A confusing problem with lens f stops and timer f stops

[Kino]

You can place an ever so tiny amount of Carbon Conductive Grease on the pins of the enlarger lamp (only the tips of the metal) and this will help prolong the lamp and the lamp socket by inhibiting oxidization of the contacts and the subsequent pitting of the surfaces.

The smallest tube you can buy would last about a dozen people a lifetime, if only used for this purpose.

 

[MattKing]

You can place an ever so tiny amount of Carbon Conductive Grease on the pins of the enlarger lamp (only the tips of the metal) and this will help prolong the lamp and the lamp socket by inhibiting oxidization of the contacts and the subsequent pitting of the surfaces.

The smallest tube you can buy would last about a dozen people a lifetime, if only used for this purpose.

Sounds like a great idea for a group purchase for my Darkroom Group

 

[Sergey Ko]

1. The DENSITY is the result of exposure + development. The paper always need development "to the end". You must provide the same correct development for the tests.
2. The is also the rule of reciprocity failure (reciprocity law failure, or the Schwarzschild effect.