BTC Mini-Integrator 2 - Darkroom Exposure Timer

Circa Late 1970's to Late 1980's (ESTIMATED)

A specialized photographic darkroom timer used to precisely control the exposure time of a photographic enlarger. Unlike a standard countdown timer, this unit is designed to measure and compensate for fluctuations in the enlarger's light intensity, ensuring consistent print results.

Use Cases:

• Photographic Enlarger Control: Its primary role is to serve as a precision switch for a photo enlarger. Technicians set a specific exposure time on the mechanical counter to ensure consistent light delivery when printing photographs from negatives.

• Exposure Compensation (Integration): Unlike a basic timer, its "integration" feature allows it to work with a light-sensitive probe placed on the enlarger's baseboard. The device "integrates" the total light intensity over time, automatically shortening or lengthening the exposure to compensate for factors like lamp aging or voltage fluctuations.

• Precision Darkroom Work: The 3-digit counter allows for adjustments in 1/10th of a second increments, making it suitable for complex darkroom techniques like dodging and burning, where exact, repeatable timing is essential.

• Manual Focusing: The Manual mode allows the enlarger lamp to stay on indefinitely, which is necessary for framing the image and focusing the grain before starting the timed exposure.

Key Functions:

• Enlarger Exposure Control: It connects between a power source and a photographic enlarger. When the "Expose" button is pressed, it switches the enlarger lamp on for a duration set by the numerical dial.

• Precision Timing: The three-digit mechanical counter allows for time settings in increments as fine as 1/10th of a second, which is critical for high-quality black-and-white and color printing.

• Integration Feature: The "Integrate" toggle suggests it can work with a light sensor (probe) to automatically adjust the exposure time if the light source's brightness changes (e.g., due to voltage fluctuations).

• Manual/Auto Modes:

• Manual: Allows the user to turn the enlarger lamp on indefinitely for tasks like grain focusing or framing.

• Auto: Uses the set time on the counter for the actual print exposure.

• Cancel: Provides a way to immediately stop an exposure if an error is made during the process.

(H-14.5cm x W-9cm x D-12cm)