Linear mapping and burnouts

[Karrde]

Hi guys,

 

I know that the LWF was discussed over and over again, but belive me, I tried to search for an anwser up to no avail.

 

I have been using the semi-LWF workflow for my interiors with Reinhard colour mappping and it of course does the job, but I wanted to try the "true" LWF, especially for better control in post. So I ticked the "dont affect colors", changed to linear mapping, and of course ticked the sRGB button in VFB. No rocket science here.

The problem is, my lights (both windows and interior fixtures) are blown out like hell. Yes, i can compensate with camera exposure, but then whole interior is just dark.

 

I am a bit clueless here, although the anwser is probably simple. Anyone could help me with it? I saw some discussion over this at... i think it was Bertrand's Benoit blog (might be wrong, it was a long time ago and i can't find it now) but no anwser was given.

[Corey Beaulieu]

The way that I have always understood the differences in these methods is this:

 

Reinhard boosts the saturation of colors as they burn out so that they do not actually burn out and Linear just lets them burn. That much I think we know. The reasoning behind all of this is that the Reinhardt method simulates the way the human eye works and Linear simulate the way a photographic camera works. In the end, both tend towards the realistic because we see imagery from a camera often and we see through our own eyes constantly.

 

The difference comes in how you would like to manage things in post. With Reinhardt you will tend towards painting in the burns and toning down some of the the saturation and with linear you will tend towards adding in contrast and toning down bright areas.

 

You may find it helpful to use the brightness and darkness multipliers with Linear workflow.

[Ernest Burden III]

If you want to leave it to post, render to 32 bit. Otherwise, color mapping is your friend. Reinhard is a blend of two other methods (exponential and something), so you can play with the burn value to have more of one or the other.

[Scott Schroeder]

If you take it to post with the linear mode, would you want to light your scene to medium values then control the brights/darks in post (on separate layers of course)? So your render would look pretty neutral or evenly lit coming out of max, then the good stuff comes later.

[Nic H]

presumably you are going to be applying an srgb colorspace to it somewhere anyway

i think you are over complicating things to be honest...

 

i don't see the real purpose of a 'pure linear' setup for arch vis - especially if you arent working with footage.

 

there is a lot of misinformation around.

[Stephen Thomas]

Your lights will be blown. The whole point of using a linear format is that you are storing values greater than 1.0, i.e. pure white. What brings things back into line is tone mapping. Either done through the colour mapping settings via exponential or rheinhard and saved as 8-bit or saved linearly to 32-bit format then tone mapped in post production software using curves and levels adjustments. Both are valid, the second one however gives you the added control of adjusting later without re-rendering.

[Crazy Homeless Guy]

K.I.S.S.

 

(Keep It Simple Stupid) http://en.wikipedia.org/wiki/KISS_principle