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Digital Hermit
10-07-2006, 11:22 AM
Srry... Msg should have read, "How to make a real...?" or "How do I make a real...?" I had two thoughts competing; both won and grammar lost.

Anyway....

I know, you would say, "Just throw a spotlight in a modeled cylinder… right?"

What I am having trouble with is the “base width” of the light (with volumetric) matching the base width of the cylinders projecting lens. Is there anyway to make the base of the light wider? As of now, it looks like a pointy narrow cone emanating from the direct center of the spots lens.

Thanx,

Digital Hermit

*Pete*
10-07-2006, 12:09 PM
have the light more far away from where the real light would be, then have a narrow angle on the spot.

by having the light for example a mile away, and a spot angle on 1-2 degrees, you would get a almost straight, relatively thick, line of light.

the more far away the light is placed, the thicker beam you get.

Sekhar
10-07-2006, 12:55 PM
Is there anyway to make the base of the light wider?
You can set cone base (click on volumetric light options to see this).

Digital Hermit
10-08-2006, 12:55 AM
have the light more far away from where the real light would be, then have a narrow angle on the spot.

by having the light for example a mile away, and a spot angle on 1-2 degrees, you would get a almost straight, relatively thick, line of light.

the more far away the light is placed, the thicker beam you get.

Thanx Pete and Sekhar, I do want a narrow beam, but when I do what you suggested, the light does not go through the spots mesh. Also, the lens flare/glow option goes out the window. The volumetric, however, does show up and, like Sekhar suggested, I did adjust the cone base to match up with spots opening.

To say the least I am puzzled at the lack of spotlight control options and I am thinking, this should be noted as a LW spotlight feature request "cone base width" then it would not be so much of an unnecessary work around that still falls short of the results one needs.

Best regards,

Digital Hermit

Sekhar
10-08-2006, 01:43 AM
The cone base setting *is* for the base width, so I don't understand what you mean... See below for the settings window and renders with width = 0m and width = 1m.

If you're looking for something else, may be you could post your scene?

Digital Hermit
10-08-2006, 07:37 PM
The cone base setting *is* for the base width, so I don't understand what you mean... See below for the settings window and renders with width = 0m and width = 1m.

No, not really, and you have supported my point with your example. The "cone base" setting moves the volumetric "base" forward of the light source. As you can see, that does not have the desired effect in my example. (Spot_01)

When I move the “cone base” setting to match the perimeter of the lens (Spot_02) the width does not match the width of the lens or the spots physical opening

In order to get the width and angle I want, I would have to move the light source back and beyond the boundary of the mesh, in order to match the lens' opening of the physical spotlight. When that happens, obviously, I block the light source.(Spot_03)

Hence, I reiterate the need for a scalable 0m “cone base width” setting. What we have now is a “cone base projection” setting. (or whatever "name" you want to come up with – heh)

Thanx,

Digital Hermit

Sekhar
10-08-2006, 07:52 PM
Move the light as necessary and exclude the mesh from interacting with it (see objects tab in light properties) - mesh won't block the light.

Also, if your goal is to add a light inside the mesh, why not just place the light inside and play with the beam angle instead? Unless I'm missing something...

*Pete*
10-08-2006, 09:14 PM
I think sekhar has the solution for your problem.

as i understand of your screenshots, it is the third image that is what you want to make to work.

try as Sekhar suggested...it goes like this


Clone your light into two and name them like this.

"Spot A"Spot, vith volumetric
"Spot B" Spot, light only.

exclude the lamp and lens from Spot A, but leave the wall to be included.
exclude the wall from Spot B, but leave the lamp and spot included.

use Spot B to illuminate the lens and lamp interior correctly, you will have to position it inside the lamp.

have Spot A behind the lamp, as in image 3.


it should work, but just remember, that if you are going to have more objects in the scene, exclude everything (except lamp and lens) from Spot B.

UnCommonGrafx
10-09-2006, 06:32 AM
Why double up the lamps?

What I've done for that kind of thing is just make the cone area of the lamp extra large and put it inside the lamp. If you have shadow raytracing on the lamp geometry will occlude the light just like in real life.

As an aside, if you want to do as a spot would do, make an endomorph that makes the opening smaller. With this you can change the aperture size of the spotlight and make your light emitted cone smaller based on the spotlight aperture. Again, just like in real life.

Digital Hermit
10-09-2006, 12:53 PM
Thanx for the replies,

For simplicities sake, I tried UncommonGrafx solution first. (Spot_04) is the volumetric and lighting effect I want. Problem is, I want a narrower angle on the beam, but still have it fill the opening of the lamp. I tried the aperture idea (spot_5) and it does as “UCGfx” implied; it works well as a ... well, a spot, with an aperture - heh - but it lacks in filling the opening of lamp.

I have not tried Petes or Sekhar method, but if I follow it correctly - noting the volumetric effect in (spot_4) - wouldn't excluding the lamp mesh for the volumetric lose the edge effect of how the volumetric renders the lamps design?

So, to sum it up, what I want is… the volumetric that (spot_4) is producing, but with a little narrower (not straight) beam...


Reiterating, again, my need for a scalable 0m “cone base width” setting. ;)

Regards,

Digital Hermit

UnCommonGrafx
10-09-2006, 01:04 PM
So change it to another light type!
;)

UnCommonGrafx
10-09-2006, 01:17 PM
Oh, and with that large an opening why would you expect a narrower beam? Not gonna happen. That's why you need an aperture control or to narrow the opening of your light hood.
A 'real' looking spot would behave as such.

Also, don't forget to learn the old skool methods: a cone with transparency applied. Do a google for more.

Sekhar
10-09-2006, 01:55 PM
By narrow, I think he means less diverging, but still matching the lamp opening. Kind of like a PAR, where the light beam is almost parallel.

Digital Hermit, I feel your best bet is to change the cone base width (or whatever you want to call it) and move the lamp back, excluding the lamp housing (as I suggested). If you want the lamp mesh to interact with the beam, separate the mesh to another layer and don't exclude that. Alternatively, you can use the projection image option for spotlight to create a throw pattern.

I know you want a light feature that allows you to effectively resize the lamp, but we have to work with what we have. LW does allow resize for linear and area lights though, FYI.

UnCommonGrafx
10-09-2006, 02:48 PM
Post the test scene so we can dazzle you with our brilliance. ;)
As well, show you the versatility with which this can be accomplished.

Stooch
10-09-2006, 03:56 PM
here you go. pretty self explanatory, might come in handy.

the spotlight has volumetrics enabled, all settings default otherwise.

I would imagine that you can simply put a camera inside the aperture and render, then use the alpha pass as your armature shape.

by the way, incase you didnt know there is a cone base attribute i the volumetric options, that let you decide where the volumetrics start in relationship to the light, so you can move the light and cone angle to what you want and then play with the cone base setting. anyway take a look for yourself its pretty straight forward.

Thomas M.
10-10-2006, 03:23 AM
One point I hate about LW's spotlights is the outdated kind of falloff. You can specify the inner and the outer light circle and inbetween there's kind of a linear falloff.

Why can't NT give us a curve/gradient which specifys the distribution of light within a 180/90 angle? LW's spotlight is pretty un-photorealistic. It wouldn't cost too much to change this. Also I would like to see area lights with a double-sided/single-sided option. In a photostudio I've never seen a waver/softbox which shoots light in both directions. Really wired.

Cheers
Thomas

kmaas
10-10-2006, 06:03 AM
Also I would like to see area lights with a double-sided/single-sided option.

Here here! :agree: