Changing Dektol concentration

[gedra]

I recently switched from a condenser to dichro enlarger and cannot get the same snappy contrast in prints regardless of filtration number. I know that I need to develop the negatives a bit longer with the new machine, but wonder if changing Dektol concentration from 1:2 to 1:1 will help with my older negatives. Thanks.

 

[mikebarger]

Easy way to find out. Please report back after your test.

 

[Mike Wilde]

Leaving prints in Dektol, lower concentration (I think- from memory here and I might have it backwards, and it was a while ago but at least 1:3) for longer periods can raise print contrast. The down side to this technique is to wait 4' for each print, or get a tray warmer and run the bath at something around 24C for 2:30.

Longer development lets subtle greys come to life that don't surface as quickly. The other option is to add pottasium bromide, which slows down development, and will need more exposure as well, but does increase print contrast.

 

[Ian Grant]

Other way around Mike, you increase the concentration for more contrast and dilute for softer.

So Kodak recommend 1+1 for D72/Dektol for increased contrast, and in practice it does help. It's the same with other print developers as well.

Ian