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squeegie
10-01-2018, 03:18 PM
I am working on an office space with acoustic ceiling that has with suspended lights.
Should I use one big Area light to encompass all the lights, or should I create a light for each?
If I need to create one for each, should I still use area lights? I need to mimic an LED light bar with a soft lens, and these will be the primary source of lighting in the room.

Any guidance would be greatly appreciated.142965

Nicolas Jordan
10-01-2018, 10:24 PM
I would definitely use a separate light for each. You could use area lights or maybe try using primitive light to reference geometry for the shape of the light if you want to get more accurate.

Tobian
10-02-2018, 02:31 AM
What i would do is build a reasonable approximation of the light, as a model. render it as a square, with physical intensity of your luminous bits, saved as half float exr... then use that as a exr as a texture for area lights, which hover just underneath it, and increase your MIS samples for those lights to the approximate resolution of the image file. that way you are lighting the scene with something which looks like the light, but benefiting from multiple importance sampling, from nice big wide area lights.

JohnMarchant
10-02-2018, 03:21 AM
I would always use separate lights. No two lights are the same when it comes to the lighting, even the same bulbs with the same power can be different, try using IES as well if you can. It takes longer but you have more control to lighten up or darken areas of interest. It will make for a better scene as well. One light just wont give you that control. Just do one light, get the illumination how you want then clone it. Be aware that you dont need your initial light so bright as once you have cloned it, it will multiply the brightness.

RPSchmidt
10-02-2018, 06:55 AM
Consider all of your light sources when setting up your lighting as well. If you have external light sources, i.e., windows with "sunlight" coming in, that is going to add to your overall lux if you are using environment or portal lighting for your windows.

I set up an interior scene with a similar lighting scenario; inset track lighting in a huge office floor. I also had an environment light sampling a textured environment city image. It took me quite a while to find a balance between the interior and exterior lighting while also maintaining falloff for the interior lights that still allowed them to affect the overall lighting in the scene without everything getting blown out.

It turned out good, but I think I still have work to do to get those types of scenes nailed down.

I think someone asked Tim Parsons if he could do some tutorials on his lighting and setup in his interiors... perhaps he would be able to share some pointers with you (and us) on that.

squeegie
10-02-2018, 10:53 AM
Ok.. so I went with the IES lights, and they look pretty damn good. The manufacturer was kind enough to include them on their website, so that was a big plus. I am hitting another snag though.
I am getting a lot of color bleed from the floor onto the ceiling tiles... so much that it is turning them a weird orange-ish color (I'm assuming it is the secondary bounce coming from wood laminate flooring being cast onto the white acoustic ceiling tiles).
In the past, I would add a large area light shooting upward from the floor to wipe out the bleed. Is there a better way? It seems like with 18 IES lights, there should be more than enough bounce to keep the colors from being wonky... but maybe I am looking at this the wrong way?

I apologize in advance for all the questions, but 2018 has me second-guessing what little bit I already knew.. and if there is a better way I am all ears.

Nicolas Jordan
10-02-2018, 11:34 AM
Ok.. so I went with the IES lights, and they look pretty damn good. The manufacturer was kind enough to include them on their website, so that was a big plus. I am hitting another snag though.
I am getting a lot of color bleed from the floor onto the ceiling tiles... so much that it is turning them a weird orange-ish color (I'm assuming it is the secondary bounce coming from wood laminate flooring being cast onto the white acoustic ceiling tiles).
In the past, I would add a large area light shooting upward from the floor to wipe out the bleed. Is there a better way? It seems like with 18 IES lights, there should be more than enough bounce to keep the colors from being wonky... but maybe I am looking at this the wrong way?

I apologize in advance for all the questions, but 2018 has me second-guessing what little bit I already knew.. and if there is a better way I am all ears.

In my opinion the color bouncing from the floor to the ceiling is realistic and accurate to how it should look in reality. I guess you could trying doing a single GI bounce and use a floor light as a fake light bounce to wipe out the color on the ceiling like you have suggested if your really trying to control the look.

squeegie
10-02-2018, 03:10 PM
I just don't understand what I am doing wrong here. I have the exact same surface settings on the sides of the acoustic tiles as I do on the sides of the lights (painted white metal)... yet they are totally different. Not to mention that the tile color is supposed to be white as well. The ceiling is suspended, and there is a matte black area above it (per the builder), so I lose any additional bounces from that area.

The area light on the floor solves the problem with the color, but just as Nicolas stated, it ruins the realism ( it has been turned off in this example).

I'm beginning to feel like I have bitten off more than I can chew on this thing... 142968

Tim Parsons
10-02-2018, 09:23 PM
I almost always add a bounce light pointing up and other fill lights in my interiors. Keep in mind that "real" lighting doesn't look good, if it did there would be no need for light designers and gaffers. Also keep in mind that while you may have the exact same surface settings on the two pieces of geometry there maybe something wrong with the geo itself. 2018 is more fussy than previous versions when it comes to accidently doubled up polys etc., so double check that.

Ma3rk
10-03-2018, 03:44 AM
I just don't understand what I am doing wrong here. I have the exact same surface settings on the sides of the acoustic tiles as I do on the sides of the lights (painted white metal)... yet they are totally different. Not to mention that the tile color is supposed to be white as well. The ceiling is suspended, and there is a matte black area above it (per the builder), so I lose any additional bounces from that area.

The area light on the floor solves the problem with the color, but just as Nicolas stated, it ruins the realism ( it has been turned off in this example).

I'm beginning to feel like I have bitten off more than I can chew on this thing... 142968

Just take smaller bites and chew slowly. ;)

I am curious though why you went with a series of that particular ies light rather than just put in one, simple linear in your "fixture" area?


And kinda expanding on what Tim is alluding to, sometimes being literal isn't necessarily what looks best. You have way, WAY, more options & control digitally than in the real world. And I'm somewhat speaking from experience here as that's what I actually do for a living. Anyway, I got into all of this with Lightwave 4ish to try and do essentially set previz, and it's taken until now that I feel I can actually take a model & light it as I would in the real world. But in all fairness, best practices is what works for you. I might try 3, 4, or more variations until I'm satisfied to show someone.

I've posted earlier versions of these on some other threads, and they're still very much works in progress, but the workflow is pretty straight forward; find a camera angle & light for it. And not every angle is best suited for just one, all encompassing lighting scheme but you can often make it work for several. And not every set is photogenic from every angle anyway.

Thes are using a model I purchased, largely to see what I could do with it. Nothjing couldn't have been done entirely with Lightwave (I've had to adjust a few things as it was). All of the textures import as Standard so each need to be tweeked, (still finding some errants), and there was no lighting what so ever. I simply imported into Lightwve as an FBX & just started in.

I'm finding that having "bad" texture settings (gloss & spec in particualr) really chews up render time. Spend some time getting those to behave will really save yourself tons of time in the long run.

I've 25 camera angles to examine diffferent areas from multiple angles & try to make it work over a range of angles. I've over 70 lights of literally every type so far, but most of those are the 3 chandeliers. I laid in some areas lights to start with, then some large IES's thru windows (windows were too small for portals), than a lot of small detail lights such as sconces and small pin spots, etc. I generally work with GI off, but very low Volumetrics to lend some atmosphere to the set. I'll toggle GI to see what it would like to do, then add something specific lighting wise that mimics at a much more efficient render time.

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Tobian
10-03-2018, 03:52 AM
Is your CS set to sRGB? if it's not, yeah you'll get oversaturated bounce light, and dark dark shadows.

Ma3rk
10-03-2018, 03:53 AM
Oh man. I'm slightly brain dead. Here are a couple more angles:

142975

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squeegie
10-03-2018, 05:17 AM
I think I am getting there. I kept the IES lights, adjusted some of the surfaces and re-built some of the geometry. One thing I did notice is that once I subdivided the floor, a lot of the overcast on the ceiling was eliminated ( it was just a big rectangle beforehand).
Very true regarding the surfaces... just the slightest little tweaks and it can go from natural to total garbage.

Now I just need to clean up the scene a bit more and get the render time down ( it took almost 5 hours for this one).

<takes tiny bite and begins chewing slowly>

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Ma3rk
10-03-2018, 10:47 PM
I think I am getting there. I kept the IES lights, adjusted some of the surfaces and re-built some of the geometry. One thing I did notice is that once I subdivided the floor, a lot of the overcast on the ceiling was eliminated ( it was just a big rectangle beforehand).
Very true regarding the surfaces... just the slightest little tweaks and it can go from natural to total garbage.

Now I just need to clean up the scene a bit more and get the render time down ( it took almost 5 hours for this one).

<takes tiny bite and begins chewing slowly>

142977

5 Hours. Ouch. But it is getting there. You probably have something that's chewing up the time besides GI and not really contributing as you might think. You've a lot of moire in the gray dividers panels for example and the floor is a bit too perfectly glossy. Everything else is pretty believable though. If you have something like DAZ or Poser, you might whang together some quick character to throw in & give some it a bit of scale & interest.

My examples were all under 1 hour, but I'm not using GI either.

You might want to dupe your scene & test swapping out the ies's for linears though. No guarantee but it might speed things up quite a bit as you'd have a lot fewer lights, and in this situation will probably look very similar on the walls as what you have now.