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This is a printscreen of a partial rendering. The whole rendering is 8291 pixels width.
When the render was about 3000 the render is full of fireflies and for my eye it seems not getting less when rendering longer
till 5928 s/px at htis point.
It is still busy, but does anyone have an idea if the fireflies can get less while cooking even longer?
I am using direct lighting.
Can I maybe better stop this render and try in pathracing to get a better result?
cheers

Which Kernel are you using currently ? If you are using Direct lighting, you should try with PMC or path tracing (rather PMC).

I would try PT as it's a lot of reflections and glossy surfaces - gut feeling that it will probably be a bit faster than PMC too =)

In my experience some HDRIs produce an awful lot of fireflies (which don't really clear, no matter how long you wait). This seems to be the case here. Try to change HDRI.

In some cases, mapping the environment (LDR image) to reflect onto some surfaces (planes, cylinder or sphere) using a diffuse material with emission can do better than HDRI lighting. And if the emissive material gives too many fireflies, then switch to PMC.

Thanx guys, thnx for your advice.
I'll try the different kernels and also changing hdri and try ldr instead of hdri on this project to learn and see what will get the best result.
I am busy now with other project deadlines (regretfully not in octane cause I am not that good with Octane yet to have it integrated in my workflow), but I will post the results of experimenting with your advice and this project.
For now I satisfied the client by reducing noise in postproduction and resample it to a smaller dimension. The noise that remained (from the many fireflies to start with) was not that obvious anymore.
And the end result of this Octane render in experimenting stage had already more impact than the result I had previous from my rendering in Artlantis... Ofcourse!
I am so happy in getting to know Octane better and better... Very slowly though but I will get there... Surely with the help from you guys on this forum. Super!
Greetings

maybe a really small HDRI its better for ilumination and blurry reflections, when i use HDRI in animation a use to reduce the size a lot and then the render get really faster.

try PMC - it will look a lot noisier to begin with than the others but it will then accelerate in its cleanup way quicker than the other kernels.

also - do 1st image at 8000 samples do a second render of the same image, stop it at about 5000 samples and take both images into photoshop - put the higher sampled image on top of the lower sampled image and use 'darken' on the top image - this will get rid of almost all of the fireflies.
'Darken' will let any bright pixels on the top image use the bottom image - given the random nature of the sampling its unlikely that with enough samples in both images that you will have a firefly in both locations - but if there is you can manually clean up the few there are - I find this is a much better way than using the firefly filter in octane which has a blur effect on the whole image.

Dude, its HDRI image....i have some hdri which produce fireflys and they render really slowly...others works great....
It happens to me all the time....

good luck