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These hints are assembled from questions
we are most often asked and problems we most often encounter.
Solutions are from the experiences of Wolfe's personnel
and helpful customers. Due to variations of personal taste
and limited information sources, not all suggestions will
work for everyone.
BASIC PROCESSING STEPS
Production of black and white photographs
is divided into film processing and print processing.
Film is exposed to light (using your camera). The processed
film becomes a negative which is used to produce a positive
image on photographic paper (photo print) using a contact
frame or an enlarger.
Film processing is usually divided into:
DEVELOPER--a chemical that reacts with
the exposed silver on the film turning it black, which
creates the negative image.
STOP--does just that-stops the action of
the developer. This step reduces carry-over contamination
of the fix/hypo (next step).
FIXER--also called hypo, clears off the
undeveloped silver (shadow areas) of the film, and makes
the film permanently insensitive to light.
HYPO NEUTRALIZER--a chemical solution that
speeds up the release of fixer from the film during washing
to shorten wash time. Many permit 5 minutes or less wash.
It is used between the fixer and wash steps.
WASH--this plain water rinse dilutes and
removes the fixer solution from the film. The length of
time and amount of water used in this step can be reduced
by using a hypo neutralizer bath before starting the washing.
PHOTO-FLO--a wetting agent that reduces
surface tension, allowing water to flow off without leaving
drops that dry to form spots on the film emulsion. These
dried spots from regular water without photo-flo will
not wash off and usually cannot be removed with film cleaner.
FILM PROCESSING TECHNIQUE
DEVELOPER HINTS--most experts recommend 5 seconds
agitation every 30 seconds throughout the development
time for film processed at normal ratings. All agitation
should be at a moderate rate--if you shake the tank too
violently, streaking can result.
PREVENTING AIR BUBBLES--pouring solutions
into a daylight development tank cantrap air on
the film. Always tap your tank on a solid surface to dislodge
air bubbles (also called air bells) when you've poured
in a solution to start the processing. If the bubbles
are allowed to remain they will appear as small clear
or lighter circles on the negative after processing is
complete. If you're having trouble with bubbles try these
ideas. Before you start to process the film, try a short
presoak (1 to 2 minutes) in water or water with a few
drops of photo-flo added. If film is excessively dry,
bubbles stick tighter and presoaking will usually allow
them to float off as the developer is poured in. Avoid
using freshly mixed developer, especially if your mixing
faucet has an aerator. Don't shake up developer before
using it. Air added to developer by the aerator
or by shaking can cling to the film, causing spots.
STOP BATH-ACETIC ACID or PLAIN WATER?--as
in most processes there are two (at least) schools of
thought. One of these is that to minimize fixer contamination
from developer carried over the film, an acid stop is
most effective (1/2 oz. of 28% acid per quart of water).
Photographers striving for the ultimate in fine grain
usually use plain water. Time for either method is 30
seconds to a minute.
FIXER--rapid fixer is preferred since it
reduces fixing time and is harder fixing. Fixing time
is 2-5 minutes in rapid fix compared to 5-10 minutes required
in regular fixer. Extra hardening in the fixer is desirable
for finer grain and a more durable emulsion surface. If
the fixer is old (over 30 days) twice the clearing time
is the minimum recommended time. Clearing time is the
time the film takes to lose its creamy gray or pink color
in the clear areas. Cream colored areas in dry film indicates
insufficient fixing or exhausted fixer. If this happens
to you, refix (in fresh fixer) and rewash to clear the
film.
WASH--for archival permanence (film that
will not begin to fade in a few years or less), at least
30 minutes is recommended in a good film wash. For a fine
grain, a shorter time such as about 10 minutes is better,
as the grain (clumps of silver that form the film image)
tend to swell while wet. Use of a hypo neutralizer can
reduce wash time to below 3 minutes. Orbit Bath and Hustler
are both easy to use liquid neutralizers.
DRYING--many people use distilled water
in their photo-flo due to the dirt in Topeka's water.
This is especially advisable in summer. A squeegee will
also take off extra crud on film, but be careful to keep
the squeegee clean. Dirt caught on the squeegee can scratch
the film. Once dirt has dried on the film emulsion, it
often will not come off. Do not fast dry film with a room
heater or hair dryer. This can cause significant grain
increase. A room heater or hair dryer at several feet
away, or just a fan, will speed up drying if needed. It
is best to cut and file film immediately after it is dry.
If it is rolled up and stored, often the curl is hard
to get back out.
SPECIAL PROCESSING HINTS
1. Less frequent agitation will produce
lower contrast in your negatives. Because of less chemical
activity there will also be some increase in processing
time. The HC110R chart following this section shows times
and agitation for good push processing results.
2. The higher 72 degrees to 75 degrees
processing temperatures give shorter processing time with
no increase in grain. Use all steps at whatever temperature
you start with.
3. Pull processing: Sometimes it is desirable
to reduce film speed in development. When it is done intentionally,
it is usually to give an expanded tonality to the film.
When it is done accidentally, the film is pulled to save
incorrectly exposed film. Reducing developing time by
20% gives approximately one stop speed reduction, or 1/2
of the ISO rating (example: ISO 400 becomes ISO 200).
Because the tones extend excessively with excess overexposure
and extreme under processing, more reduction is not recommended,
however 2 to 3 stops of overexposure will normally be
printable with about 30% reduction from normal processing
time. Do not reduce time on T-Max or other flat grain
film. A 10% time reduction can cause serious contrast
has and over 1 stop speed loss.
4. Paper backed roll film, such as 120,
seems to process slower than their 35mm counterparts.
For best results, try about 10% time than for the 35mm
version of the film.
CORRECT EXPOSURE UNDER LOW LIGHT
1. Averaging reflected meters as used in
most 35mm cameras generally read one stop too low on football
arid basketball. In unfamiliar locations it is best to
push one stop further than the meter reading (for example,
if your meter is set for ISO 1600, process for ISO 3000).
2. For theatrical performance, when a spot
light is being used, process for half the film speed the
meter is set at (example, with meter set for ISO 1600,
process for ISO 800). This does not apply to stages with
even or full stage illumination, where your meter should
be correct.
3. When pushing other than 400 speed film
exposed indoors, process for one stop higher than meter
rating (example: Plus-X shot indoor at ISO 250 should
be processed at ISO 500). This does not apply to flash
and daylight. Most 400 speed films have increased red
sensitivity for tungsten exposure. Most slower films do
not, so they need extra exposure under light bulb illumination
only.
KODAK T-MAX FILMS AND DEVELOPER
T-MAX AND SIMILAR NEW FILMS
A new category of black and white films
have been appearing in the 90's. Called T-grain, flat
grain, tabular grain or similar labeling, it so far is
in most color films but only Kodak T-Max series and Ilford
Delta series black and white films, It is finer grain
than it's standard grain counterparts and being thinner
emulsion is considered to have higher resolution.
Some unique traits of these films: (1)
normal processing requires longer time than standard film.
(2) fixing requires about twice as long as previous films.
(3) It easily pushes one stop with only a slight additional
time increase from normal. (4) Response to various developers
is not the same as traditional films. For example. Kodak
HC-110R, recommended for extreme push with Kodak Tri-X
and Ilford HP-5 does not push T-Max film nearly as well.
Response to D-76 and the special T Max developer is excellent
however. (5) In printing, it may he hard to tell the emulsion
from the backing. The emulsion has a sheen rather than
being dull, and the back is matte coated for retouching,
so both have a semi dull appearance. If in doubt look
at the numbers on the film edge and get them right side
up.
IT'S NOT 3200! Kodak places a "P'
before the film speed on several films they make to show
that the rating is not the normal rating, but a rating
the film can be ''pushed'' up to and still maintain excellent
quality. The true rating for P-3200 is ISO 800-1000.
KODAK T-MAX DEVELOPER
An easy to use liquid developer providing
excellent results with popular black & white films,
especially compatible with T-Max films. Excellent results
with 1 and 2 stop push, moderate quality for 3 stop push.
We do not recommend more than 3 stop push or 21 minutes
processing due to what appears to be a chemical absorption
causing a fog that noticeably reduces negative quality.
For use, Kodak recommends 1:4 dilution.
Our tests have been run at 1:4 or, when using small stainless
tanks (8 ounce or 16 ounce) 1½ ounces developer
with 61/2 ounces water to achieve an even figure for easier
measurement.
In order to reduce the cost of chemistry,
Kodak does suggest the following: ''For non-critical use,
developer life can be extended by adding one minute to
the time for each process run (maximum of three). For
example: RoIl 1 in 8 oz. of developer 7 min. Roll 2 in
the same solution 8 min. Roll 3 in the same solution 9
min. After three rolls, the developer should be discarded.''
We would add (1) if you are push processing,
you will exhaust the developer faster, so greater time
increase would be required. (2) Kodak does not clearly
state keeping ability of used developer. They do give
the time for keeping of a mixed working solution in a
half full bottle at 2 months, so we would expect that
mixed, used solution in a full bottle could he used possibly
as much as a month later. If the pictures are important,
2 weeks or less based on the chemical still being about
the same color as when poured in the bottle (if it gets
darker, use becomes more questionable).
SUGGESTED DEVELOPING TIMES FOR
T-MAX DEVELOPER DILUTED 1:4 AND D-76 STRAIGHT
|
Film
|
ISO Rating
|
Temp/Time
|
| T-MAX |
|
100 |
400 |
P3200 |
68 Degrees |
75 Degrees |
| normal |
100 |
400 |
1000 |
9 min. |
8 min. |
| 1 stop push |
200 |
800 |
1600 |
12 min. |
10 min |
| 2 push stop |
400 |
1600 |
3200 |
17 min. |
15 min. |
| 3 push stop |
N.R. |
3200 |
6400 |
N.R. |
21 min. |
|
| Tri-X/HP-5 |
400 |
8-1/2 min. |
7-1/2 min. |
| 800 |
12 min. |
10 min. |
| 1600 |
17 min. |
15 min. |
| 3200 |
N.R. |
21 min. |
|
| Fuji 1600 |
1600 |
8-1/2 min. |
7-1/2 min. |
| 3200 |
14 min. |
12 min. |
|
| Plus-X |
125 |
7 min. |
6 min. |
|
| Other Films |
normal |
8 min. |
7 min. |
| 1 stop push |
12 min. |
10 min. |
Agitation is 15 seconds the first minute and 5 seconds
every minute after that for normal and 1 stop push. To
reduce contrast increase, drop to 15 seconds the first
minute and 5 seconds every minute after that for higher
speed pushing.
EKTAGRAPHIC SLIDE FILM
Ektagraphic Slide film is called a slide
film because the high contrast negative images
are often used as 35mm projection slides. Black type or
graphs photograph as clear and
the white background photographs black. In long rolls
(bulk film) and sheet film this film
is also sold as Kodalith type 3 film.
Following are some hints to making the
best use of this material:
(1) Exposure is extremely critical, less
than ± ½ stop latitude. The film is extremely
slow, about ISO 6-8 with photo floods, slightly faster
outdoors
(2) Kodalith developer provides the blackest
black with clear whites. Use about 3 min. at
75 degrees. Kodak Dektol or Ethel LPD paper developers
diluted 1:1 from stock solution provide satisfactory results
for experimenting developed 3 min. at 75 degrees but is
likely to pinhole.
(3) Color effects can he added to the clear
areas of Kodalith slides quite easily. Dr. P.R.
Martin's water colors are designed specifically for this
application. For less critical applications, food coloring
will color the entire slide by simple immersion of the
slide. Felt
markers will work but usually show streaking.
TECHNICAL PAN FILM
Technical pan is high contrast film that
can be used for very high contrast negatives (not
as contrasty as Kodalith), high contrast, or normal negatives
with extreme fine grain and
sharpness. Following are some basic time and chemistries
at 75 degrees. Because of the critical exposure required
by this film, you may need to make adjustments to fit
you particular equipment.
- Very High contrast with ISO 200: HC110 Dil B 9
min.
- High contrast-ISO 100-Develop normal time for regular
film.
- Medium contrast-ISO 25-32-Technidol 8 min. or FG-7
1:31 10 min.
or Rodinol 1:130 12 min.
FILM PROCESSING CHARTS
Suggested Processing Times With Popular
Film Developers
Basic processing times for normal processing
of most films with some common developers. Add 10% to
these times for high speed films such as Tri-X and HP-5.
Subtract 10% for PIus-X only. Add 20% for all T-Max
films.
| Developer |
68 degrees |
75 degrees |
| Microdol-X |
9 minutes |
7¼ minutes |
| Microdol-X 1:3 |
12 minutes |
9 minutes |
| Il ford Perceptol |
13 minutes |
9 minutes |
| D-76 |
7 minutes |
6 minutes |
| D-76 1:1 |
9 minutes |
7 minutes |
| Edwal FG-7 1:15 |
12 minutes |
9 minutes |
*We have used FG-7 with high speed films
at normal ratings using the recommended adjustment above
with no problems. FG-7 gives additional directions for
pushing and for using sulfite additive in the developer
instructions. Use of sulfite may give finer grain with
high speed films.
Push processing times for D-76 with Tri-X, HP-5 and
T-Max 400
| IE Rating |
68 degrees |
75 degrees |
| ISO 800 |
12 minutes |
9 minutes |
| ISO 1600 |
18 minutes |
13 minutes |
| ISO 2000 |
20 minutes |
15 minutes |
Processing with HC110 Developer or HC110 Replenisher:
1. HC110 Developer dilution B or:
2. HC110 Replenisher diluted 1:31 (1/4 oz makes 8 oz.
developer) from one pint concentrate or 1:3 from prepared
replenisher. Agitate for 5 seconds every minutes. Use
72 degrees temperature.
| Film |
Speed |
72 degrees |
|
Tri-X/HP-5
|
ISO 400 |
7 minutes |
| ISO 800 |
10 minutes |
| ISO 1600 |
15 minutes |
|
Plus-X
|
ISO 125 |
5-1/4 minutes |
| ISO 400 |
10 minutes |
| Most Other Films |
Normal |
6 minutes |
|
Fuji 1600
|
ISO 1600
|
7 minutes
|
|
ISO 3200
|
11 minutes
|
For high speed push as follows: use only
HC110 Replenisher. HC110 Developer will require longer
times and may not work at all for highest times. Agitate
at start, when 1/3 time elapsed and when 2/3 of time elapsed
only.
1. HC110 Replenisher diluted 1:15 (1/2
oz. makes 8 oz. developer) from pint concentrate, or:
2. HC110 Replenisher from prepared solution dilute 1:1.
| Film |
Speed |
72 degrees |
|
Tri-X/HP-5
|
ISO 1600 |
7 minutes |
| ISO 2400 |
10 minutes |
| ISO 3200 |
15 minutes |
|
Fuji 1600
|
ISO 5000
|
10 minutes
|
1. HC110 Replenisher diluted 1:7 (1 oz.
makes 8 oz. developer) from pint concentrate, or:
2. HC110 Replenisher direct from prepared solution.
| Film |
Speed |
72 degrees |
|
Tri-X/HP-5
|
ISO 4000 |
7 minutes |
|
Agfa 400
|
ISO 6000
|
10 minutes
|
|
ISO 8000
|
15 minutes
|
*T-Max 400 does not push well in HC-100.
We recommend T-Max developer for best push quality with
T-Max films.
ACUFINE And ETHOL UFG Developers
Acufine and Ethol UFG are popular push
processing chemistries in addition to the two charts on
this sheet. Most people feel their times give weak
negatives. We suggest adding 1/3 to 1/2 to their
times to get more satisfactory negatives. Another
way to correct this is by using 1/2 the film speed recommended
by their data.
Samples times with popular films.
| Film |
Speed |
68 degrees
|
75
degrees |
|
Tri-X/HP-5
|
ISO 400 |
4-1/2 minutes
|
3-1/2 minutes |
| ISO 1000 |
7-1/2 minutes
|
6 minutes |
|
Plus-X
|
ISO 250 |
6 minutes
|
5 minutes |
| Popular films |
2X Normal |
6-1/2 minutes
|
5-1/2 minutes |
AGFA RODINOL -- A CLASSIC
This is a unique black & white developer
having some unusual characteristics that can be very useful
for special situations:
(1) Rodinol is a high resolution developer.
It's enthusiasts consider it to produce the sharpest grain
pattern of any developer available. This is not to be
confused with line grain, Rodinol produces moderate grain
with a sharp diamond edge shape. The extreme detail makes
this an excellent combination with fine grain films such
as T-Max 100, llford Pan-F and Panatomic-X.
(2) Reduced, normal and pushed processing
times are all possible with Rodinol. A word of caution
about pushing. Rodinol is a "cannibalistic"
developer. It actually consumes the silver off your film.
The push processing time recommended below probably will
not produce a black in the highlights no matter how much
the overexposure. With increased time, you may actually
process long enough to produce clear film, the entire
silver having been consumed.
(3) It is surprisingly moderate, in cost
due so the high dilution used. If you use the mantifacturers
recommendation, try 10-20% overdevelopment as most mfgr.
recommendation produce slightly thin negatives.
HERE'S A FEW SAMPLE TIMES FROM OUR OWN USE
Normal processing with most films 1:63 dilution
10 minutes at 75 degrees
Tri-X/HP-5 rated at ISO 2000 or 1:31
dilution 17 minutes at 75
degrees
Fuji 1600 rated at ISO 4000
The choice of odd dilution is for easy conversion to
ounces for 8 ounce tanks. 1/8 ounce in an 8 ounce
tank or 1/4 ounce in a 16 ounce tank for 1:63.
PROPER AGITATION
To reduce the chance of streaking that
can occur with single direction agitation, it is best
to rotate your inversion tank at the same time as you
are inverting it, as shown in this illustration. Normal
agitation should be three inversion/rotations and should
take about 5 seconds. Don't forget to tap the tank at
least once near the start of processing to dislodge air
bells.
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