Forum: Poser - OFFICIAL


Subject: How do I simulate torch light in an inclosed space?

75oroboy opened this issue on Apr 02, 2013 · 26 posts


75oroboy posted Tue, 02 April 2013 at 11:49 PM

Hi everyone, I'm a newb to Poser (more specifically Poser Pro 2012), and purchased a scene prop from the marketplace called "The Pit." It's a great set, but I wanted change it up a bit by adding some of my own stuff.

One of the things I wanted to add was torches along the wall of the cave, and simulate the way torch light would spread from it's source, to a few feet in every direction; with the light being the brightest on the wall right behind the torch.

I was able to achieve this look by using a point light over a torch prop. As shown in my preview render... it's was a bit misleading to me, because when I did a render using FireFly, the look I thought I had from the preview render, became totally flat in FireFly (see second pic).

There is one other point light (with a light-blueish hue) above the camera/rendering area, with an intensity of 40%. The point light on the torch is at 100% intensity. I've also attached my render settings for FireFly.

The only parameter I touched on the torch light was Dist End; which I set to about 35. All of the rest of parameters as well as the properties for the point light are at default settings.

Can anyone help shed some 'light' on the subject? Thanks in advance!

Preview Render:

FireFly Render:

Render Settings:


LaurieA posted Wed, 03 April 2013 at 12:05 AM

Well, you'll definitely want to use indirect light. It's a more realisitic looking lighting. You may either want to put a very dim point light behind the torch (inverse square falloff) or use a glowing material for the torch. Plug the texture for the torch into the ambient channel in the material room and start with a value of something low like 1.0 and build up until you get the effect you're going for :). Personally, I'd mix the two.

Laurie



Zanzo posted Wed, 03 April 2013 at 1:16 AM

What Laurie said although I've never used ambient before, i've always used point lights for such a thing. The question is which one is better? That ambient light technique or the point light?

Start with a simple point light with a distance of like 5 with low light strength and raybased shadows at 1.0 and tweak it from there. Mess with the light strength, distance, shadow settings and color.

Reference images help.


PrecisionXXX posted Wed, 03 April 2013 at 1:31 AM

As Laurie said, a point light for each torch, don't use the dialed falloff, leave that at zero, in the properties for the light, set inverse square.  For a torch, probably take some blue out, torch light is more reddish or yellowish.  Adjust intensity until it looks right.

Doric.

The "I" in Doric is Silent.

 


75oroboy posted Wed, 03 April 2013 at 2:37 AM

Laurie and Zanzo, thank you both very much for replying very quickly; I really appreciate it!

Laurie, being new to Poser, I wasn't sure what you meant by "inverse square falloff," but I already do have a point light situated above the torch; so I lowered that down to 50% intensity, and did a render with indirect light turned on like you suggested. Once again, I'd like to note that I have also have a point light in the ceiling of the cave (@ 40% intensity w/blueish hue)... I don't know if that extra bit of info is useful or not.

This is the result I got with just a Point light w/50% intensity:

 

Next, I did as you recommended Laurie, and mapped the texture of the torch tip to the ambient color node; and gradually adjusted the ambient value. The point light is still situated on top of the torch, so I'm using both light sources at this point, as you suggested... and this is what I got:

 

I wanted to try the amb. value at a higher number, so I kept going up by 50 everytime; after hitting a value of 200, I got a look that I liked from the torch, but now there were shadow artifacts (splotchy spots) being emitted everywhere on the wall, ground, and other objects in the scene. It looks as if I put a multiplied layer of an indifference cloud from Photoshop over the scene:

 

The above render has an amb. value of 500. I really like the way the torch came out, but now the surrounding area has a 'splotch' look to it... almost the same look as flashing a light through a camaflouge net onto a wall. Is there anyway to get rid of the shadow artifacts, but keep the intensity of the light/ambient light? If not, I guess I'll have to try a happy medium, and do some post work in Photoshop.

I'm getting closer to the look I want though... thanks for the help Laurie!


75oroboy posted Wed, 03 April 2013 at 2:43 AM

Doric, thanks for that extra tip... I wasn't sure what Laurie meant by inverse square, but your little hint of it being in the properties tab got me searching; finally finding it in the Attenuation drop down menu. Thanks for that, and the tip about putting the dialed falloff back to zero. I'll try adjusting the point light with those attributes changed.


Zanzo posted Wed, 03 April 2013 at 3:32 AM

What does it look like with no ambient and just the point light?

What does it look like with ambient and no point light?

I'm curious :)


75oroboy posted Wed, 03 April 2013 at 5:02 AM

Thank you everyone! I finally have achieved more or less the look I was after... now it's just a matter a fine tuning the settings. That tip about the inverse square solved pretty much the problem I was having. I'll probably end up photoshoping some flames in, but overall effect on the walls on floor is what I was truly after. I really appreciate all of your help!

Zanzo, to answer your questions:

No ambient, just a point light (30% intensity):

Just ambient, no point (ambient value:100)

Just ambient, no point (ambient value:500)

Combination of both (Point, 30% intensity; Ambient Value: 100)

Both just the point light, and the combination of both appeal to me; or rather, specifically the way the torch head looks. I'll probably go with the combination, and do a little post Photoshop work. Thanks for the help guys, especially you Laurie!


Zanzo posted Wed, 03 April 2013 at 12:49 PM

I appreciate you taking the time to show those renders.

Regarding Flames... This actually works quite well, instead of having to add the flames in the scene, you can just add them afterwords in photoshop or something.


75oroboy posted Wed, 03 April 2013 at 2:41 PM

Quote - I appreciate you taking the time to show those renders. Regarding Flames... This actually works quite well, instead of having to add the flames in the scene, you can just add them afterwords in photoshop or something.

I appreciate you folks giving me help, it's the least I could've done... cheers!


seachnasaigh posted Wed, 03 April 2013 at 4:14 PM

     For things with a relatively great brightness and relatively small size, such as flames, light bulbs, etc., I recommend that you use a combination of a point light (set to inverse square attenuation) with IDL using an ambient mesh item. 

     But...   For things which are intensely bright relative to their size, Firefly's IDL will not react in correct proportion.  Look at the render with the ambient of the flame set high;  nothing but a flat white silhouette.  So, try giving the visible flame a gentle ambient (0.67 or so) and using an emitter prop which remains unseen but has very high ambient (Firefly seems to top out at about ambient=32).  I also like to have another prop with a softened shape surrounding the flame which will provide that "glow" effect.

Tink Christmas.

"Harley" plushie by Littlefox at RDNA

"Noel tree" by Pretty3D at R'osity  (IDL kit by me)

"MyLantern" lantern 8 by Judibug at R'osity (IDL kit by me)

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5


seachnasaigh posted Wed, 03 April 2013 at 4:35 PM

     Square lamp shade with its surrounding aura (note smoothed shape of aura), and a lightbulb with surrounding aura, which follows the shape fairly closely because it's already rounded:

box lamp shade.     lightbulb and aura.

     In both cases I did not show the emitter mesh, because the emitter would simply be a "shrinkwrap" overlaid onto the visible prop.  The aura mesh seems large, but the "glow" you'll see when rendered will only extend out about half the distance of the mesh.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5


seachnasaigh posted Wed, 03 April 2013 at 4:57 PM

      Belatedly, I note your recent "joined" date.  If you don't model (yes? no?), you can still do this.  Load a primitive prop, either the sphere or the capsule, whichever most closely fits the shape of the flame in the torch.  Move it to surround the flame, and scale it to contain the flame, preferably without intersecting the wall.  That will be your emitter.  Now Use edit: duplicate ball_1 to make another sphere, and scale it up about 150% to 200%;  this will be the "glow" aura.

     In the parameters panel, click the properties tab, and for the emitter, untick both the casts shadows box and the visible in camera box.  For the glowing aura prop, untick the casts shadows box.

     I'll need to make some screenshots to help explain and make material files for you.  Check back later.

edit:  On further thought, please post a screenshot of a preview closeup of the flame part of the torch, showing also the end of the non-burning shaft.  It may be simpler for me to make a substitute torch end, with emitter and aura.  ^^

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5


75oroboy posted Thu, 04 April 2013 at 6:37 PM

Seachnasaigh, thanks for the tip about the glow; and sorry for the slow reply back. I did as you instructed, and loaded 2 primitive capsules (my torch prop locks like a matchstick), and followed your suggestions; it's just that I don't know which shaders I should assign to each capsule (inner & outer).

I appreciate you taking the time to go through all the trouble of explaining the glow method to me, it was quite interesting, thanks!


seachnasaigh posted Thu, 04 April 2013 at 9:53 PM

     I have re-read your posts, and now realize that the torches are separate from the "Pit" prop set.  This greatly simplifies things.  I've whipped up a model in Silo which consists of the torch, wall braces, flame, IDL emitter, and glow aura.   My workstation Cameron is cogitating on a test render now.  Once I get the materials adjusted to my satisfaction, I can zip this torch up and post it as a freebie.   Just load and render!  ^^

     Nonetheless, I'll make material room screenshots for explanatory purposes.  Meanwhile, here's a Silo screenshot of the torch assembly.  The torch will lean out from the wall at a 30' angle, that's why the flame is bent.  Yeah, I know, it looks more like a jalapeno pepper than a flame. :laugh:  I'm counting on Poser material work to make it render like flame ... hopefully.  The bigger chicken-wire looking thing will provide the glow;  the glow will only extend out from the flame about half as far as the chicken wire.  Again, I'm hoping it looks better rendered than it does here. :rolleyes:

torch.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5


75oroboy posted Fri, 05 April 2013 at 12:49 PM

Nice work Seachnasaigh! Seriously though, take your time; I'm in no rush to finish anytime soon on the project, as it is just a hobby. So don't feel like you to rush to get it to me as quickly as possible... and I really do appreciate your help!


seachnasaigh posted Sat, 06 April 2013 at 5:52 PM

     Oh, I just do Posering in between real world work, myself.  ^^  Here are proof-of-concept renders of the torch.  I'll stress that using a mesh object for IDL illumination is an addition to Poser's lighting arsenal, not a replacement for lights.  You can see that a weak point light (inverse square attenuation) would improve this.  The point light should be placed inside the flame, near the top, and a bit outboard from the wall because the wick-wrap portion of the torch will cast shadows.

Tomb Raidertorch closetorch closer.

     In the shot which shows two torches, note that they are not identical;  The flame ripples and the wood grain of the staffs are different, by simply nudging the U offset and V offset.  Simple and resource (RAM) economical.  :)     I should make some .mt5 and .mc6 material files so that folks using several torches can easily make them unique.  I anticipate doing this, stripping out the geometry from the prop file, and packing a zip this evening, and uploading to R'osity freestuff.  It may take a day or so after that for it to clear R'osity QC and appear in freestuff.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5


seachnasaigh posted Sun, 07 April 2013 at 2:46 AM

     The torch zip has been uploaded to the R'osity freestuff area;  it usually takes about a day for approval before it will appear for download.  We can hum Girl From Ipanema while waiting. :laugh:

     I figured out how to insert render instructions in the metadata. :biggrin:     If you have your library set to show the item details panel, you get instructions! :tongue2:

xmp.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5


hborre posted Sun, 07 April 2013 at 6:48 AM

That is awesome.  Thanks for all the hard work.  I can see this item getting quick a bit of usage.


75oroboy posted Sun, 07 April 2013 at 1:15 PM

Quote - That is awesome.  Thanks for all the hard work.  I can see this item getting quick a bit of usage.

Indeed. Seachnasaigh, you've gone up and above the call of duty on this one... I didn't expect this sort of support; thank you very much for all the work you put into this, and for helping me. I will definately be downloading your file! Too bad this forum doesn't have a rep system, I'd definately send some rep points your way... cheers!


DarkElegance posted Sun, 07 April 2013 at 1:33 PM

Quote -      Oh, I just do Posering in between real world work, myself.  ^^  Here are proof-of-concept renders of the torch.  I'll stress that using a mesh object for IDL illumination is an addition to Poser's lighting arsenal, not a replacement for lights.  You can see that a weak point light (inverse square attenuation) would improve this.  The point light should be placed inside the flame, near the top, and a bit outboard from the wall because the wick-wrap portion of the torch will cast shadows.

Tomb Raidertorch closetorch closer.

     In the shot which shows two torches, note that they are not identical;  The flame ripples and the wood grain of the staffs are different, by simply nudging the U offset and V offset.  Simple and resource (RAM) economical.  :)     I should make some .mt5 and .mc6 material files so that folks using several torches can easily make them unique.  I anticipate doing this, stripping out the geometry from the prop file, and packing a zip this evening, and uploading to R'osity freestuff.  It may take a day or so after that for it to clear R'osity QC and appear in freestuff.

oh that is perfect for what I was working on!

https://www.darkelegance.co.uk/



Commission Closed till 2025



seachnasaigh posted Sun, 07 April 2013 at 10:49 PM

     Thank you, friends!  ^^     The torch is now up, in the freestuff area.  :)

     Mea culpa - I erred;  corrections follow!  Cameron finished a test render using a supplementary point light for each torch, and I saw splotchy IDL artefacts, which I suspect are due to some interaction between the point light and the -very close- flame or emitter surface.  I moved the point light a bit to avoid mesh contact, and the artefact disappeared.  So, disregard the coordinates for point light placement which are in the ReadMe and the metadata.  Instead, load a torch into the scene (don't move it yet), create a point light (unsaturated yellow-orange color), and place the point light at X=0, Y=0.775, Z=0.230     Parent the point light to the torch.  Now you can place the torch wherever it needs to go.

pt lt.

     Self-luminous meshes cast light, but they it lacks specular highlights.  Using both an IDL emitter mesh and a point light gives better results than either method used alone.  Mesh lights spread light more like a real world object (even a light bulb does not emit light from a single point);  point lights add specular highlights and can boost the strength of your mesh light.  Specular adds a sense of depth to the shape of 3D objects.  Here are new test renders with a point light added to each torch:

Tomb Raider.     torch closeup.

 

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5


PrecisionXXX posted Sun, 07 April 2013 at 11:25 PM

Every time I see someone trying for flame effects, I think of this.

http://runevision.com/3d/include/particles/

and wish there was some way to get the SDL into Poser, but there ain't.

Darn.

Doric

The "I" in Doric is Silent.

 


DarkElegance posted Tue, 09 April 2013 at 4:59 PM

Quote -      Thank you, friends!  ^^     The torch is now up, in the freestuff area.  :)

     Mea culpa - I erred;  corrections follow!  Cameron finished a test render using a supplementary point light for each torch, and I saw splotchy IDL artefacts, which I suspect are due to some interaction between the point light and the -very close- flame or emitter surface.  I moved the point light a bit to avoid mesh contact, and the artefact disappeared.  So, disregard the coordinates for point light placement which are in the ReadMe and the metadata.  Instead, load a torch into the scene (don't move it yet), create a point light (unsaturated yellow-orange color), and place the point light at X=0, Y=0.775, Z=0.230     Parent the point light to the torch.  Now you can place the torch wherever it needs to go.

pt lt.

     Self-luminous meshes cast light, but they it lacks specular highlights.  Using both an IDL emitter mesh and a point light gives better results than either method used alone.  Mesh lights spread light more like a real world object (even a light bulb does not emit light from a single point);  point lights add specular highlights and can boost the strength of your mesh light.  Specular adds a sense of depth to the shape of 3D objects.  Here are new test renders with a point light added to each torch:

Tomb Raider.     torch closeup.

 

I did this and the point light keeps dropping to near the floor...is that right?

https://www.darkelegance.co.uk/



Commission Closed till 2025



seachnasaigh posted Wed, 10 April 2013 at 3:21 AM

(DarkElegance) 

Quote - I did this and the point light keeps dropping to near the floor...is that right?

        No, something's wrong there.  Place the point light to the position (relative to flame, emitter, and aura) as shown in the diagram.  If you change the preview mode to outline, and switch between the front and left camera views, it will make it easier to move the point light into place.

     Did you type in the coordinates for the point light as given?  Did you parent the torch to some Prop/figure? shrug

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5


seachnasaigh posted Wed, 10 April 2013 at 4:46 AM

     Oh, and what display units are you using?  (I use Poser native units)

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5