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OcatilloPicture
06-10-2007, 08:57 PM
Hi,

I have an architectural scene where the camera is inside a building and there is a mix of "Natural" sunlight streaming in the windows and artificial light inside the building. I have the relative brightness of the lights correct but I need to "Open the scene up a few stops" to make the sunlight hot and to bring up the shadows.

Is there a simple, global way to increase the exposure of a scene? My key light, the sun, is at 100%.

Any suggestions are welcome. Thanks.

Terry

voriax
06-10-2007, 09:44 PM
Set the key light higher than 100%? If it causes too much radiosity, turn the radiosity % down at the same time.
Otherwise you might be able to export to a HDR format and adjust the levels in Photoshop... from what I hear, everyone should use this for still shots..

Silkrooster
06-10-2007, 10:54 PM
Adding an additional light is suppose to increase the light in your scene by 1 stop. Therefore theoretically setting your light to 200% should do the same.
Silk

OcatilloPicture
06-11-2007, 10:52 AM
Thanks for the suggestions. I will try uping the light output beyond 100% (I didn't know that I could do that). I am not using radiosity because of the time hit in rendering.

I am dating myself, but I could swear that back in the days of LW 4 there was actually an "exposure" control or an F stop control that allowed you to control light intensity globally.

voriax
06-11-2007, 06:17 PM
Well, there is a global light intensity control, in the global illumination panel. I guess a lot of people have stopped using the GI standalone panel because they only ever used it to alter radiosity settings, which were more accessible through the render globals panel.
But yeah, the global light intensity is automatically at 100% anyway, so if you only have the one light you may as well set it to 200% :)
I'm not sure about any exposure controls within Lightwave..
You may get some info about it when you change camera settings, and depth of field has an F-stop setting - but it won't alter overall brightness.
I believe there are image filters that will do post-processing of a scene to alter exposure (Virtual Darkroom perhaps?).

I wonder if a realistic camera will be implemented to do this sort of thing? Would be interesting, but a hassle for anyone who doesn't like photography. I guess the closest we have is the Real Lens camera, but that doesn't have exposure control either.

Red_Oddity
06-12-2007, 01:11 PM
Global light intensity does just that, it adjusts the global light intensity, it doesn't take radiosity or luminous polygons into account.
In order to do an exposure adjustment on your entire scene (so this also involves changing the amount of light a luminous polygon emits when using radiosity) it's often easier to do that in post or with an image filter like the one attached.

danielkaiser
06-17-2007, 07:00 PM
I am dating myself, but I could swear that back in the days of LW 4 there was actually an "exposure" control or an F stop control that allowed you to control light intensity globally.

There was and is, it's under Camera Properties>Stereo and DOF, I don't think that will do what you want, render in an a FP format and adjust the exposure with Photoshop for stills or an composting package for image sequences, Image Viewer also has exposure controls, set the viewer to> Image ViewerFP , once rendered slect File>Image Controls.

As far as dating yourself, if your like me I'm the only one that will go out with me, in fact the other night I was so good, I treated myself to dinner and a movie.

DMarkwick
06-18-2007, 11:50 AM
As far as dating yourself, if your like me I'm the only one that will go out with me, in fact the other night I was so good, I treated myself to dinner and a movie.

LOL, did you get lucky? ;) :D

Extent
06-18-2007, 07:03 PM
If you don't want to do it in post you can load up the HDR Expose in your image filters. It dosen't deal in stops, but it's the same function as the exposure settings in your image viewer.

Rendering to a HDR format and doing it in post is the best way though.

Red_Oddity
06-19-2007, 03:24 AM
The script i attached in the previous post works with stops, it's a lot less confusing than working with black and white points.

OcatilloPicture
06-19-2007, 09:33 AM
Hi,

Thanks everone for your suggestions. I haven't had a chance to try them out but I will be soon and will post the results. I have a couple of scenes to crank out before this problematic one, so it's taking a bit of time to impliment tests.... but it is great that there is a comunity like this one where so many people are willing to share their experience.

Thank you all.

Terry