The Use of Polaroid 55 Positive/Negative Film
With the Polaroid
MP-3 Land Camera
(Taken from directions developed by the
CMRAE Laboratory
at MIT by Prof. H. Lechtman)
Polaroid 55 Positive/Negative Film is a fine-grained, panchromatic film of medium contrast that delivers both a positive print and a negative in 4 X 5 inch format. This film is easily adapted to the Polaroid MP-3 Land Camera system in the darkroom. The following protocol describes the use of Polaroid 55 P/N film with the MP-3 camera.
1)
Prepare the necessary materials:
a. Film packets (Dr. Reber’s office)
b. Print-coating brushes (with film)
c. Polaroid 545 Land Film Holder (Dr. Reber’s office)
d. One plastic tray filled with sodium sulfite solution (under the sink in the darkroom)
e. One plastic tray filled with hypo flo wetting agent (under the sink in the darkroom)
f. One plastic tray for washing in running water (next to sink in the darkroom)
g. Clips for drying
All of these materials are available in the archaeology labs. Dr. Reber will prepare all chemical solutions used in processing the negatives, and each student will be trained in proper handling procedures.
2) Compose the photograph on the MP-3 camera as described in the handout “Photomacrography with the Polaroid MP-3.” A copy of the MP-3 protocol is posted next to the camera.
3) Load the film onto the film holder. Before being mounted on the camera, a film packet must be loaded onto the Polaroid 545 Land Film Holder, which is located next to the film in Dr. Reber’s office. The film holder can hold only one film exposure at a time—one film packet. To load a film packet:
a. Move the control arm to “L.” (the arm is left at “P” while the holder is not in use.)
b. Orient the packet with the metal cap end to the left and the flaps on the right so that the word “Polaroid” is right-side-up and facing you. Be very careful not to touch the negative pod area, which is clearly marked with warning symbols. With one or both hands (if extra leverage is desired) hold the packet about the middle area (left of the pod) and insert it into the film holder. Once it is inserted about halfway, hold the flap end of the packet and push it in until it stops. Make sure the packet is in as far as it will go, but also be careful not to buckle the packet.
4) Insert the film holder into the MP-3 ground glass screen frame. The film holder is placed onto the MP-3 in the same way we demonstrated in lab the other week. Lift the right side of the ground glass screen frame and slide the film holder in place underneath it. Push the film holder as far as it will go and check to see that the arm in the left rear of the ground glass screen is displaced, extending to the left of the ground glass.
5) Expose the negative. Before exposing the negative, make certain that the interlock disabling switch (on the shutter trigger) is off. You may check this by testing the shutter release before exposing the negative. To reveal the negative, withdraw the packet by holding the flap firmly and pulling it until it stops. Check to see that the pod area is flat and smooth by running your thumb and forefinger lightly over it. If it is not, you have withdrawn the negative along with the envelope. Push the envelope in again, and withdraw it once more, checking the pod.
6) Take the picture. The negative is now in place and you are ready to take the picture. Click the shutter release. As soon as the picture is taken, push the envelope back into the ground glass frame and remove the film holder altogether. Forgetting to replace the envelope will result in a ruined negative. Move the control arm to “P” (process). From the flap end, pull out the film packet with a firm, unhesitating motion.
7) Time the print development. As with other Polaroid films, the positive print develops immediately and its development must be timed. As soon as the packet is removed from the film holder, begin timing the processing. The temperature of the film holder at the time of processing exerts an important influence on the processing time required. At room temperature (70 degrees F) or greater, the processing time is 20 seconds. Please consult Dr. Reber in cases of lower film/film holder temperature, as the processing time must be adjusted accordingly. After the recommended processing time (probably 20 seconds) separate the print from the negative by grasping the two flaps opposite the cap end and quickly pulling the packet apart all the way to the cap end.
8) Pull the print away from the envelope backing. The print and its mask will separate completely from the negative section and cap. Remove the mask from the print and discard.
9) Coat the print. Place the print on a clean surface (use craft or plain white paper) and coat it immediately, using the coating roller provided with the film. Six to eight overlapping strokes are recommended to cover the entire print, including the borders. Each coater will cover no more than five prints; do not attempt to stretch the use life of a coater, because the results are streaky and poor. Allow the print to air dry for several minutes before handling. The coat tube MUST be capped between uses.
10) Separate the negative from the envelope and the cap. Never touch the damp face of the negative. Flex the perforation at the metal cap end of the negative. Holding the cap in the right hand and the tab in the left, tear the negative along the perforation. Do this with extreme care!! If your tear does not remain on the perforation, the negative will be torn and thus ruined!! The opposite tab remains in place.
11) Clear the negative in sodium sulfite solution. Go immediately to the sodium sulfite solution tray. Insert the negative GENTLY into the tray, using a pair of tongs held at the EDGE of the negative. If you hold the negative in the middle with the tongs, you will scratch the negative! Gently agitate the tray by moving the tray up and down for about one minute as the dye clears and the developer drops off (a layer of dark purple/black developer still adhering to the negative normally sloughs off during immersion in sodium sulfite). Sodium sulfite clears the negative so that it will not be stined or marked by the residual chemical activity of the developer. Note: solution should be at room temperature, 65-75 F.
12) Wash the negative. Remove the remaining tab from the negative, flexing along the perforation and tearing carefully away. Wash the negative for around five minutes in running water at about 70 F.
13) Dip the negative in wetting agent. After washing, dip the negative briefly in Kodak Photo-Flo wetting agent, and drain for a few seconds.
14) Dry the negative. Hang the negative to dry by clipping it to the wire hanging above your head. Be sure to clip the negative at the EDGE rather than in the middle of the negative.
15) Store the negative. Once a negative is dry, place it in a protective wallet. These are kept in the top drawer of the desk with the MP-3 camera on top of it. Record information concerning the object and the photographic conditions on the envelope before inserting the negative. Include with your information
a. What the object is, including site name and number, FS number, square and level/feature information.
b. The f:stop and shutter speed
c. Camera position when the picture was taken
d. Whether there are other photographs of this object
This information ensures that the photograph can be retaken in case of disaster, and that we are not awash with photos of unidentified objects after this class is over.