Film Developing: Process User Guide

To make the best use of the wonderful printmaking processes at the Special Edition, we have put together our Special Edition Process User Guide. This film processing section of the user guide will get you aquainted with our developing process and chemistry used. To get real a copy of the full Special Edition Process User Guide, come on by and visit!


November 2018 Update: Our in-house Photographic Processes User Guide and Paper Survey have made it public! Download the guide and survey as your practical working reference to historical alternative processes!


1. Introduction
Special Edition Art Project (SEAP) is a public photographic print manufacturing facility available to the community for workshops and on a rental basis. The SEAP team is available to provide consulting services on the various photographic imaging and darkroom processes available within the space. SEAP uses manual photographic tray processing as the print development process flow, supporting classic B&W sliver gelatin print making as well as several historic processes wedded with modern chemistries, all with ecological wisdom.

We have chosen eco-friendly processes and processing chemistries for use in our facility – good for you and good for the environment. Our expectation is that you can learn and practice the processes in our facility in an environmentally safe manner and hone your skills in your personal space using the wisdom imparted to keep the world safe, clean, and full of art. The flip side of course is that we are using chemicals, so need to be aware of spilling, touching, drinking. Will be wearing gloves when appropriate. We will be keeping splashing and dripping to a minimum. We will be working wet processes in designated sink areas only. We will not be looking directly into the ultraviolet light sources – these are not tanning stations. Refer to the facility safety guide ‘SEAP Spill Prevention and Response Plan’ for detailed working information.

2. Photographic Processes
The silver halide process - gelatin sized papers sensitized with silver bromide in the early days and silver chlorobromide in the paper’s latest manifestations - muscled out its photosensitive iron based predecessors due to silver halide’s much higher light sensitivity. The higher sensitivity allows for smaller cameras with smaller negatives which in turn requires prints to be created via enlargement onto large sheets of photographic paper. No longer were practitioners tied to contact prints from equal sized negatives or slow exposure times for print making. With marketing at its best, these practitioners then became beholden to the makers of silver gelatin enlargement printing papers. Time marched along and then came high resolution digital cameras and affordable archival/gallery/museum quality color printers.

2.9. B&W Film Development

2.9.1. Overview

Special Edition in-house photographic film and paper processing chemistry used for B&W silver gelatin is made by LegacyPro, called eco•pro. The eco•pro film developer is essentially XTOL, a safe developing agent related to Vitamin-C, made of the same chemistry, same developing schedule, and same reference material as Kodak’s now discontinued XTOL.

2.9.2. Filmomat Film Processor

Per run, the Filmomat sequences through 500ml of chemistry per process step. Each of chemical tanks A, B, and C can be cycled per film process program. Tank B is temperature controlled via water bath so contains the temperature sensitive developer chemistry. Tank C is used for the fixer and tank A for the final water wash. Film development capacity is defined by the film canister itself. The 35mm/120 roll film canister will accept 2x reels at 35mm, or 1x reel at 120. A single reel can hold 2x rolls of 120 or 1x roll of 220 film. The 4x5 sheet film canister will accept 6x film sheets.

2.9.3. Chemistry Preparation

Note: Always check the fixer for exhaustion every 4x rolls of film. Better safe than sorry.

eco•pro Film Developer: Mix 1:1 prepared eco•pro full strength film developer with water to produce desired amount of working strength solution. For example, 250ml full strength developer into 250ml water to produce 500ml of developer working solution. Developer is used one-shot at 500ml per run of the Filmomat processor.

eco•pro Clear Stop Bath: N/A - eco•pro chemistry does not require a chemical stop bath. 3x 30 second water rinses are sufficient to neutralize the developer chemistry.

eco•pro Neutral Fixer: Mix 1:4 eco•pro neutral fixer concentrate with water to produce desired amount of working strength solution. For example, 200ml of liquid fixer concentrate into 800ml water to produce 1L of fixer working solution. Fixer is used until exhausted at 500ml per run of the Filmomat processor. LegacyPro eco•pro neutral fixer is documented to provide archival properties for 25 rolls of 35mm/36 or 120 film, or 100 sheets of 4x5 film per liter of fixer working solution. At this capacity, 1L of eco•pro Neutral Fixer will support the full packaged 5L mix quantity of eco•pro full strength Film Developer mixed 1:1 into working solution to provide for single shot development of 20 rolls of film at 500ml / processing run. Always check the fixer for exhaustion every 4x rolls of film.

eco•pro Hypo Wash: N/A - eco•pro chemistry does not require a clearing agent if fixer is used per prescribed parameters. eco•pro guidance calls for a 4 minute water wash in lieu of a clearing agent when fixer is use to a maximum capacity of 25 rolls per liter or equivalent of working solution.

Kodak Photo Flo 200: A wetting agent used to displace wash water from the film to minimize water spots, drying marks, and speed drying time. Typical mix is 10 drops per 500ml water.

2.9.4. Processing


First and foremost, follow the Filmomat user guide and film canister loading sequence outlined in the Filmomat documentation. Failure to do so will result in poorly developed film and potentially a broken film processor. Nobody wants to be the cause of either.

The B&W Film developing schedule with the Filmomat using eco•pro chemistry is exceptionally robust and accurate. Developer time and temperature should be obtained by referencing the Massive Film Development Chart at DigitalTruth. The eco•pro recommended fix time is between 2 and 5 minutes while the final wash time is recommended at 4 minutes. Opting on the longer side of these to 4 minutes and 5 minutes add archival margin to your film without adding much to the overall developing time.

Once the processing sequence is complete, remove the film spindle & reel from the canister and place it in a separate container containing Photo-Flo for the film’s final wash. Soak the film while still on its reel for one minute to displace the residual wash water with this wetting agent. Remove film from the reel and lightly squeegee the film, w/o damaging the fragile emulsion, hanging the film to dry in a low traffic and dust free area. 

© Special Edition Art Project, LLC 2018