Animation Flicker Free setting Problem

[Giulia91]

Hello Everyone,
I use 3dsmax with corona and i've been working on a interior animation for the past 2 weeks but when i finally finished and switched  the UHD Cache render settings to "Flicker free"  i noticed that everything  looked much more darker then with the "still frame" render present.
Is this possible or am i doing something wrong? i attached 2 images to better understand.

thank you so much in advance

[GeorgeK]

Hello Everyone,
I use 3dsmax with corona and i've been working on a interior animation for the past 2 weeks but when i finally finished and switched  the UHD Cache render settings to "Flicker free"  i noticed that everything  looked much more darker then with the "still frame" render present.
Is this possible or am i doing something wrong? i attached 2 images to better understand.

thank you so much in advance

Did you use "Calculate from scratch" for precomputation, or load, load + append? Did you make any changes in scene lighting, Performance settings?

Can you please clarify which version of Corona renderer and 3ds max you are currently using?

[Giulia91]

Hello! Thx for the reply,  i'm using 3dsmax 2019 with corona Version  4 . I did'nt change anything in the scene befor switching to render flicker free nor any settings in the performace tab, everything is set by default yet when i change the preset all the lighting seems to change.
The Uhd Cache is set on calculate from scratch

[maru]

The "flicker free" preset is more precise than the "still image" one, so it should give results closer to pure path tracing.

[Nejc Kilar]

The "flicker free" preset is more precise than the "still image" one, so it should give results closer to pure path tracing.

Just out of curiosity, so such lighting changes are expected when switching between the two? Seems fairly drastic in this particular scene.

[maru]

The "flicker free" preset is more precise than the "still image" one, so it should give results closer to pure path tracing.

Just out of curiosity, so such lighting changes are expected when switching between the two? Seems fairly drastic in this particular scene.

I am not really sure, however if you don't use the "flicker free" preset, the animation may end up flickering, which means that each frame has different brightness. That's probably what we are observing here.
How drastic the difference is depends on multiple things, like the lighting and number of reflective surfaces.

[Giulia91]

thank'S  to everyone, i really have no idea what is happening but it's very strange at this point and yes, it happens only when i change between the two presets :( the first image i uploaded is with the still image preset and the second with the flicker free.
maybe i'll try and use the still image preset but saving only one UHD cache and using it for all frames

[maru]

What is the result if you switch to Path Tracing only and let it render a bit longer? (Path Tracing as both the primary and the secondary solver)

[Giulia91]

just tried and still looks dark :(

[TomG]

This would mean that the dark is the more correct version, if that's what full path tracing does - the "speed up" for still frame is a less accurate UHD Cache, so it's brighter than Path Tracing, or than the more accurate Flicker Free. Usually the difference is not very significant, but something about the scene here means that it is quite a difference - but it's the "Still Frame" version that is "incorrect" by virtue of being simpler and less accurate.

[Giulia91]

thank you very much !!