Basic Photography Course

303.41

Figure 10-19.Agitation of a small tank.

fixer into the sink. The fixer can be reused and then later
saved for silver recovery.

11. The film can be washed either in the tank or in

a roll-film washer. When the tank is used, insert a hose
down through the center of the reels until it is about 1/2

inch from the bottom of the tank. Adjust the water (at
the same temperature the film was processed) so a

steady overflow is created. Wash the film for about 20
minutes. When you use a rapid roll-film washer, again,
adjust the water temperature and place the reels
containing the processed film into the washer. Adjust the
rate of water flow until the reels start to turn. When the
reels start to turn, adjust the rate of water flow until the
reels stop turning. Set the timer and wash the film for
about 5 minutes.

12. While the film is washing, rinse the processing

tank, tank cover, and cap with clean water. Fill the tank
with water (check the temperature) and add the wetting
agent. After the film has been washed, place the film,
still on the reels, into the wetting agent solution. Replace
the tank cover and cap and agitate the film in the wetting

solution very S-L-O-W-L-Y for 1 minute.

13. After 1 minute in the wetting solution, remove

the loaded film reels from the tank. (Do not save the
wetting solution.)

14. To dry the film, attach the end of the film to a

film clip in the drying cabinet. Let the film unwind from
the reel as you slowly lower the reel.

When the film is unwound, depress the grip clip (if

the reel has one) or remove the film from the core of the
reel. Squeegee the film and attach a second film clip to
the lower end of the film. Close the drying cabinet door

and dry the film.

Photographer's Data Sheets

Sometimes a photographer's data sheet will

accompany film that enters your imaging facility to be
processed. The photographer's data sheet will provide
you with information on how the film was shot, lighting
conditions, and specific processing instructions. When

a photographer's data sheet accompanies the film or job

order, you should process the materials specified by the

form.

Cleaning Up

10-25

After processing, the darkroom and all equipment

must be cleaned up immediately. Rinse thoroughly all
processing equipment: tanks, reels, hangers,
thermometers, funnels, and so forth, in clean, warm
water. Place the clean equipment where it can dry before
it is needed for the next processing run. Always keep the
processing room shipshape.

REVERSAL PROCESSING

Normal processing of black-and-white film

produces a negative; from this negative, a positive is
made. However, by using the reversal process, you can
produce a positive image directly on the
black-and-white film.

In the reversal process, a negative image is first

obtained by developing the original latent image in a
developer that contains a silver halide solvent. This
developer dissolves some of the excess silver halides.

After leaving the developer, the negative image is

dissolved away in a bleach bath. The silver halides
remaining are chemically "exposed" (fogged) and
developed by a second developer that provides the
positive image.

Not all black-and-white films reverse well. Films

that reverse well are Kodak Direct Positive
Panchromatic Film 5246 (35mm), T-max 100 Direct
Positive Film, and Kodak Technical Pan Films (35mm).
Instructions for reversal processing of these films can
be found in the Photo-Lab-Index.

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Basic Photography Course

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DOFMaster for Windows On-line Depth of Field Calculator DOFMaster for Mobile Devices On-line Depth of Field Table Hyperfocal Distance Chart Articles FAQ Recommended Books Support Contact Links Home As an Amazon Associate I earn from qualifying purchases.	contents <- previous page next page -> 303.41 Figure 10-19.Agitation of a small tank. fixer into the sink. The fixer can be reused and then later saved for silver recovery. 11. The film can be washed either in the tank or in a roll-film washer. When the tank is used, insert a hose down through the center of the reels until it is about 1/2 inch from the bottom of the tank. Adjust the water (at the same temperature the film was processed) so a steady overflow is created. Wash the film for about 20 minutes. When you use a rapid roll-film washer, again, adjust the water temperature and place the reels containing the processed film into the washer. Adjust the rate of water flow until the reels start to turn. When the reels start to turn, adjust the rate of water flow until the reels stop turning. Set the timer and wash the film for about 5 minutes. 12. While the film is washing, rinse the processing tank, tank cover, and cap with clean water. Fill the tank with water (check the temperature) and add the wetting agent. After the film has been washed, place the film, still on the reels, into the wetting agent solution. Replace the tank cover and cap and agitate the film in the wetting solution very S-L-O-W-L-Y for 1 minute. 13. After 1 minute in the wetting solution, remove the loaded film reels from the tank. (Do not save the wetting solution.) 14. To dry the film, attach the end of the film to a film clip in the drying cabinet. Let the film unwind from the reel as you slowly lower the reel. When the film is unwound, depress the grip clip (if the reel has one) or remove the film from the core of the reel. Squeegee the film and attach a second film clip to the lower end of the film. Close the drying cabinet door and dry the film. Photographer's Data Sheets Sometimes a photographer's data sheet will accompany film that enters your imaging facility to be processed. The photographer's data sheet will provide you with information on how the film was shot, lighting conditions, and specific processing instructions. When a photographer's data sheet accompanies the film or job order, you should process the materials specified by the form. Cleaning Up 10-25 After processing, the darkroom and all equipment must be cleaned up immediately. Rinse thoroughly all processing equipment: tanks, reels, hangers, thermometers, funnels, and so forth, in clean, warm water. Place the clean equipment where it can dry before it is needed for the next processing run. Always keep the processing room shipshape. REVERSAL PROCESSING Normal processing of black-and-white film produces a negative; from this negative, a positive is made. However, by using the reversal process, you can produce a positive image directly on the black-and-white film. In the reversal process, a negative image is first obtained by developing the original latent image in a developer that contains a silver halide solvent. This developer dissolves some of the excess silver halides. After leaving the developer, the negative image is dissolved away in a bleach bath. The silver halides remaining are chemically "exposed" (fogged) and developed by a second developer that provides the positive image. Not all black-and-white films reverse well. Films that reverse well are Kodak Direct Positive Panchromatic Film 5246 (35mm), T-max 100 Direct Positive Film, and Kodak Technical Pan Films (35mm). Instructions for reversal processing of these films can be found in the Photo-Lab-Index. contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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