The Multi-Print Efficiency: Mastering Part Enlargement Easels

In a traditional darkroom, paper is often the most significant recurring expense. While a standard bladed easel is perfect for a single masterpiece, part enlargement easels—such as the legendary Durst Comask and the Jobo Varioformat—unlock a different level of utility. These specialized tools are designed with a series of light-tight hinged flaps or sliding masks that allow you to expose specific quadrants of a single sheet of paper while keeping the rest in total darkness. Whether you are creating a "package print" of four 4x5 images on one 8x10 sheet or performing a high-precision series of exposure tests, these easels are the secret to economic and consistent darkroom throughput.

Purpose

The primary goals of using a part enlargement easel include:

Economic Efficiency: Printing four 4x5 prints on a single 8x10 sheet reduces chemical and paper waste.
Comparative Analysis: Seeing four different negatives (or four different exposures of the same negative) side-by-side on the same physical paper for easier comparison.
Contact Sheet Alternatives: Creating high-quality "enlarged contact prints" of your best frames without wasting a full sheet for every individual shot.

The Logic: Light-Tight Sectioning

The engineering of these easels relies on a "sandwich" design. You place the paper in the base, and a top frame with multiple hinged doors (Varioformat) or a rotating/sliding mask (Comask) sits flush against the emulsion.

The key feature is the Focusing Surface. Most models, like the Jobo Varioformat, feature a white surface on the back of the flaps or a separate focusing panel. This surface is at the exact same height as the paper underneath, allowing you to focus and compose the image with the enlarger light on without fogging the paper hidden beneath the other flaps.

Step-by-Step: Printing a 4-in-1 Sheet

1. Setup and Alignment

Place the easel on your enlarger baseboard. Before loading paper, open one flap and project your image. Adjust the enlarger height and focus so the image fits perfectly within that specific quadrant's opening.

2. Loading in the Dark

Under safelight conditions, open the main frame of the easel and slide a fresh sheet of 8x10 paper into the guides. Close the frame and ensure all four flaps (or the mask) are securely shut.

3. First Exposure

Open only Flap 1. Perform your exposure (e.g., 10 seconds at f/8). Once finished, close Flap 1 immediately. The paper is now light-tight again.

4. Sequential Exposures

Switch your negative or adjust your composition. Use the white surface of Flap 2 to re-focus if necessary. Open Flap 2 and repeat the process. Continue until all four quadrants are exposed.

Tip: Keep a small notebook to track which negative is in which quadrant to avoid confusion during development!

Use Case: The Visual Exposure Matrix

A photographer is unsure of the perfect contrast grade for a difficult negative. Instead of using four separate test strips that are hard to keep track of, they use a Varioformat easel.

The Action: They expose the same negative four times on one sheet. Quadrant A gets Grade 2 filter, Quadrant B gets Grade 3, Quadrant C gets Grade 4, and Quadrant D gets Grade 5.
The Result: After processing, they have a single 8x10 sheet showing the exact effect of every contrast grade on the full composition, making the final decision much clearer than small strips would allow.

Best Results

Technique	Benefit	Caution
Black Underside	Prevents back-reflection through paper.	Make sure the easel base isn't reflective white.
Weighted Flaps	Ensures a crisp, sharp border.	Dust the hinges often; debris can cause light leaks.
Tape-Down Base	Prevents the easel from shifting.	If the easel moves between flaps, your margins will be uneven.

FAQ

Can I use these for color printing (RA-4)?

Yes, but with extreme caution. Color paper is much more sensitive than B&W paper. Even a tiny light leak between the flaps during a long exposure will cause color fogging on the adjacent quadrants. Ensure the flaps are completely flush.

How do I remove the paper without touching the emulsion?

Most Varioformat easels have a small lever or a "finger cutout" at the corner. Pressing this tilts the paper up, allowing you to grab it by the edges without leaving fingerprints in the center of your four images.

What if my image is vertical but the flap is horizontal?

You will need to rotate the entire easel 90 degrees on the enlarger baseboard. This is why taping down the base is only recommended after you have composed all four shots if they require different orientations.

Disclaimer

Part enlargement easels like the Durst Comask are precision instruments. If the hinges become bent or the sliding masks are forced, they may no longer be light-tight. Always perform a "dry run" with a scrap piece of paper if using a second-hand easel for the first time. March 2026.

Tags: Darkroom_Equipment, Analog_Printing, Durst_Comask, Jobo_Varioformat