The View Camera Store

Getting the Best Results with BTZS Tubes

1. In total darkness remove the exposed film from the holder. Cup the sheet in your hand, with the emulsion inside the curl, and slip the sheet into the tube, being careful not to scrape the film back on the tube lip as you insert it.

2. In total darkness push the film sheet into the tube until the upper edge of the sheet is about 1/8 – 1/4 inch below the tube lip. Screw the tube cap on firmly. If you plan to develop two or more films for different lengths of time, write the individual times on bits of masking tape with a waterproof marker and stick them on the appropriate tubes.

3. Fill the “tube rack” with tempered water (at whatever temperature you prefer to use for development) and float the loaded tubes in it while you prepare the developer. Place a set of extra tube caps in the receptacles in the tube rack so that they can be tempered, too. Spin the tubes occasionally and check the water temperature to be sure it remains constant. If the room temperature is more than a few degrees higher or lower than your chosen development temperature, let the tubes float with occasional agitation for at least 5 minutes to be sure they’re properly cooled or warmed before you begin developing.

4. While the tubes are tempering in the waterbath, prepare the developer, stop bath, and fixer. Be sure the developer dilution is correct and bring the solution to your chosen temperature. Pour 60 milliliters of the developer working solution into each of the extra tube caps and return them to their tray receptacles. Fill an 8x10 or 11x14 tray to a depth of about an inch with normal-strength acid stop bath solution (1 to 2 ounces of 28% acetic acid stock solution per quart of water) at your chosen development temperature. Place this stop tray conveniently close to the waterbath and near the sink drain (or a waste receptacle). Fill a similar tray to a depth of ½ inch or so with film-strength fixer, also at or near the development temperature. Check the waterbath temperature and adjust it if necessary.

5. Turn off all lights. Remove one tube from the waterbath and, holding it vertically with the cap end down to prevent water from entering the tube when you open it remove the empty cap and set it aside. Carefully locate the filled caps in the tray rack receptacles, and screw the tube into one of them, leaving the tube standing in the receptacle. Repeat this operation for each of the remaining tubes.

6. Turn on the lights. If your films require different development times, set your timer for the longest time, then mark the shorter times on the timer dial with bits of tape. Remember that these intervals will be SUBTRACTED from the longest time and not added from zero. For example: if you have times of 10:00, 8:00, and 5:30, set the timer for 10 minutes, then mark the dial at 4:30 (10:00 minus 5:30) and 2:00 (10:00 minus 8:00). When you’re ready to begin, remove the tubes from the rack receptacles, keeping them vertical so that the developer in the caps will not run up onto the films, and tighten each cap firmly. Arrange the tubes into a group that you can grasp easily; start the timer going; pick up the tubes, and immediately shake them vigorously in a more or less horizontal position so that the films will be instantaneously and uniformly wet with developer.

7. After a few seconds of this shaking, drop the tubes into the waterbath and begin the “log rolling” agitation that you’ll continue throughout the development period. This doesn’t have to be frantic, but you should be sure that ALL of the tubes are rotating ALL of the time. Pay attention to this, and check (and adjust) the waterbath temperature frequently; agitation, time and temperature are your major development controls and carelessness with any of them is likely to affect your results adversely.

8. Working in dim room light (or safelight), about 10 seconds before the first development time will expire, pick up one of the tubes and, holding it vertically, loosen the cap a little while you watch the clock. As the time expires, quickly remove the cap and...

9. Plunge the open tube into the stop bath tray, rotating it there several times to wet the entire film immediately.

10. Then dump the developer out of the cap into the sink or the waste receptacle, and return to the tray rack to continue agitating the remaining film tubes. You can let the tubes accumulate in the stop tray, agitating them occasionally, until all the films have been developed. If you can open a tube and get it into the stop bath within 2 or 3 seconds there is no danger of fogging the film perceptibly if the room illumination is dim and indirect.

11. After the films have been treated in the stop bath for at least 15 or 20 seconds (they can stay in the stop until all the films have been developed, if you like) you can remove the films from the tubes and fix them in the open tray in dim room light. Removing the sheets is not difficult if done correctly: the trick is to grab a corner of the film and twist a little to “tighten” the curl and pull it away from the tube walls, after which it should slip out quite easily. Because the films press quite firmly against the inside of the tube the developer can’t reach all areas of the film back so the anti-halation dye backing cannot be entirely removed. You’ll see this residual dye as a blotchy dark pattern on the back of the film sheets as you extract them from the tube.

12. Place the film sheets in the fixer tray and shuffle them gently (removing the bottom sheet to the top, repeatedly) and frequently until they’re thoroughly fixed. Be careful to avoid scratching the films during this operation; adding a little hardener to the fixer will help to avoid damage. Films other than Kodak films should be fixed at least twice as long as it takes them to clear. All tube-developed Kodak films should be fixed for at least 4 times as long as it takes them to clear because their backing dye is unusually difficult to eradicate (although it will APPEAR to be cleared rather quickly). The TMax films should be fixed until their characteristic magenta (sensitizing) dye is lightened considerably and changed to a light tan color. Kodak films will generally require an extended treatment in double-strength hypoclearing bath to remove the last traces of that tenacious anti-halation dye. Even though there may be no visible sign of it in the fixer or clearing bath, it may reappear as a cyan stain after a few minutes in the wash water. If this occurs, return the films to the clearing bath for another 5 minutes or so. Check for this faint cyan color in the wetting bath, too; for some reason the wetting agent sometimes seems to bring out the stain even if there was no sign of it in the wash bath. Aside from this extra precaution, you can wash and dry the films in your usual manner. Films by other manufacturers don’t seem to need this extended clearing treatment (although it probably won’t hurt them), and can be fixed, washed, and dried conventionally.