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berilac
10-16-2005, 04:02 PM
Hi guys,

I am having a load of trouble setting up lighting in a gallery still shot.

It is for a friend, and he asked for a white walled gallery room with white plinths running down either side, each spot lit from above. The floor will be an off-white colour.

I have set up the basic scene just to get a feel for the lighting, as that is the most important factor in a scene like this.

Unfortunately, the room has no windows, so all the lighting threads and tutorials I have read kind of fall short. Unless of course I missed the point of them.

The thing is, I have set up twelve spots, but turned them off as initially I would like to set up the ambient light, so wish to do this a simply as possible to get a pure white feeling for the room.

Here is a wire shot of the scene; I have tried different set ups but have gotten nowhere. All there is is one huge area light, as I have no experience in scene lighting apart from what I've read and logically (well at least for me) this was my first choice.

Any advice would be most greatfully appreciated!

Thanks everyone.

Michael

Zarathustra
10-16-2005, 04:20 PM
I'm rendering right now or else I might take a stab at a mock up.

There was a thread recently this week with a similiar environment, closed room, no windows. It had a scaffold. Check that thread.

Do you want GI or no? GI is nice but I usually do a lot with area lights. More work but faster render (and preview in FP). You have to manually place lights to account for the bounce light you get with GI. That means at least having lights shine out from the walls, floor and ceiling with falloff and colored.

Search for threads by Otacon.

Sorry, that wasn't much but maybe gets you started

berilac
10-16-2005, 05:50 PM
That certainly does get me started. Thank you, and I shall search the forums now.
Hopefully soon, I'll be able to post (probably problematic) renders, which will enable specifics to be worked out.

Michael

otacon
10-16-2005, 06:39 PM
Depending on how realistic it needs to be, you could try using the ambient occlusion plugin. Heres a quick test i did using spotlights with shadow mapped shadows above the plinths, and using luminosity on the surfaces with ambient occluion. Took about 2 min to render.

berilac
10-16-2005, 06:50 PM
That's pretty much exactly what I'm looking for.
Thank you very much. This is the kind of stuff I really need to practise! I love good lighting.

I got ambient occlusion from Flay...not sure exactly how best to use it. Have applied it to the walls, plinths and floor...but am not sure how to manipulate the luminosity. How high did you set yours for the above image? Also, is ambient occlusion only applied to the diffuse?

Thanks again,

Michael

otacon
10-16-2005, 07:25 PM
Under the options for the ambient occlusion plugin, check the on box next to luminosity. It can affect anything you want it to, diffuse, color, luminosity, spec, gloss, reflection, etc..I had my walls set to 85% luminosity, and had these settings for the ambient occlusion:

number of rays- 20
shift-.65
max ray length-20' (this depends on if your model is to scale)

berilac
10-16-2005, 07:45 PM
Cheers otacon. My model is to scale; the room is 12' high, 30' wide and 60' long. Currently rendering a test...

I have read a bit about this plugin, but what exactly does the max ray length entail (with reference to object scale)?

The test image is better than anything I tried thus far, but very dead. What am I missing; I don't fully understand the ambient occlusion yet...I will read around other threads so don't feel obliged to respond though I wouldn't say no... :)

Thanks again.

berilac
10-19-2005, 06:20 PM
update

a bit better. certainly still needs improvement.
any idea what is causing the "seam" down the middle?

cheers

Michael

monovich
10-19-2005, 06:48 PM
I think Otacon's technique is probably fastest.

For reference, I had to light a gallery shot last year, and I used spotlights, area lights, and radiosity. I rendered with FPrime.

here's a capture of the light setup I used. Our gallery was a bit more dim and moody than yours, but maybe the general idea will shed some...um... light on your project.

uncon
10-19-2005, 07:23 PM
Since the cieling is lit up so well maybe the scene would do well with some actual light fixtures. The other thing I might suggest is to try adding a falloff to your spotlights, so the floor isn't lit up so much by the spots. Light falloff is something a lot of people forget about when they are lighting a scene.

berilac
10-20-2005, 10:43 AM
thanks guys

uncon: did actually one last render last night but didn't get to post. and it does include fixtures (yes they are currently rather dodgy).
no falloff, but i will try one now with a couple of changes. i think it needs to be less intense with a little more contrast. any ideas on good ways to achieve this. currently my luminosity is set rather high so i will try lowering that but that won't help with contrast i don't think...?

oh, and any idea about that 'seam'???

Michael

berilac
10-27-2005, 02:41 PM
ok...this time i have used an area light for each wall surface and left on ambient occlusion. the spot lights have faded so are unnoticable atm, and the area lights have no falloff.
looking a bit better i think

i'm trying for a more realistic room. white washed walls & eventually marble or white stone...

what do you think? i know it still needs a lot of work but i'm not sure where to go next...

thanks

- Michael

Zarathustra
10-27-2005, 02:55 PM
Experiment with falloff. I'm guessing that's why the stands at the back of the room are getting blown out.

Check to make sure the stands are flat on the floor. Their shadows, especially the ones in the foreground, look like they aren't.

IC12
10-28-2005, 01:09 PM
Getting there. Do you need the Area Lights? Ambient Light works really well with the amb occ plug in. I think your amb occ effect might be a bit too much. Try turning the Shift up a little.

Also, using a lower down duplicate set of your spotlights with a narrower cone angle gives a more realistic downlighter effect.

berilac
10-28-2005, 02:14 PM
IC12 : cheers for the comments.
i've tried turning of the area lights, upping ambient intensity...and changing the occlusion shift from .6 to .8 for each material (does that sound wise...?)

haven't tried duplicate set of spots yet but for testing i am now rendering the scene out with pale blue spots in a white room.
we shall see what it looks like in a couple of mins...

its rendering now and i can see i've probably put the ambient light up way too much (40%) and the scene looks dead and flat (gone from bad to worse. i deffinately need a LOT of lighting practise :))...will clever amb occ setting better this or a combination of that and better ambient light settings?...also the blue from the spots doesn't even show up; i assume they got washed out by the ambient light; if it works that way!

Thanks again.

- Michael

berilac
10-28-2005, 02:25 PM
this is another test i did prior to the one above. first tests with the area light falloff.
bit crappy...

i have badly named and saved the files so far. so i may set up a fresh scene soon...any ideas for an initial set up as i have ended up combining amb occ, area lights, ambient light and am getting pretty confused...:(

Carm3D
10-28-2005, 03:07 PM
If you have a compositor such as DFX+ or a paint program you can render each lighting element to a seperate image then combine them "in post."

http://www.carm3d.net/Images/Compositing.JPG

It would give you real-time feedback when you tweak the strength of each element. Notice I was even able to colourize each light source; all in real-time.

berilac
10-29-2005, 05:38 PM
that's a very cool idea! :) cheers carm

and i will give it a go, but i would like to try and get it close with lw first.

working on something different atm but will try more tests over the next couple of days...

- Michael

habaņero
10-30-2005, 02:39 PM
If you go with doing some of this is post, ctrl f8 -> add image filter -> PSD export is a killer.

As an example, you can give each surface a key shade that you can pick accurately with the famous wand tool set to accuracy 0, and save to different selections.

In photoshop CS2 you can do some/much of this editing on an original saved to hdr, and so it is incredibly powerful.

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