log Lin setups

[Shervin Shoghian]

hello.

Just wanted to see what you guys recommend for the Log Lin convertion. Is it best to leave it at the default 1.7 when working with 10-bit Cineons in Shake? I’ve also heard of using 0.45 when working with 2.2 Gamma Monitors. any info on this would be great. thanks !!!

swerve.

[wpiggy]

Usually i use VLUT instead of loglin conversion. In VLUT i set both gamma settings to 1. This produce non-contrast image, like on intermediate film. Default settings make picture more contrast, closer to print film.

[Dr_P]

There are quite a few different processes going on here that need to be separated out to make more sense of what values to use:

neg gamma: this relates to the slope of the straightline portion of the neg stock’s characteristic curve. Shake default values of 0.6 seem a little high, something along the lines of 0.5 – 0.55 might be a little better, but this depends on the neg stock.

disp gamma: this relates to the gamma applied by the gfx hardware on the way out to the monitor. On SGI boxes this used to 1.7, on PC boxes this is 1.0, macs have something else still. In any case you should probably leave this at 1.7 and let shake worry about what platform it is running on as the NR people have done this for you and the 1.7 is there for historical reason dating back to the Cineon times.
So in actual fact you should be pretty good with the default settings.

What you may well want to do is to apply a viewr lut, this should be a simple gamma node with a value of 2.2. This will compensate for the monitors native gamma value which is around that for most monitors. This will enable you to view linear images without any print film specifics.

Hope this helps

swerve wrote:

hello.

Just wanted to see what you guys recommend for the Log Lin convertion. Is it best to leave it at the default 1.7 when working with 10-bit Cineons in Shake? I’ve also heard of using 0.45 when working with 2.2 Gamma Monitors. any info on this would be great. thanks !!!

swerve.

[Author]

Posts