**Colour Manipulation**

### GRAIN

**Grain Problems when Colour Correcting**www.fxguide.com thread (cache)

You can Colour correct everything, to some degree but then it gets apparent and difficult to manage.

First off what would be great if you got your 2K footage in Log full 10 or 12 bit scanned. That will give you extra space to work with.

Then maybe try and do grain removal First on just blue channel (usually the most grainy) and try with that or on all of the channels and then CC.

Do all of the corrections while in 16 or 32 bit mode so you get most out of fusions algorithms.

Try masking areas of interest and do colour corrections in areas and then combine them together so you are not working on whole picture at one time.

by

**kristijan**(2002)

### Printer lights, F-stops & Points

Fusion Pigsfly Email List (cache)

Light trim is similar to "printer lights", " printer points" or "transfer points" in a film lab.

According to Kodak: One stop is equal to about 7 printer points or 7 transfer points or 7 trims.

- But it is generally accepted that there are 8 points to a Fstop in the UK but only 6 points in the US

I did a few tests and this is what i came up with:

How to check what a point is, in log space(every house has a slightly different log/lin curve) using a mult/brightness node:

How to check what a point is in linear space using a mult/brightness node:

So roughly 1 stop for 7 trims

by

From MathewK on Davinci

There are 8 points to a Fstop in the UK but only 6 points in the US

In Fusion(in log) the Brightness of a UK point = 0.012 / US point = 0.015

Light trim is similar to "printer lights", " printer points" or "transfer points" in a film lab.

According to Kodak: One stop is equal to about 7 printer points or 7 transfer points or 7 trims.

- But it is generally accepted that there are 8 points to a Fstop in the UK but only 6 points in the US

I did a few tests and this is what i came up with:

How to check what a point is, in log space(every house has a slightly different log/lin curve) using a mult/brightness node:

- using a BG colour of value '1'. add a Cineon Log tool set to "lin to log. add a mult/brightness and add another Cineon log set to"log to lin".
- Tweak mult till output value is 0.5 (which is half the value of the original). Which will give you one stop.
- Have several mults together (cloned) 6 or 8 depending if your DOP is EU or US and tweak mult till output value is 0.5
- The result should be about: mult(log):
- lighter: UK point= 1.031 / US point = 1.021
- darker: UK point= 0.992 / US point = 0.976

- The aprox result expressed as exposure (i.e. '+1' exposure is a mult of '2' and '-1'exposure is a mult of 0.5)
- darker: UK point = -0.026 / US point = -0.034
- lighter: UK point = 0.026 / US point = 0.034

How to check what a point is in linear space using a mult/brightness node:

- same method as above
- The result is about: mult(lin):
- darker: UK point = 0.917 / US point = 0.891
- lighter: UK point = 1.091 / US point = 1.123

- The aprox result expressed as exposure (i.e. '+1' exposure is a mult of '2' and '-1'exposure is a mult of 0.5)
- darker: UK point = -0.125 / US point = -0.166
- lighter: UK point = 0.125 / US point = 0.166

**Rafal Kaniewski**(2006)So roughly 1 stop for 7 trims

by

**dfx**(2005)From MathewK on Davinci

There are 8 points to a Fstop in the UK but only 6 points in the US

In Fusion(in log) the Brightness of a UK point = 0.012 / US point = 0.015