Black
and White Print Process
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Process
Times for Black and White Prints
Process
Sequence for Black and White Prints
Process
Information for Black and White Prints
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Process Times for Black and White Prints
- Rotation Speed (with reversing directions) 'P'/75 for 1500 and
2800 drums, '4'/50 for 3000 drums
- Temperature 20°C (68°F)
- Pre-Rinse 0:30
- Developer 1:30 (Time will vary with choice of developer and
paper)
- Stop-Bath 0:30
- Fix 1:00 (Time will vary with choice of fixer and paper)
- Rinse 2:00 (4x 0:30) (see note below)
- Dry As needed.
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Process Sequence for Black and white
Prints
Pre-Rinse
The drum and paper are brought to process temperature. The emulsion is completely soaked
with water.
Developer
Exposed silver salts are converted to metallic silver. Density and contrast are determined
in the developer.
Stop-Bath
The stop-bath quickly and evenly ceases development. The emulsion is made acidic for the
fixer.
Fixer
The fixer removes the unconverted silver salt.
Final Rinse
This rinse removes the fixer from the emulsion. Removal of the fixer is necessary for
image permanence.
The rinse should be a series of 30-second changes of water.
The 2:00 rinse would be four complete changes of water. Each change of water should be
about 1 1/4 to 1 1/2 times the volume of chemicals used.
Dry
As needed.
Both the developer and the fix times will vary with the
manufacturer's directions for the use of their product. For optimum results, select a
paper developer type and dilution that has at least a one minute development time at the
processing temperature used.
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Process Information for Black and
White Prints
Making prints from negatives. The JOBO processor can also be
used for papers and chemicals manufactured by Kodak, Ilford, Agfa, Oriental, etc. JOBO
also has a line of black and white chemicals made by Tetenal.
JOBO does not recommend processing Fiber Based print paper in
our print drums. The raised ridges on the inside of the drums may mark the paper, and
rinsing in the drum may not be satisfactory.
It is good practice to be consistent in processing
procedures. However, it may be useful to know that with the exception of the developer (or
toner, if used), all steps in the black and white resin coated print process are 'taken to
completion.' That is, once the action of the chemicals or rinse has done what it is
supposed to (had its effect), further time in the bath or rinse will have no additional
benefit or harm. If you are to error in the timing of the process steps other than the
developer (or toner, if used), it is safer to go longer, not shorter. Be aware however,
that very long (over 20 minutes) immersion times for resin coated paper in any solution or
water could cause frilling or discoloration at the edge of the paper and other problems,
and should be avoided.
JOBO paper drums have a chemical quantity printed on the side
stating the minimum amount required to cover the paper during processing.
With black and white prints, there is no chemical (at
recommended dilutions) that would require more solution quantity than printed on the drum.
It is safe to use the quantity printed on your JOBO Drum. If you are using extended
dilution of the processing chemicals, check with the manufacture's quantity requirements.
In all cases use at least the volume required by the print drum or the chemical-dilution
used.
You may add toning procedures to the black and white print
process in your processor. Follow the manufacturer's recommendations on times for the
additional steps.
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If you have any questions, contact us utilizing one of the
following methods:
Equipment or Processing Questions:
- Phone: Customer Service Department (734) 205-9421
e-mail: tech@jobo-usa.com
Repair Questions:
- Phone: Repair Department (734) 205-9420
- e-mail: repair@jobo-usa.com
- Telephone (734) 677-6989
- Fax: (734) 677-6963
-
- Postal address
- P.O. Box 3721, Ann Arbor, MI 48106
- Shipping Address
- 4401 Varsity Drive, Suite D, Ann Arbor, MI 48108
- Electronic mail
- Sales: sales@jobo-usa.com
- Equipment & Processing Questions: tech@jobo-usa.com
Repair Information: repair@jobo-usa.com
- Shipping or Billing Questions: help@jobo-usa.com
Webmaster: webmaster@jobo-usa.com
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