Hello everyone,
I came up with a solution on how to deal with Fireflies and Black pixels created by Cycles automatically! All the magic happens in the compositor.
If you have any further information on why they appear and on what you can do about it in general, please post it in he comments. though, with this technique you will no longer have to worry about tham at all!
Hope you enjoy it!
There is one other thing i’d like to mention: Certain material-combinations generate a hideous amount of fireflies. It’s not possible to get rid of them with this technique, because quite often there are two or even more bright pixels right next to each other! Things to look out for are mixing glossy / glass shaders and velvet / glossy. If you know about others please post them.
Furthermore, i noticed that fireflies appear more often when using lamps instead of meshes with an emit value, especially point lamps and area lamps. Anyone made similliar experiences?
thanks for this post, this has saved me a lot of problems, awesome job.
My tip to avoid fireflies is to use only Mesh Emitters, Area Lights are terrible for fireflies - the main cause.
That is indeed so - But there’s allways a chance of having a few of them in your scene, no matter what - hope that will change at some point!
That’s genius! I’m impressed. I would probably never have thought of that. 
Nice to hear that 
I’m just glad i can finally render animations without caring about that issue^^
Blender Tutorial | How to deal with Fireflies and blackpixels AUTOMATICALLY -> Cycles
Ok. Where is the tutorial about this? I watched the youtube movies but is all about modelling and rendering.
hmmm theoretically if you press play on the video in the first post, the video should start right away!
Otherwise just use this link to the video:
hope it works out!
Thank you. Now is working.
Also, the fireflie-count in your scene is abnormally high - do you use lamps? if so, try mesh lighting, usually helps!
The model can be downloaded as a zip archive. I intend to publish it under CC-BY-SA over at BlendSwap when it is finished.
I checked out my idea with the two rendered images with different seeds. The fireflies do not appear at the same spots.
I further checked out the Cycles documentation at the wiki. There seem to be some settings (‘No Caustics’, ‘Clamp Samples’) which might also prove helpful.
Besides a sky texture I use a simple plane mesh at a large distance with high intensity to simulate the sun (sharp shadows).
Dear hotzst,
I checked out your file and the solution is quite simple: The fireflie you get in your scene are not the same ones i talked about. If you uncheck caustics, none of them appear. The problem with caustics is, that cycles handles them horribly at the moment. There are actually two tracker types that would solve the issue i believe, but they have yet to be implemented. Right now i’m rendering your scene WITH caustics on my gtx 590, until the caustics will look good ( probably over night), because i really want to see if they improve at all Also keep i mind that sometimes glossy/glass can give you issues, doesnt seem to be the case here though!
Dear hotzst,
after 10000 samples i noticed that this doesn’t lead to anything ^^ so heres the result. you can see that those weren’t fireflies. only the two remaining white dots are fireflies, and they can be removed as shown above!
I figured out another way to get rid of them: Setting the clamp to about 1 gets rid of them. Values lower than 1 do not work that good. With a value of one the render loses a bit of its brightness, witch is acceptable in this case and adds some more noise, so I need a few more passes. The higher the value the higher the resulting noise and the higher the light absorption.
I will have to try to render without clamp.
As you suggested, the “No caustic” is another option. The quality is about the same as with a clamp of 1, but without the reduction of lighting. So I will go with that option
Thank you!
You’re welcome
I’ve followed the video and yes the translate option is by far the better even if in 2.63.14 I did not had to make all nasty trick with invert/rgb curve I think they fixed up things.
My node setup is much simpler
@Amadeo: Sorry, I had no time to see the Amadeo’s video, yet (I hope evening I get to it). So this note is just note about one really easy way . . .
@elaser: I’m using almost the same setup for quite a long time. Just Laplace Filter is separator. Instead of replacing translation node Fast Gauss Blur works for me too.
Anim GIF (link to FullRess http://blender.howto.cz/blender-links/Fireflies/NODE-FireFlies-result.gif )
Blend
NODE-FireFlies (NoiseReduction).blend (336 KB)
