scene above, would we see the kitchen ceiling and neons, or big squares of light?

     

    Sorry, when i say specular reflections, i mean anything other than diffuse light reflection. They will not show up in mirrors nor any glossy surface.

    Excellent...Can they also be used as directional lights?  I have some mesh lights from Elianeck that I love.b but they keep getting into the camera or reflecting in glass.

  • KindredArtsKindredArts Posts: 1,185

    Well then, cart city it is. Thanks.

     

    BTW, my "specular" question is a result of long term Bryce use. Bryce has a pseudo specular highlight system, so surfaces have separate diffuse, specular and reflective properties. As I move more into physically based rendering, I'll catch up on the proper terminology.

    Great stuff, thanks peter! If you have any problems, let me know.

    Don't worry, terminology is all over the place. I'm not even sure i'm using the right terminology most of the time, i tend to just parrot whatever i pick up from documentation. Are they even using the right lingo? Who knows!

  • One more query: In which situations would you decide between using the vertical and horizontal lighting options?

  • KindredArtsKindredArts Posts: 1,185
    edited December 2016

    Simple emissive mesh lights will show up in specular reflections, and of course, show up in the scene itself. Ghost lights don't show up in either, so you can use them as a invisible light source without affecting your scene.

    You mention specular reflections, but what about regular reflections - such as in a mirror? Do the emitting surfaces show up in those? If there was a big mirror on the right hand wall of the kitchen scene above, would we see the kitchen ceiling and neons, or big squares of light?

     

    Sorry, when i say specular reflections, i mean anything other than diffuse light reflection. They will not show up in mirrors nor any glossy surface.

    Excellent...Can they also be used as directional lights?  I have some mesh lights from Elianeck that I love.b but they keep getting into the camera or reflecting in glass.

    They won't work in quite the same way as the standard photometric directional light. They are however completely invisible in the scene. Here's a quick example:

    As you can see, the meshlight is almost intersecting with the characters skin, but at render-time it's completely invisible. This scene is lit by 100% diffuse ghost lights, no hdri nor supplementary lights.

     

    glkcomparison.jpg
    1920 x 2160 - 875K
    Post edited by Chohole on
  • KindredArtsKindredArts Posts: 1,185

    One more query: In which situations would you decide between using the vertical and horizontal lighting options?

    Hey xeno, that's really just for ease of use. I included horizontal lights on top of the free-standing ones so people could set-up downward directed lighting without rotating the normal lights. There is no difference between them other than the orientation. I use them to quickly set up fake ceiling lights.

  • Saw it, bought it and after only a few test render LOVE IT!

    As pds wrote > The benefits of the product seem to be in adding more light to a scene to help renders "converge" faster with less noise <

    I agree to that! In a test scene on an attic before i fought with a big neon tube lamp, cranking up the lumen more and more, but with poor results. After 10 minutes and 200 samples on an gtx 960 the scene still  looks like if i view through a night observation device. Unusable, or eventually usable after some 1,000 render samples after hours.

    Then i added 2 ghostlights to the roofs windows and voila: after the same time and render samples the result was nearly noise free.

    This tool not only saves time, it makes more attractive rendered images. I'll never give it back, even if someone forces me to do so :-)

     

    shh: don't hesitate to buy it, there are only very few available on stock, more have to be manufactured by approved ghosts on full moon...

     

  • KindredArtsKindredArts Posts: 1,185

    Saw it, bought it and after only a few test render LOVE IT!

    As pds wrote > The benefits of the product seem to be in adding more light to a scene to help renders "converge" faster with less noise <

    I agree to that! In a test scene on an attic before i fought with a big neon tube lamp, cranking up the lumen more and more, but with poor results. After 10 minutes and 200 samples on an gtx 960 the scene still  looks like if i view through a night observation device. Unusable, or eventually usable after some 1,000 render samples after hours.

    Then i added 2 ghostlights to the roofs windows and voila: after the same time and render samples the result was nearly noise free.

    This tool not only saves time, it makes more attractive rendered images. I'll never give it back, even if someone forces me to do so :-)

     

    shh: don't hesitate to buy it, there are only very few available on stock, more have to be manufactured by approved ghosts on full moon...

     

    I could kiss you! Thanks, i've been waiting for some feedback to roll in and that's great to hear. The more you work with them, the more they will work for you, so keep tinkering Wolf. :)

  • kyoto kidkyoto kid Posts: 37,896
    edited December 2016

    ...from the promos it looks very good.  Hoping to see more results (maybe a Ghost Lights Render Thread?).  On the wishlist for now as am broke until "next year". 

    Post edited by kyoto kid on
  • marblemarble Posts: 6,546
    marble said:

    I have the lights in my cart but waited a while before buying to see if anyone has used them. Probably 90% of my scenes are interior and I have had a long running battle trying to light them adequately in the restricted space available. I have tried using the dome and leaving off walls an roofs/ceilings but that's not ideal. I have made emissive planes too but this set seems to add convenience so I'll probably buy. I hope this thread gathers more opinions, however. I can't try them myself because my PC is being shipped to my new home and is still a few weeks away from delivery.

    Absolutely, i'd rather have cautious customers than inevitable refunds - By all means, wait until some feedback rolls in. The majority of the scenes i play around with are interior sets, and i've been tackling the same issues as yourself. I tried removing walls, removing the ceiling, setting the ceiling to emissive, hiding meshlights/photometrics out of shot, and much ... much more. I'm not trying to market this as a magic bullet to everyones rendering woes, but i think it's a solid method that's worth adding to your arsenal. I am biased however, so again, wait for some feedback if you're unsure.

    Oh, I went ahead and bought the set because I am sure you have struggled with the same interior lighting that I have. Unfortunately I can't test them yet because my PC is in a container on its way to my new home here in New Zealand. I'm told it is 2 or 3 weeks away still. Can't wait to get busy again though.

    I also recently bought Painter's Lights which I have had on my wish list for some time. Again I can't play with them yet but, in your opinion, would they make a good combination with your mesh lights? Maybe for a slightly lower ambient with a highlighted figure in the room?

  • KnittingmommyKnittingmommy Posts: 8,110
    edited December 2016

    I haven't had a chance to test these out yet.  Still waiting on a render to finish that I started yesterday so I can see how they work.  The idea looks great.  I've played around with mesh lights on my own, but I think I'm missing something.  I'm really looking forward to seeing how these work out of the box.  I have a few indoor scenes that took forever on my computer to render (CPU only) that I'd love to see how these impact on the rendering times.

     

    edit: fixed spelling

    Post edited by Knittingmommy on
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