Help with Iray Interior Scenes using Mesh Lights

DzFire

 

kyoto kid said:

DAZ_Spooky said:

One other point, more lights, in Iray, equals faster renders. 

...not if they are emissive lights.

Well over a hundered emissive lights here and about 15 minutes to render. No other lights.

kyoto kid

Arnold C. said:

kyoto kid said:

Yeah, really need a GPU with more horsepower to get away from CPU rendering which would speed things up a bit.  Sadly, one that would work well for most of my scenes costs about 1,000$ (the 12 GB Titan-X). 

Was dreaming about a Quadro VCA until I had a glimpse on the pricing, around €45,000,-. After recovering from the followed hemoptysis and 99 nervous breakdowns I got that 8 Titan-X's would be a lot cheaper, providing the same renderpower, 12 GB VRAM and 24,576 CUDA cores, but a mainboard which you could put them onto would still be have to invented.

...well the Quadro M6000 was upgraded to 24GB for the same price as the 12GB version. The VCA still uses the 12GB M6000s. I'd wait until the dust settles with the Pascal release. There is a good chance when the HBM 2 GPUs finally become available along with the right drivers, we could see 12 to 16 GB of video memory on the next generation Titan branded GPUs. with a marked increase in speed. These cards should also have a smaller form factor and loer power reqirement.

dHandle

kyoto kid said:

Tobor said:

kyoto kid said:

Never messed around with IES profiles. Have a couple freebie sets I downloaded but don't know how they need to be installed.

 

I never messed around with EIS profiles either until I saw a couple references to them in another thread, along with links to get freebie sets.  So...I got the free sets then went looking under the light settings to see what I could find.

In both mesh lights and DS lights, there is a setting for "Emission Profile".  It's looking for an .eis file, which is exactly what's in those freebie sets.  They're loaded the same way texture files or bump maps are loaded: click the button on the side of the "Emission Profile" parameter, click "browse", go find where you saved them and pick one.

I had a scene loaded that used 1 mesh light.  I left everything the same, but kept swapping out the EIS profiles to see what effect they would have.  I have 1 set that has something like 70+ profiles in it.  I didn't try them all...maybe 6-8. Not surprisingly, they give different results.

Test Results: Two renders.  One with default settings = no EIS PRofile;

The second with an EIS Profile used.

I have a lot more research to do.  For example, I need to find out what all the settings are on these, and how I can predict what effect they will have in a scene.  Are some profiles directional?  Can the direction of the light be predicted or changed?  What else is involved?

If anyone can point me to more info or maybe a tutorial, I would appreciate it.

 

Fishtales

An IES Profile tells the render engine what 'shape' the light is coming from a given style of bulb.

Have a look through these images.

https://www.google.co.uk/search?client=opera&q=ies+profile+pictures&sourceid=opera&ie=UTF-8&oe=UTF-8

kyoto kid

DzFire said:

 

kyoto kid said:

DAZ_Spooky said:

One other point, more lights, in Iray, equals faster renders. 

...not if they are emissive lights.

Well over a hundered emissive lights here and about 15 minutes to render. No other lights.

...GPU or CPU render?

tring01

DzFire said:

 

kyoto kid said:

DAZ_Spooky said:

One other point, more lights, in Iray, equals faster renders. 

...not if they are emissive lights.

Well over a hundered emissive lights here and about 15 minutes to render. No other lights.

In my experience emissives are super useful to create lit or glowing surfaces, and don't cost much render time when used that way.  When they do cost gobs of render time is when you push the lumens way up so that they light up the scene.  Also, with a very high end machine one can get away with a lot less efficient scenes.

dHandle

Fishtales said:

An IES Profile tells the render engine what 'shape' the light is coming from a given style of bulb.

Have a look through these images.

https://www.google.co.uk/search?client=opera&q=ies+profile+pictures&sourceid=opera&ie=UTF-8&oe=UTF-8

Thanks Fishtales!  I did a little more research using the links you provided.  I learned that in DS, the IES Profiles point straight up when applied to spheres and need to be rotated -90 on the x axis.  I also learned that there are viewers...you can make your own IES Profiles.  It's a lot to take in. 

If you REALLY feel the need to micro-manage your lights, this is the way to go!

I rotated the sphere mesh light in my scene -90 on the x axis and rendered it out.  It looks fairly realistic.  A cone of light pointing down with falloff, etc.  A good addition for adding realism to renders, but I'm sure it will take a lot more practice.

Here are 2 scenes: one with a tight beam of parallel lights pointing down; the 2nd with a broader cone.

tring01

dHandle said:

Fishtales said:

An IES Profile tells the render engine what 'shape' the light is coming from a given style of bulb.

Have a look through these images.

https://www.google.co.uk/search?client=opera&q=ies+profile+pictures&sourceid=opera&ie=UTF-8&oe=UTF-8

Thanks Fishtales!  I did a little more research using the links you provided.  I learned that in DS, the IES Profiles point straight up when applied to spheres and need to be rotated -90 on the x axis.  I also learned that there are viewers...you can make your own IES Profiles.  It's a lot to take in. 

If you REALLY feel the need to micro-manage your lights, this is the way to go!

I rotated the sphere mesh light in my scene -90 on the x axis and rendered it out.  It looks fairly realistic.  A cone of light pointing down with falloff, etc.  A good addition for adding realism to renders, but I'm sure it will take a lot more practice.

Here are 2 scenes: one with a tight beam of parallel lights pointing down; the 2nd with a broader cone.

Very nice.  I have to start experimenting with that next!