Emitters as lights

Forums: Emitters as lights
Poser (Integrated Plugin developed by Paul Kinnane)

Moderator: face_off

Forum rules
Please keep character renders sensibly modest, please do not post sexually explicit scenes of characters.

Re: Emitters as lights

Postby gsfcreator » Tue Apr 10, 2018 8:27 am

gsfcreator Tue Apr 10, 2018 8:27 am
so much to learn...thanks, wimvbd!

another question regarding emitters: in poser, if i create spot light, I can cotnrol the angle of the beam easily. what specs are responsible for those values within the octane renderer?
Core I7-8700K, 32RAM, GTX1080Ti, win10
gsfcreator
Licensed Customer
Licensed Customer
 
Posts: 103
Joined: Sat Mar 31, 2018 9:45 pm

Re: Emitters as lights

Postby wimvdb » Tue Apr 10, 2018 10:08 am

wimvdb Tue Apr 10, 2018 10:08 am
Ok, lights, time for a new lesson.

First you need to know that light emitters emit light in the direction of the normals of the mesh. So a one sided plane has one side which emits light, a 2 sided plane emits light in 2 directions, a sphere in all directions.
When you create an emitter from a Poser spotlight, it will create a one sided plane parented to the spotlight. You can control the direction by rotating and moving the Poser spotlight. The one sided plane will follow.

If you look at the material of the material of emitter, you can see it is a Diffuse materal with an Emission section. There are 2 types of emissions: Black Body and Texture emission. Black Body emission uses the temperature in Kelvin to define the light. See https://en.wikipedia.org/wiki/Color_temperature for a list of this with its color. The texture value and power here are multiplied and define the strength of the emission.
For Texture Emission the texture node defines the color of emitted light and is multiplied with power. No matter the texture color, the light will be white very soon if you increase power. It is very useful if you have something like a tv screen. Set up the texture node with the screencap of the monitor and set the power very low (less than 1 normally) and you will have a tv screen which emits a little bit of light.
Surface brightness on makes an emitter independent of its size (mesh size), double sided on overrules the normal direction settings and emits the other side as well.
Sampling rate defines the importance of the light - increasing it makes the render use more samples for it. Visible on or of on Diffuse and specular defines whether the light is seen on diffuse or speciular/glossy materials (normally you have these enabled).
Transparent Emission tells the render engine it should cast light even if the opacity is set to 0 (completely transparent). Cast Shadows Off turns off Shadows.

The distribution Node is the interesting one for how light is distibuted (falloff,, sharpness, etc).
By default lights, are emitted in all directions from each normal (so 180 degrees). You can control this by using IES distribution maps. An IES map is an industry wide standard (with CG and in the real world) to defiine how lights behave. See a tutorial on this here: http://www.cgarena.com/freestuff/tutori ... ieslights/
Load an IES map (RGB texture node) in the distribution node. Set the gamma to 1. Now expand the projection node for the texture and set the coordinate space to Normal Space. (This is REALLY important otherwise it will not work)
iesnode.jpg


That is it.

That tutorial link tells you have to look at the maps and how to create them. In this link https://support.solidangle.com/display/ ... tric+Light there is a link with a set of very nice IES lights. Download the sample picture of it as well, it is handy to have to know what each of the IES maps do. Number 29 for instance is a nice spotlight with defined soft edges.

You can find IES lights in lots of places, just google them. You can often download them from real world lighting manufacturers as well.

Success
Configuration: Windows 10 64bit Creators Edition, I7 6850K, 128GB, 2 GeForce 1080ti, P11 Pro SR6
wimvdb
Licensed Customer
Licensed Customer
 
Posts: 312
Joined: Sat Sep 22, 2012 2:03 pm

Re: Emitters as lights

Postby gsfcreator » Tue Apr 10, 2018 5:15 pm

gsfcreator Tue Apr 10, 2018 5:15 pm
wow. now that' a big lesson :) I've never used IES. Reading the tutotial, thanks! which option should I pick in order to use an IES map? RGB image?

IES.png


Look at this:

https://www.renderosity.com/mod/bcs/?ViewProduct=124045

I've purchased this figure, but I can't seem to replicate the realism that the vendor produced (see content advisory images. I already contacted him also for some advice.) the texture just doesn't comes out the same. are there any tweaks to be done also for that within the OR?
Core I7-8700K, 32RAM, GTX1080Ti, win10
gsfcreator
Licensed Customer
Licensed Customer
 
Posts: 103
Joined: Sat Mar 31, 2018 9:45 pm

Re: Emitters as lights

Postby gsfcreator » Wed Apr 11, 2018 5:11 pm

gsfcreator Wed Apr 11, 2018 5:11 pm
also, can anyone explain to me how can I use HDRI as light within octane render, and what controls the Attenuation for the OR Emitters?

thanks <3
Core I7-8700K, 32RAM, GTX1080Ti, win10
gsfcreator
Licensed Customer
Licensed Customer
 
Posts: 103
Joined: Sat Mar 31, 2018 9:45 pm

Re: Emitters as lights

Postby face_off » Wed Apr 11, 2018 10:35 pm

face_off Wed Apr 11, 2018 10:35 pm
It would be worth you taking a look through the manuals at https://docs.otoy.com/Portal/Home.htm. There are also a heap of tutorial videos in the Videos tab.

Paul
Win7/Win10/Mavericks/Mint 17 - GTX550Ti/GT640M
Octane Plugin Support : Poser, ArchiCAD, Revit, Inventor, AutoCAD, Rhino, Modo, Nuke, DAZ Studio
Pls read before submitting a support question
User avatar
face_off
Octane Plugin Developer
Octane Plugin Developer
 
Posts: 13557
Joined: Fri May 25, 2012 10:52 am
Location: Adelaide, Australia

Re: Emitters as lights

Postby gsfcreator » Thu Apr 12, 2018 6:33 am

gsfcreator Thu Apr 12, 2018 6:33 am
face_off wrote:It would be worth you taking a look through the manuals at https://docs.otoy.com/Portal/Home.htm. There are also a heap of tutorial videos in the Videos tab.

Paul


I'm going through the PDF thoroughly.

there seems to be no videos for poser in the videos tab:

novideosforposer.png
Core I7-8700K, 32RAM, GTX1080Ti, win10
gsfcreator
Licensed Customer
Licensed Customer
 
Posts: 103
Joined: Sat Mar 31, 2018 9:45 pm

Re: Emitters as lights

Postby face_off » Thu Apr 12, 2018 7:53 am

face_off Thu Apr 12, 2018 7:53 am
I lot of the questions you are asking are generic Octane questions - so the Octane Standalone videos will help you.

Paul
Win7/Win10/Mavericks/Mint 17 - GTX550Ti/GT640M
Octane Plugin Support : Poser, ArchiCAD, Revit, Inventor, AutoCAD, Rhino, Modo, Nuke, DAZ Studio
Pls read before submitting a support question
User avatar
face_off
Octane Plugin Developer
Octane Plugin Developer
 
Posts: 13557
Joined: Fri May 25, 2012 10:52 am
Location: Adelaide, Australia

Re: Emitters as lights

Postby gsfcreator » Thu Apr 12, 2018 2:51 pm

gsfcreator Thu Apr 12, 2018 2:51 pm
face_off wrote:I lot of the questions you are asking are generic Octane questions - so the Octane Standalone videos will help you.

Paul


Thanks, Paul, I'm on it.

I'v bumped into another issue with Emitters: I've noticed that if i choose to set the emitter as invisible (within my poser preview scene) - it will also won't show up in the octane Render. that's a bit of a problem, since I tend to also create camera lights (A light that is parented to a camera), and than the Emitter prop gets in the middle of the vision in preview, so I have to turn visibility off, work on my scene, than set it back to visible when I open the viewport. setting the opacity within OR won't help. is there a way around this? (setting emitters to be invisible in poser but still cast lights when I open the viewport and render, just like poser lights behave?)

Emitteropacity.png
Core I7-8700K, 32RAM, GTX1080Ti, win10
gsfcreator
Licensed Customer
Licensed Customer
 
Posts: 103
Joined: Sat Mar 31, 2018 9:45 pm

Re: Emitters as lights

Postby wimvdb » Thu Apr 12, 2018 4:27 pm

wimvdb Thu Apr 12, 2018 4:27 pm
Move the one sided plane behind the camera
Configuration: Windows 10 64bit Creators Edition, I7 6850K, 128GB, 2 GeForce 1080ti, P11 Pro SR6
wimvdb
Licensed Customer
Licensed Customer
 
Posts: 312
Joined: Sat Sep 22, 2012 2:03 pm

Re: Emitters as lights

Postby gsfcreator » Tue Apr 24, 2018 4:12 pm

gsfcreator Tue Apr 24, 2018 4:12 pm
Another question regarding lighting in octane:

I started to figure out that octane lights do not behave as poser lights. its more realistic, so I'm starting to think like the photographer in me.

If i scale up a scene X10 times, that means I need to scale also the size of the emitters AND increase the power X 10 times as well to achieve the same results as in normal size, right?

also, what's the fastest way to create a reflector like object in octane? I created a box in poser and changed the XYZ so it will become a thin, white rectangle. Now i want it to reflect only the lights in the scene, so it will become a reflector without emitting light on its own. I need to know how to tweak that in octane.

appreciate your kind help, people <3 :)
Core I7-8700K, 32RAM, GTX1080Ti, win10
gsfcreator
Licensed Customer
Licensed Customer
 
Posts: 103
Joined: Sat Mar 31, 2018 9:45 pm
Previous

Return to Poser


Who is online

Users browsing this forum: No registered users and 1 guest

Sun Nov 17, 2019 12:38 pm [ UTC ]