Help with fireflies in Luxrender

Hi I am new to Blender Artists and I wanted to ask some help with this car I am rendering in Luxrender. Mainly I want help with how to get rid of the fireflies in the render but also if you want you can critique it if you would like to.


The people over at LuxRender could help you with this a lot more, but usually this happens when there is something a bit too specular or reflective in the scene. Try to stay away from values that are 100% or 1.0, since these values don’t exist in real life. The most specular surface on earth that they use in telescopes isn’t even 100% reflective, but it comes close.

In some cases the type of lighting or integrator can cause this effect, and in other cases you have to let it bake longer. It’s hard to tell what is exactly causing the problem without settings to go on as well.

Well every material is below .5 specularity. There is a Meshlight in the background
(those panels and the headlights) rest of lighting is area lamps. I also added to this the .blend file I used just follow the link( Maybe if you look at the settings you could help a bit more if not I will do what you said and head over to the people at Luxrender. Plus it is my first time really using luxrender for a little project.
Thanks for replying too!

Plus I know the file says Porche Carrera but I only used a diagnal view of the car so it did not come out as good as I had hoped also since i only had a weekend to work on it.

A couple of remarks:

-always use the recommended MLT/Bidir preset (unless you know exactly what you’re doing)
-when enclosing the scene in a black box, switch off all environment lights as any rendering power spent on them will be wasted
-without an environment, it is not actually necessary to enclose the environment
-light sources behind glass will always be slow, consider using the “architectural” glass option
-instead of glossy, try using one of the carpaint presets
-reflection and transmission colour of the glass material can be configured within the material, so there is no need to use a mix material to add reflection
-a specular value of 0.5 is still very high, I recommend 0.25 as the maximum
-an exponent value of 1000000 is pretty high, lowering it should increase rendering speed
-some materials in your model still have extremely high specular values (like 0.89 for the material called YAuLiNA)
-using larger area lights will improve rendering speed

are ‘fireflies’ the hard specular hi-lights…? would it also be correct to call it artifacting?
Sorry Trying to learn the correct terminology :slight_smile:

thanks for the tips
abelabel where did you learn all of this stuff about luxrender?

One more item:
-bump scale is in scene units (meters), so a typical value would be around 0,001.

Mostly on the LuxRender forum and IRC channel and by reading the PBRT book. Most of it should be documented on the LuxRender wiki nowadays.

I have done everything you said and now the picture looks much better but there are still a few more fireflies. I see that when I turn off all of my meshlights the fireflies disappear and when I turn them back on they reappear. Do you know how I can get around those last few fireflies?

I posted in luxrender site a lot of months ago my method to get rid of them:

Imagine you want your render in luxrender at 1000 samples. Instead of that you make two renders each one of 500 samples (so the time is the same but you have two images instead only one). Open gimp (or whatever you want) and load the two images. The above one put it in “darken only” mode at 100%. Flatten the image and done.

You can try to compare this with a 1000 samples render to see if it is valid in your case or not. Of course if instead of using two 500 samples renders you use two 1000 samples or superior you get better quality always.

Thanks for the reply. I did get the fireflies out and the new overall picture looks much better I will post it up when it finishes rendering.

finally got the final picture done, its at
I made two different pictures of it one is the original and the other is one I circled where I would of improved on if I had more time. Plus on the website there is the rough copy of the second version of the Array Project I posted on youtube a year ago which is very much improved on since I learned how to use the compositor and set up a good lighting rig.