Lazy_Tonemap v1.0

This is a nuke gizmo that i've found useful when your comp ends up too bright and shoots values over 1.0. Sometimes it can be little bit tedious to affect only those really high values, and ignore the low values. This is when tone mapping can be useful.. This gizmo doesn't use the actual RGB values, but the luminosity of the pixel, and therefore maintaining saturation.

Key value is something that i devised there based on some paper (sorry! cant remember who wrote it originally), but it rarely produces anything sensible :) it has a tendency to boost contrast. Can get some kind of results by using gain/gamma knobs..

What i've found useful is the white point tonemap, which i've put as the default. It is useful where your dynamic range shoots over 1 and you want to retain some of that information. The bigger the value is from 1, the higher whitepoint it tries to maintain. What this one does is that it returns values over 1.0 (in luminosity colorspace) back to 1.0.

Knobs:

The first one is to choose the different methods. White Point being the most useful.

White point is the threshold to be tonemapped, the higher the flatter your image gets. 1=original image, values below that dont make sense.Play around with really high values to get a feeling of it. It depends completely from one image to another.

Key value is for the key value thingie, wants low values.

Gain and gamma are self-explanatory and  mainly just for tweaking and testing. I always use a colorcorrect/grade node before to create the same result. They just affect a grade node before the tone mapping.

Simple mode just brutally moves the whole dynamic range down to meet 1.0.

PS. Where i've found most use is rendered footage where values go accidentally too high. Fluid dynamics renders like explosions and fire can be tricky to tone down sometimes. It can be useful to tone down a complicated comp that ended up too bright. The nice thing is that if the information is there in high dynamic range, and you can get it back if you use really high values.

PPS. Since its a gizmo that uses nuke expressions, it should work on all platforms and versions over 6. It should be pretty standard stuff..