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Need help with lighting

Using maya using HDRI, directional light, global illumination, ect.. and have several render passes of diffuse, ambient occlusion, ambient color, reflection, z depth, specular, object normals (for selecting), and shadow. When i get it all together in photo shop minus the zdepth blur It ends up like this and my boss claims it doesn't look real enough. If I could get some help as far as what is wrong that would be helpful. for an extra little notes my boss like applish style, "celebrating life", and no imperfections in the scene. But he claims that it doesn't look "real" enough. Any suggestions please.

1room.jpg

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  • frubes
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    ok well this could be a multitude of things. Firstly do you have a control image straight out of maya's renderer. Essentially, by rendering out all of these passes and putting them back together you should, in theory if you do it correctly end up with the same image that the renderer produces straight out of the box, so you need to have something to compare your final composite against.

    Second question, by rendering out passes what do you want to do with them?

    Thirdly, in what order are you putting the passes back together?

    Comments about the image:

    You will most likely need CC (colour correction) masks to composite the image correctly. If you make objects which you want to colour correct either Full red, green or blue with 100% self illumination (this effectively makes them a matte object). Make everything else in the scene black and you will get a pass which means you can select them in photoshop by just selecting the R G or B channel. Make sure you save out the alpha as it comes in handy to pre multiply stuff.

    You would get more red/brown bounce light in the alcove behind the coffin and this would be slightly darker than what you have at the moment.

    Your key light appears to have very little in the way of colour, you would get lots of blue coming in from the windows and sky and an orange/yellow from the sun (key light). At the moment the only colour in your scene is coming from the bounce light emitting off the coffin. I dont know how this fits in with your brief though.

    Use your zdepth mask to give a gradual dof from the camera to the coffin. The foreground would be quite a bit more blurred.

    Those windows are the worst bit, it looks like an aquarium out there. Im guessing its meant to be sky so i would suggest making a sky box in maya. Also if you cant get the vegetation looking right i would steer clear of it for the moment as its often terribly done in cg.

    Also, your texture for the floor needs to be much higher res as your loosing details. This may also have to do with some filtering in maya if its the same as max which blurs the texture. Plus it doesnt look like it has a bump or a spec. I would consider modelling the planks as you are so close to them.

    Theres more stuff but its things i would correct in comp (i use fusion) and too difficult to explain over the webs.

    Hopefully that helps a little!
  • JacqueChoi
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    JacqueChoi polycounter
    Upon first glance, I would also add your AO is way too strong, making it look almost cartoony.

    And it almost seems like an HDR image (which tends to lend itself to looking fake). Try using tricks and compositing methods to emulate limiting your dynamic range.

    First thing that gives it away from me, are the light shards from the left. The entire room seems like it should be more dramatically lit from the left if those shards were to penetrate the image. It would also bloom quite a bit leaving that side of the image much more washed out.


    I think overall you need to maniupulate this image in a way where it looks like it was a picture taken through a camera.
  • o2car
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    o2car polycounter lvl 16
    are those paintings or windows on the wall?
    I think in general you need more direction of the lighting. It looks very ambient to me.
  • fattkid
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    fattkid polycounter lvl 15
    I'm no lighting expert, but I'm pretty sure properly dialed in materials and textures make up a good portion of a nice render. Looks like you just have some basic flat colors and/or some basic procedurals/bitmaps. That in itself is making it look cartoony.

    Next I'd say the actual lighting itself needs work. It kind of doesn't really make sense. Where is all that light coming from? Seems way to substantial to be a window. Seems more like the entire side wall of the room?/church? is open to daylight.

    Are those windows on each side? I'm guessing so. The environment outisde the windows(?) doesn't seem very realistic either.

    As for rendering techniques, seems you're just throwing every technique in the book at it hoping it somehow just comes out like you want. It doesn't take all that for a realistic render if you know what you're doing, materials being a huge part of that.

    Seems like you got quite a few issues you might want to consider if you're going for more realism. If you have the time, maybe grab some Digital Tutors videos on Maya and Mental Ray, as well as Jeremy Birn's book, "Digital Lighting and Rendering". Good luck.
  • Mark Dygert
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    I don't think its the lighting that's letting the scene down, right now. I think you need to work on your modeling and materials. I've never seen square molding and you have a lot of it. Molding is pretty easy to make. Even if you're making a low poly scene, you can make high poly molding and bake it down.

    It all looks like it was made of the same material and painted with the same flat paint. The walls, chairs, molding, even the coffin stand (which is normally covered up by a curtain or flowers) all have the same flat look. The stand under the coffin looks really blocky and lacks the same level of definition as other objects in the scene.

    looking at this I would say the:
    Modeling is at 60%
    Textures are at 35% (you can have two white objects and they can have different material properties. Also they don't need to be the same shade of white.)
    Lighting at 80%

    The only lighting errors I see are the mysterious unearthly light coming from off camera where it looks like no real light source would naturally be. Maybe that is planned, I dunno... The outside lighting doesn't seem to be affecting the inside of the scene.
  • System
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    Not sure why you are rendering several passes for this? You could easily render one pass with all the information required and as a result would look alot more realistic. < mutiplying ao is killing the realism.

    The floor material is too blurry for an upclose shot like that plus it would look better as stone. Anyway there are so many things to say so better than words...
    1room_paintover.jpg

    .. a paintover!

    Edit - You need candles~ if someone didn't order any candles for my funeral I would wake up and beat them with my decaying limbs.
  • frubes
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    GCMP, if you are trying to achieve realism in a render you pretty much never take a straight up render out of max due to the fact its far easier to iron out inconsistencies and tweaks in compositing/post than it is to constantly re-render. You will loose an awful lot of time. Plus the passes you generate for compositing can be used for other things, such as falloff masks and colour correction masks etc.

    As i said in my initial post, if you comp it back together properly you should end up with the identical image straight out of max's renderer.

    Also, with regards to AO, there is no other way to comp an AO pass into an image other than to multiply it so from that perspective its right (edit, thats not strictly true. When you get into more complex compositing you use it for lots of differnent things but for the purpose of this its probably right). That being said where you put it in you comp (ie below the lighting pass or above the shadow etc) is important. About ao, it is a cheap GI fake and when dealing with realistic renders should be used sparingly and shouldn't really replce a well rendered GI solution.

    "Textures are at 35% (you can have two white objects and they can have different material properties. Also they don't need to be the same shade of white.)" - this is also a really important point, you shouldn't really let the value of your white materials go above `175 as when you come to push them later in comp they will blow out.
  • System
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    frubes - Nope, disagree. Lowering samples till the lighting is right is quicker and more intutive than rendering out seperate passes to manipulate in Photoshop. The thing is to get it looking right in the first place and with the out of the box render the result is more natural.

    You mentioned multiplying ao as the law, you can soft light, linear light, overlay and use many more blending modes with ao, there really is no limit.

    btw if I had to comp an image from mental ray I would render it without colour and add the colours later.
  • Slum
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    Slum polycounter lvl 18
    GCMP wrote: »
    btw if I had to comp an image from mental ray I would render it without colour and add the colours later.

    seriously? That's just crazy ridiculous. There's so much more to the way color bounces around a scene (indirect illumination, radiosity), that would be the worst idea ever.
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