A thousand points of light...


jlcDesign
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Hope you guys can help. I can't seem to figure out what wacky circumstance is causing this particular file to process raytraces with a zillion white pixels in it.  I'm sure it has something to do with the lights, but none of them are more than around 60 watts.  Even if I run this to 150 passes, there are still little white pixel fairies (fewer, but still).  Anyone?  Anyone?

weird raytrace.jpg

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it's definitely a light problem. Suspect it is one or all of the point lights. Turn them off and run a quick Ray Trace, you will know in about 3 passes. If it's much cleaner start turning them back on one at a time. You may need to reduce their intensity. If you post the plan I can take a look at it.

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1 hour ago, jlcDesign said:

Thanks Graham!  Here's the plan (dropbox link)...   https://www.dropbox.com/s/6sladq7gjl1q7mp/Jarrell for CA.zip?dl=0 

 

Particularly camera 11 & 12, but it's also done it to me with the ext. views unless I turned off the porch lights (which I did).  Super-weird.

Turn "photon mapping" off in ray trace settings and give it a try

im on the road so I can't say for sure but suspect that's the problem, or rather the culprit.. photon mapping can take a 100 plus passes with multiple lights in a scene 

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I tip my hat to Rene's rendering capabilities and won't argue his advice.  I would like to point out however that turning off photon mapping should not be considered a "solution" but rather a compromise.  IMO you will lose a substantial amount of realism by turning that setting off (may or may not be fine depending on the situation).  The real solution in my mind is to really work on your methods through lots of experimentation by getting a feel for:

 

-Lighting (type, quantity, location, color, intensity, etc.),

-Material settings (this can get very complicated but it is a crucial part of obtaining good looking results) on an object by object and even surface by surface basis.  

-Ray trace settings.  I think it would help greatly to search out and study some of the terminology such as photon mapping, caustics, ambient occlusion, etc.  

 

When it comes to ray tracing I really believe there are no real short cuts.  Every model and even every scene seem to be a little different and bring their own unique challenges. It takes dedication to the art and a lot of practice.  

 

Best of luck.

 

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Thanks Michael.  I appreciate your candor, and kind-of pride myself in some really well-done raytraces.  This is the first time I've been stymied by this type of issue and I don't have more than the usual amount of lighting, but you're right-- I'll have to dig into the advanced settings for ray tracing.  I've been doing this for 15 years.  I guess it's about time :P

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5 hours ago, jlcDesign said:

Thanks Michael.  I appreciate your candor, and kind-of pride myself in some really well-done raytraces.  This is the first time I've been stymied by this type of issue and I don't have more than the usual amount of lighting, but you're right-- I'll have to dig into the advanced settings for ray tracing.  I've been doing this for 15 years.  I guess it's about time :P

Well said to Michael, photon mapping used to be unchecked as a base option, with x9 the setting was checked on default.. I'm not in front of my computer right now so this is out of memory but I believe photon mapping's primary use is to develop caustics and subsurface scattering through translucent surfaces. The more direct light and less ambient light you have, the more difficult it is for the photon mapping to calc.. if you want to keep pushing the rendering envelop you'd really need to play with point lights and material properties as well as exterior point lights. The Particles you see are your computer trying to "find" light coming through windows and slipping into dark corners of rooms or bouncing off of reflective surfaces... when I was using chief for rendering it was necessary to significant play with individual lighting settings, turn up internal ambient light in your 3D dbx. And play with the ambient occlusion settings in your ray trace dbx. After all that was set photon still took a 100 passes to clear the noise

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The problem is the 4 exterior point lights on the garage. For some reason the position of the light within the fixture is incorrect. Open up the light fixture DBX, select Light Data tab, under Offset change the Y Position to -4.

 

Here is a Ray Trace as per the original plan setting. 5 passes.

594e740581897_Untitled1.thumb.jpg.7992ca14b066ff72e0a5aefd8ed6de28.jpg

 

Here is the same scene with the Offset changed. 5 passes.

594e741a44554_Untitled2.thumb.jpg.dcf0e49ded7baac8c2af6f0f1a990d32.jpg

 

Whenever you get speckles it will be related to a light fixture and in most cases it will be a point light. The position of the light source within a fixture is critical, it can't be such that it is occupying the same region as a material. If you resize a light fixture the offset does not adjust to the new sizing and as such you may need to manually make this adjustment. This was not the case here as the fixture is as per the original library model, must have just been an oversight when this model was originally created.

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Thanks Scott. I checked out a few more of those exterior lights in the plan which were originally turned off. They also need to be adjusted. They are the exterior point light fixtures on the back of the house.

 

Existing settings, 10 passes.

594e843775060_Untitled3.thumb.jpg.e4b9528e761dab4d328ddb66c617d9c7.jpg

 

After adjusting the Offset, 10 passes.

594e8461cdec2_Untitled4.thumb.jpg.4c6b2c43daa19ca6dbeb41872ae9e31f.jpg

 

As you can see, it doesn't take much for things to get really screwed up. This plan has 65 lights and if only one of them is not right then everything can be a mess. I have always found this to be those point lights and I really never use them very much, usually convert them to spot lights. Less problems and Ray Traces will run faster.

 

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All of you guys...

giphy.gif

 

I never would have figured it out.  Thanks so much!  Related to lights, anyone got a good lead on some under-cabinet LEDs?  I'm so tired of the big clunky flourescents that CA offers.

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Just curious if anyone (Renerrabbit) any other program for rendering? An Architect, who uses SketchUp, shared an image he did in Render[in] that works inside of SketchUp, like when we take a Full Perspective camera to navigate around our model. You simply open the plugin and turn on the lights and adjust the intensity. You get instance views in realtime. It's amazing!!!!!

 

if only Chief had such a feature?????

 

 

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On 6/23/2017 at 4:16 PM, jlcDesign said:

A million thanks to both of you!

 

giphy.gif

What is with these Grinch hands she has going on here?! The minute I saw this I had to say something. This gif. is a running joke in my house. 

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