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StCanas

Global Illumination

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i have nothing against asking its actually asking the same thing in a new topic, so many knowledge is being written and "lost" this way, i try to encurage that questions are posted in old topics thats all...

so as u say keep the forum alive i say keep the topics alive =)

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but if they find the topic they wouldnt need to ask the question :D

anyway lets move on :)

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    Lesia44, had a grumpy moment so sry if it was too forward, some topics just repeat alot =)

    Don't worry, it's not a problem. If it hadn't been so late I would probably have done a little searching first. Anyway, it could have been worse - you could have ticked me off for not looking in the instruction manual as well!

    Since starting this thread I've looked around this forum and others. General concensus seems to be that AR has a serious problem with flickering (an insermountable problem, even) yet for me, in this case at least, changing to Camera Animation seemed to do the trick.

    Cheers

    Karl

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    Hi Lesia44,

    I think there is some good advice here about using multiple lights in a scene.

    So far in my (fairly limited) experience it is best to set up a lighting scheme in Cinema with Area and point lights (usually one area light as the main light source and a few point 'fill' lights). Once this is giving fairly satisfactory results, then add Global Illumination to help fill the light in the scene out - being careful to keep the light intensity settings (apart from the main area light) fairly low. The GI is set to around 70-85% accuracy but the strength is set to around 80-100%. With camera animation used as the GI type this can help to smooth the artifacts because the GI solution is getting plenty of help from the lights to calculate its samples. Obviously these settings are not written in stone and will vary depending upon the particulars of any given situation.

    The trick is to almost paint a scene with lights - starting by using low settings (apart from the main light) - adding GI to help bounce the light around.

    Oh, and because of the multiple light setup you don't have to put the GI bounces to a high level. 2 bounces saves render time whilst being just enough to ping light samples around a bit.

    Also, for anyone interested there is an enormous thread on CGTalk about a VRay plugin becoming available fairly soon (apparently):

    http://forums.cgsociety.org/showthread.php...age=1&pp=15

    VRay really is one of the highest quality renderers available and because of the team involved (Renato Tarbella, Stefan Illaub etc) the integration with C4D promises to be very tight. I know quite a few people (myself included) are hoping that this one will prove to be the one-stop solution we've always wanted for Cinema with very fast GI rendering times and the highest quality currently available for Arch-Vis.

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    When I first started out with AR. The Camera Animation option seemed to work at first on my test scenes.

    A ball object for example, moving around the scene would render very nicely.

    But once I got into rendering moving charaters with it. The flickering was still there.

    As I have reported, in this particular instance Camera Animation seems (for the most part at least) to have solved the problem. Having said that, your quote above is probably right on the money as the nature of the attachment will show. You'll see that the scene that gave me the problem is essentially static in nature so the Camera Animation solution is probably of limited effectiveness.

    Cheers

    Karl

    EDIT: By the way, I should make clear that the attached file is the problem solved version (well, almost solved if you look close enough!). The original render looked like a disco at a cheap wedding!

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    I think there is some good advice here about using multiple lights in a scene.

    I'm glad I started this thread as this little pool of knowladge is going to send me off in some interesting directions.

    Interesting news about Vray and thanks for the link.

    Cheers

    Karl

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    Im doing an outdoor scene and I was using GI(Object anim, 60% accuracy, 150 samples, min 10, max 40) and one infinite light.

    In stills it looked perfect but when it came to do a test render I found there are alot of small flickering problems. Ive tried turning accuracy up but the flicker is still there. Ive tried standard GI, object and camera anim GI. Ive tried the settings on http://www.mvpny.com/RadTutMV/RadiosityTut4MV.html and they were interesting but ultimately didnt solve the problem. I cant bake the GI because there are far too many objects and some are uvmapped and others have tiling textures.

    So Im left now with either having slightly flickering GI animation or...light the entire scene with default lights. So Ive made a start at this, using my 1 big infinite light( kinda like a sun) and about 7 omni lights with linear falloff placed in the worst areas of shadow.

    What kind of lights should I use to emulate GI? where should I place area lights to get them to read well? I know it depends on the scene but perhaps someone has some wisdom on this.

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    Thanks scottA I will give that a try with my next scene I do with GI, I found that simply painting my scene with 1 infinite light for shadows and 17 coloured omni lights and area lights ended up giving me results which look almost as good as GI and it renders about 12 times faster with the standard lights than it did with object GI(6hour render now takes 30 minutes). This is a big bonus when I know Ive got lots of small flythroughs to do for the client and I can now do fast test renders and get it looking right smile.gif. Sure Im missing the little shadows on the edges of objects etc and I would like those but for the end product its not really necessary.

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