I have been using a besler digital timer that only goes up to 10 seconds as the x10 function gives erratic times so it is unusable. I like this timer as it has a foot switch and metronome function so I use it anyway. Small enlargements can usually be done in less than 10 seconds but 11x14 from 35mm can take multiple 10 seconds exposures plus whatever burning time. As I have gotten used to this odd system I find that I NEVER change the timer and always use muliples of 10 seconds. For less than 10 seconds I use the metronome and a dodging card to completly block the unneeded time. I have learned to like this system better than changing timer settings and it occurs to me that many others may actually do the same. I think I read the saint Ansel did something similar. But--- Am I missing something in that 3x10 seconds does not add up to 30 seconds continuous time? I have been assuming that any error is absorbed by my personal system as long as I am consistent. Right?? If anyone knows how to fix a besler I wouldn't mind having a workable unit even if I won't use it.