Persistent white fireflies in only some indoor environments without HDRI background

Anxaer

Hey there,

so I know people ask a lot about fireflies and usually they have it because there's not enough light in the scene or that there haven't been enough iterations. However, I'm running into a problem with a few indoor enviroments in which no matter how many lights I place or how many textures I reduce- or objects I remove, there are always these white little fireflies around. 

Yes, I could wait much longer than I usually do and complete the render with more iterations but given I can render a similar scene with 10x less the iterations and no grain at all, I feel like it has to be something else or am I wrong? I just thought that these white fireflies might be caused by an issue in either the surface tab or the render settings, could that be true?

Here are two pictures of the same room, one relatively low light and full of furniture, you can obviously say it's so much grain because of that, second one is with all furniture removed and the scene lit. Why are there still so many of these white fireflies? (As enviroment mode I have scene only selected so it can't be from incoming HDRI light either.

Thank you!

Doc Acme

Those don't look like fireflys but rather simply not enough iterations.  Beyond that, hard to tell what render settings are coming into play

In the meantime, try a spot render on small area, maybe just above the dresser.  Let it go to completion & see what that gives you.

You might even try just try resetting the render settings to Default to help suss things out. Often quicker.

 

SpottedKitty

Have you tried increasing the level of the lights and reducing the Tone Mapping settings (in the Render Settings pane) to match? Your render runs with the same apparent light levels, but the scene now has a lot more light rays bouncing around inside it. If the problem is not enough light, that might help.