Predictable Printing! This timer uses the straightforward and logical “constant density” method of timing, otherwise known as “the f-stop method”. It’s the same system you’ll find in your camera. When applied to printing it results in smooth and consistent exposure changes with predictable results on the paper. It makes judging exposure much simpler and makes burning in a breeze.Condition:This unit is \"like new\" having been carefully used by a non-smoker in a darkroom with a wet side and a dry side: the timer has never been exposed to moisture or chemicals. Items included in this sale:

• StopClock Professional Timer
  
• 6 ft. power cord (US style 3-prong U-ground 115/120 VAC)
• 12 in. adapter from male EIC to female NEMA (US 3-prong) for enlarger hook-up
• 6 ft. cord for safelight hook-up.
• Instruction Manual
• 4 Spare 5 Amp fuses (You will probably never need them but you will be prepared).
  
• Custom made wall plate to control hard-wired safelight outlet(s) either manually or automatically by the StopClock Timer. If fits a standard 2 gang junction box, and a wiring diagram is included. (Installation and use of this item is optional)
  

StopClock Professional Features:

• Base exposure time 1.0 seconds to 240 seconds, in steps of 1/24th to 1/2 f-stop (or of 0.1 or 1.0 seconds in linear time mode). Time is controlled to 0.01 seconds.
• All exposure times are set in coarse and fine steps of actual exposure rather than simple seconds, producing consistent changes on the paper. The fine step size is 1/24th f-stop (approx 2%). The coarse step size can be set to 1/2, 1/3, 1/4, 1/6 or 1/12 of a f-stop. Coarse/fine button toggles between 1/24th and the set coarse time step.
• Nine subsequent exposure times can be programmed, each calculated either relative to the base exposure or the total exposure time thus far. Burn-in exposures are set in steps of 1/12th to 1/2 f-stop. If the base exposure is changed, the burn-in exposures are recalculated to maintain the density relationships.
• Two completely independent channels, each having separate base and burn-in exposure times.
• Split-grade mode, in which exposure can be controlled using one channel while the second can be used to adjust contrast. Equivalent contrast is displayed in steps of 0.1 grade.
• Automatic test strip mode, for quickly producing test strips with 1/12th to 1/2 stop increments either as an incremental exposures or separate complete exposures.
• Exposure Compensation of +/-20% to allow for dry-down or and/or toning with respect to a test print.
• The clear yellow LED display brightness can be set to one of three levels. The display color has been chosen to be safe for both color and black and white printing.
• Audible beep at the end of each exposure, and optional seconds tick whilst the enlarger is switched on.
• Rugged steel enclosure and high quality components for reliability. Illuminated control buttons.
• Automatic safelight switching; manual (focus) mode; 500 watts switching capacity; comes complete with a foot switch for hands-free operation.
• Exceptionally easy to use! All timing, including switching between channels, can be controlled from the foot switch.

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