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skyPhyr
03-15-2002, 11:38 AM
Hi guys,
I'm just after some suggestions of what to do to improve this image. As you can see the side closest to the camera is very bright. I like using falloff cameras to assist in achieveing realistic lighting. Should I shift the light further away and increase it's intensity so that it will be more even at this point? or if I do that too much am I just killing the point of using a falloff light. This render doesn't matter so much - it will start to matter how it looks when I put complete rooms together - not just objects..

Also as far as the photon intesity 10,000 is the default, but I found that was way too much... 1,000 was plenty - does it vary greatly from scene to scene as that's a long way off the default...

BTW - for any of you that may have read my previous messages of errors with mental ray for maya - I suffered the same error making this in XSI - it appears to have been a result of my photons setup. I may not have had the final gathering radius sufficient or number of photons sufficient so when it got to some sections it never finished them because it couldn't find enough photons within the final gather radius.. (or something like that - anyway it was related to that)

Thanks for any hints and tips.

cheers,

skyPhyr

Atyss
03-15-2002, 09:19 PM
Bonjour skyPhyr,

Here are my recommendations:

1- The keylight is too strong. You can see on the corner of the bed that the surface is blasted. Also, I'm not sure of the mood you want to achieve, but this yellow tint is, imho, too yellow.

2- The falloff is too apparent. I would make it much larger. Increase the hotspot area, because the head of the bed is slightly darkened by the falloff. Also, putting 1 as the exponent will help, and make sure the light is linear falloff.

3- Decrease the umbra intensity of the light to 0. I always use 0 values for my lights.

4- The volumes are not enough defined. You will do this by adding backlights. Those lights should be white or blueish, and if you want you can disable diffuse. The goal is to create highlights that will make your objects appear more volumic.

5- Finally, put some fill light. The image is a bit grey. You need to lighten it a bit. A good idea is take a low intensity light but with a very saturated color. In the image I just putted one fill light, but you can add many more. Those light should have only diffuse enabled, and emit soft shadows. They should not provide more than 50% of the overall light.


http://membres.lycos.fr/grimoireinterdit/img_demo/LightingTheBed.jpg


Hope this helps
Salutations - Cheers
Bernard Lebel

skyPhyr
03-16-2002, 05:46 AM
Hi,

Thanks alot for all the suggestions. I've applied all of them. I also went and made a shader for the floor, as it was just the default scene material before. This was in an attempt to get rid of the bright lighting around the sides of the bed. I replaced it with a material that had no reflectivity and very little irradiance.

Though I still have the same bright sides. Anyone have any ideas?? Here's the scene now that all of the changes have been put in.

Thanks again for all the great advice.

Cheers,

skyPhyr.

Atyss
03-16-2002, 07:45 AM
Much better, don't you think? :)

Now I feel the roundness of the sheet.

But it could be even better. Your key light still blasts. Maybe there is too much specular. What you can try is duplicate your key light, split their intensity by 2, and on one of them disable specular. This will reduce the specular impact without reducing the light's intensity.

I think there are 2 things missing:

1- A shadow at the base of your object. This results in that the bed seems to float above the ground.
Observe any object that sits on the ground (wall, table leg, desk). You'll notice that, especially in soft lighting, the base is slighty (and very softly) shadowed.

2- A background. Right now the light comes from anywhere. The spectator needs some reference. Now your object seems to be in the middle of nowhere. If you just light a bit the floor behind (like with small spots) it would give a better understanding of the lighting. Adding some details (props) would help.

Finally, I think you should revise the camera. The bed is taking all the space. It touches every border of the image. Put your camera away, so we can see the surrounding, even if there's nothing to show. Then, place the camera in an way that the bed is more on the left OR the right side. The camera's view is as much communicative as what you see.


Hope this helps
Salutations - Cheers
Bernard Lebel


PS: A technique I like is to do my lighting in 2 steps. First you light your scene with Global Illumination (or whatever GI process), with rough settings, and you save a rendered image. Then you start building the lighting with spots, and you try to mimick the GI render.

macoy
03-17-2002, 12:15 AM
Do the GI first then...........
Thats a GREAT tip!!! , :)

skyPhyr
03-17-2002, 11:29 AM
hey - thanks again for all the tips.

I've taken the bed and put it in another scene which already had the base layout of an apartment.

I set the lighting up again and this time added a point light in the room to create the subtle downward shadows.

Thanks again for all the advice.

cheers,

skyPhyr.

skyPhyr
03-18-2002, 01:00 PM
Hi guys,

Any suggestions on what would improve the aliasing here??

I've got it set at 1,1 - how do I improve it without it getting blurry?

cheers,

skyPhyr.

Atyss
03-18-2002, 08:38 PM
Ok the lighting is becoming very good.

But some things could be improved.

Am I right if I say that the illuminated zone on the bed comes from a window? This illumination should more strong. Day light is quite powerful, and generally creates more sharps shadows.

Next, the lamp next to the bed should provide light. It can be a very soft yellow. The problem is that your light, right now, comes from a place that is not visible in the picture, and then the only light source visible does not emit light.

When I said that the spectator should have some visual reference, it also apply to light. Right now the reference (the lamp) does not provide light, so I am unconsciously wondering where the hell the light comes from. Since the window effect is not enough strong, I'm a bit confused and have a hard time understanding the image.

The point is that when you have a light reference in the scene, you can build anything on that. The spectator will always assume the light comes from this source, even if the source does not provide more than 30% of the overall lighting. As long as the spectator can read the image in a logical manner, it does not matter how exactly the lighting is built.

My best advice is look at interior design magazines. This is where I find ideas to light scenes (and in architecture zines and books, too). In these magazines you have great pictures, taken by professional photographs, so lighted by professional.


Hope this helps
Salutations - Cheers
Bernard Lebel

macoy
03-19-2002, 02:53 AM
try to set anti-alias to 0,2, and lower the threadhold from 0.2 to 0.1 or even 0.02, and you would get a much better result.

The pillows look a bit flat to me, but i dont know how to improve it, looking forward to tips from Atyss. :D

Atyss
03-19-2002, 04:31 AM
If the lamp can be turned in a light source this flat effect will be negated. The light coming from the light will create contrast (thus providing volume).


Salutations - Cheers
Bernard Lebel

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