Exponential Color Mapping, Now and Then

[RErender]

I have some old scenes (1.47) that I would like to render in 1.50.

Problem is that the output with exponential @ 2.9,2.8 is very different between versions. The 1.50 version is darker overall. Setting Gamma to 2.2 in the color mapping settings brings the overall brightness to about the same level but contrast is greatly reduced.

Is there an adjustment I can make to get the color mapping to work like it used to?

Thanks!

[RErender]

Ok, so multiplying the values by 2.2 produces the desired result.

[RErender]

Well, close but not exactly...

[vlado]

The exponential color mapping is the same between versions, but maybe you could try to figure what is causing the different brightness in the first place (light settings or something else).

Best regards,
Vlado

[RErender]

the 2.2 multiplier is too close to be ignored ?

Really looks like a gamma shift, though like I said changing the gamma produces the right brightness but with reduced contrast.

I'll take a look at the lights when I get to work, the scene is mostly lit by area dome light + one direct light. Just a plain color on the dome light. GI is imap/lc i've tried both the legacy and the new samplers.

Any ideas what else to check? Nothing has changed in the color mapping since the addition of the gamma spinner?

[voltron7]

have you tried the "use max's photometric scale" tick box?

[RErender]

have you tried the "use max's photometric scale" tick box?

yes, tried it, turned the scene black.

[vlado]

Looks the same when I try it here; I only had to turn on the "Subpixel mapping" option to get a complete match between the two versions (and change the DMC noise threshold, of course). This is with exponential color mapping at 2.9 and 2.8 bright/dark multiplier respectively, dome light and one direct light (no GI):




Best regards,
Vlado

[RErender]

hmm, weird, I'll keep looking into to it.

Thanks for giving it a go.

[RErender]

Ok, so it does look like a light value issue. Seems a dome light with a 1.49 value of 7 W now = a 1.50.00 value of 11.2 ish W (radiant power). Has the "size" of the dome light changed? Switching to full sphere seems to result in similar power output at 7W but of course the rays from below the horizon change the render significantly. This seem right? Is there a factor to adjust old dome light intensities?

[RErender]

Switching 1.50.00 to "Default (image) with a multiplier of 7 is very close but still slightly different. I can probably live with this result but it would be ideal if I could match the output exactly.

[themaxxer]

did you change the AA settings? because the adaptive qmc produces darker images with more subdivs... I know you could compare it with the subpixelmapping. but there's a difference between the AA methods. or it could be the primary bounce settings. did you change it from IR to QMC? there's also a difference in brightness.

best regards
themaxxer

[RErender]

Except for the version change from QMC to DMC everything else is the same, perhaps this is where the difference lies. If so we can live with the difference.