Re: Gum calibration (was: Paper negatives- Ink Selection)

[Alberto Novo <alt.list@albertonovo.it>]

> do not forget that if you vary the distance the  
> exposure times are increasing 'square' (Is it the correct word for:  
> distance two times, exposure times 4 times ?) .
For a diffuse source (like a bank of tubes) and at short distance, exposure 
varies with a linear law. Distance two times, exposure two times. 
Alberto