Author Topic: strong banding when saving  (Read 1473 times)

2021-11-20, 12:06:25

muoto

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Hello,

i have very strong banding effects on subtle coronasky gradients when i save as JPG (or tiff 8bit) which are not at all visible in the VFB.

i tried with or without luts, its the same.

when i save as 32bit exr, and then convert in PS, it's OK.

Any ideas ?

Thanks

(max2022 cororna 7 latest release)

ps: attached screenshot, left is the saved jpg, right the VFB (some obvious small jpg compression also while posting, but still... and strangely the color is a little off as well !
« Last Edit: 2021-11-20, 13:09:52 by muoto »

2021-11-21, 17:55:25
Reply #1

TomG

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Probably due to the way the host software (Max) is converting the image down to 8 bits on saving (the save routines are not part of Corona, but part of the host software). Could try a format like PNG, or could stay with your current method of saving with a full bit depth and letting some other software do that conversion step.
Tom Grimes | chaos-corona.com
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2021-11-23, 11:52:35
Reply #2

muoto

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isn't that problematic that what you see in the vfb isn't saved correctly ? Anyway, even if the data in the vfb is linear, the image is still 8bit on your screen, no ?

2023-02-17, 11:36:29
Reply #3

maru

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As Tom explained, this is related to the subtle differences between what we display in the VFB and what is displayed in other software (gamma 2.2 vs sRGB gamma). This may be fixable in the future, but is independent from us.
Also, it depends on the monitor - I can see strong banding in the left and right example.
Marcin Miodek | chaos-corona.com
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