Where can I develop black and white film in Harbin?

Generally, a bigger old photo studio will do. It's been a long time since black and white. . . .

It's troublesome to wash it yourself. I'll send you a step to see if it works. . . .

First of all, the steps of developing black and white film

The steps of developing black and white film include developing, stopping developing, fixing, developing and drying. 1. Preparation of developer and fixing agent The developer consists of developer, protective agent, accelerator, inhibitor and solvent. Commonly used developers are Mitur, Fenidone and Chinoni. Fixing solution consists of silver halide solvent, antifouling agent, sulfur inhibitor and hardener. The commonly used silver halide solvent is sodium thiosulfate (also known as seawater)

If you don't want to make ammonium chloride yourself, you can also buy ready-made kits (dry powder and aqueous solution) from photographic materials stores. If you do it yourself, you should pay attention to the following points:

(1) Weigh each drug accurately according to the formula.

(2) Dissolve the drugs one by one according to the medication order specified in the formula, and put the second drug after one drug is completely dissolved.

(3) The developer is generally prepared in warm water of about 50 degrees. If the temperature is too high, the developer will be oxidized, and if the temperature is too low, the drug will not dissolve easily. Stop developing solution and fixing solution can be prepared in warm water of about 30 degrees.

④ It is normal that the developer is slightly brown after preparation, but the developer and fixer should be colorless and transparent. If it is found that the developer is dark brown like soy sauce and the fixing agent is yellow and turbid, it should be scrapped and reconstituted, and the drug quality and dispensing order should be checked.

(5) found developer, stop developer, fixer have impurities, should be filtered before use. The prepared developer should be sealed in a brown bottle and placed in a cool place. 2. Preparation of rolling instruments

For developing black and white films, there are:

(1) Washing basin and washing tank (also called developing tank) for developing film.

(2) Canned dark bags for fashion film pasting.

(3) thermometer, measuring cup and balance.

(4) darkroom safety lights for watching movies during the screening. If you roll at a fixed temperature, you don't need a safety light. If you are not sure, you can use a dark green safety light (you can also add 2-3 layers of green paper in front of the flashlight). When watching the film, you can see whether the separation line on the surface of the emulsion is black and white. If it is obviously clear, the development is moderate. Generally, film viewing should be carried out in 4/5 of the whole process, and the number of film viewing should not exceed 2 times, otherwise the film will produce fog.

⑤ If possible, you can buy a fixed clock for timing.

⑥ Safe darkroom. Because the development of black and white film is operated in a dark room (except cans). If there is no dark bag, the cans need to be absolutely dark, and there can be no corners, diffuse light and reflection. You'd better check it carefully before you roll it, or the film will have a second feeling.

Light, special effects, or make the film scrapped due to exposure. 3. Selection of formula

At present, there are dozens of formulas for developing black and white films in the world. Here are some commonly used formulas.

D-76 formula milk powder D-76R supplement

Water (about 50 degrees) ... 750ml 750ml.

Mi Tuer, 2 grams, 3 grams.

Anhydrous sodium sulfite100g

Chinoni .....................................

borax

Potassium bromide (Note 2)

Add water to 1000 ml.

note:

① D-76 is the most commonly used particle developing formula, which is suitable for developing films, films and pages. A negative with fine silver particles and rich layers can be obtained.

② No 0. 6g potassium bromide was added to the original prescription, which was increased according to the drug situation in China.

③ The development time can be shortened by half when borax is changed to 20g in the formula.

④ D-76R is the supplement of D-76 formula, and 30 ml of D-76R should be added to develop each roll of 120~ 135 film.

⑤ Gao Fancha film can be obtained by directly using D-76R supplement.

⑥ Shanghai, AD, Baoding 2 1 Set the film development conditions as 10~ 12 minutes, 20 degrees.

D-72 formula

500 ml of water (about 50 degrees).

Mi Tuer 3 grams

Anhydrous sodium sulfite, anhydrous sodium sulfite, anhydrous sodium sulfite

A few nuns12g.

68g anhydrous sodium carbonate.

Potassium bromide, 2g.

Add water to 1000 ml.

note:

Although this formula is a general formula for film and photographic paper, it is generally not used for developing film because of its coarse particles and large contrast.

② The original formula of Mi Tuer is 3. 1g, anhydrous sodium carbonate 80g and Australian potassium 1g, 9g.

③ When developing photos, normal contrast (20 degrees, development time about 4 minutes) can be diluted with 1: 1, and low contrast (20 degrees, development time about 4-6 minutes) can be diluted with 1: 2. For Gao Fancha or rapid development, there is no need to dilute, and the development time is 1-.

Stop developing liquid SBl2.

Water (about 30 degrees) ....................... 1000 ml.

30 ml glacial acetic acid.

Note: Stop displaying L/2- 1 min.

F-5 acid hard film fixer

Water (30 degrees) ........................................................... 600 ml.

240 grams of sodium thiosulfate

Anhydrous sodium sulfite 15g.

Glacial acetic acid (98%) ........................13.4 ml.

7.5 grams of boric acid.

Alum …………………………………………………………………………………………………………………………………………………………………………………………………………………….

Add water to 1000 ml.

note:

① The formula has long storage time, stable performance, rapid and powerful fixation, and can play a role in film hardening in summer.

(2) The preparation water temperature should not be too high. When it exceeds 50 degrees, there is a danger of sulfur precipitation in case of acid.

③ Fixed time, 10 minute can be fixed.

Preservation of formula name 1000ml

Stamping capacity

Half a bottle is bottled in a full basin, and the pot is washed in the basin.

D-72 3 months 1 month 24 hours 6 volumes 8 volumes

D-76 6 months 2 months 24 hours 5 volumes 8 volumes F-5 18 degrees 5 months 18 degrees 2 months 18 degrees 1 week 10 volume 12. 5. Washing and drying: two problems that should be paid attention to in washing. First, the water quality should be clean, free of iron and sand, otherwise it will affect the film quality. Second, the washing must be sufficient (generally, it should be washed in running water for about 30 minutes. If it is not running water, change the water every 30 minutes, a total of 6 times). Film drying can be solved in two ways: one is natural drying (provided that the indoor air is kept clear and clean), and the other is cold air blowing and infrared (mercury ball) drying box, which can greatly shorten the time. After drying, the negative can be rolled back (that is, the medicine film faces outward), and then it can be rolled forward after being enlarged and printed, so that the film is flat. Second, the common disadvantages of developing black-and-white film In the process of developing black-and-white film, we often encounter some unexpected problems, some of which are failures in the operation process, some are produced during shooting, and some are problems with the film and the liquid medicine itself. We should check carefully and find out the reason.

Common shortcomings in black-and-white film development are as follows:

1. Black film and large contrast: caused by too high development temperature or too long development time. The temperature of the medicine should be checked and the development time should be controlled.

2. The negative film is white and the image is weak: the development temperature is too low, or the development time is insufficient, or the developer is not oxidized. All three items should be checked.

3. Film scratch: The film is scratched during punching or developing. Avoid scratching during operation, especially when washing with water at last.

4. The negative film is opaque and black and white: the fixing is invalid or the fixing time is too short. Replace the new fixing solution or extend the fixing time.

5. Stripes on the negative film, uneven film: uneven stirring during development, or affected by indoor temperature difference.

6. There are wrinkles on the negative film, the washing temperature is too high or the temperature of developer and fixer is too high. Cool the water with epidural fixative to keep the drug at a constant temperature. 7. There are white spots or black spots on the negative film, and the developer, fixer or water contain impurities and fine sand dust. In order to prevent impurities, fine sand and dust, developer and fixer can be filtered, and the faucet can be filtered with cotton yarn to avoid dust sticking when drying. 8. Some negative films have images, and some are black: light leaks from darkroom or camera when shooting, or light leaks when shooting or loading films. Check darkroom and camera to avoid light leakage. Three, black and white film processing methods There are many kinds of black and white film processing methods, which are roughly as follows: basin processing, tank processing, deep box processing, film processing, and film processing. Now, two washing methods, basin washing and pot washing, are introduced as follows: 1 Pot washing is the simplest washing method, and porcelain pots and bowls can be used for washing. Although this method has some limitations, it is still adopted by photographers because of its convenient materials and low dosage of liquid medicine. To develop black-and-white films, only three basins (developer, developer stopper and fuser) are needed. As long as we pay attention to the change of seasonal temperature difference, we can develop the film with a water bath incubator (the same warm water or circulating water with fixed development temperature is put down in the developing basin). The following problems should be paid attention to when spraying:

(1) Developing black-and-white film must be done when it is completely black. Allow development to be viewed in dark green light.

(2) The number of films developed in a basin must be controlled. It is best to develop two rolls 1000 ml developer or one roll 135 at a time, and it is best to develop eight negatives (4x5). It is difficult to guarantee the quality of the film because of too much development.

(3) There are many ways to flush the basin, including pulling the end, that is, holding both ends of the membrane with both hands and unfolding it back and forth. Although this is easy for beginners to master, it is easy to scratch the film and is greatly affected by indoor temperature. It's best to use the loose pull mode, left-hand pull-tab and right-hand pull-tab, right-hand pull-tab and left-hand pull-tab, so that the film can always keep the shortest distance in the developer (Figure 1).

④ The basin punch is easy to strain or scratch the sad optical film, so be careful when operating.

⑤ When developing the film, the photosensitive film should face up, and when developing the page, the photosensitive film should face down, and then develop the film to prevent uneven development caused by bubbles.

6. Pot-washing utensils can't use iron pots, aluminum pot, copper pots, etc. Otherwise, its oxide will lead to negative pollution and spot marks during development. 2. The equipment of water tank flushing method is simple, as long as there is a flushing water tank. It is an economical, portable and practical washing method, which can be used by both professionals and amateurs. It is one of the most commonly used washing methods at present.

One. The washing tank is made of stainless steel or phenolic plastic (bakelite), which is acid-resistant, corrosion-resistant, cold-hot and has a certain strength. These two kinds of sinks are available on the market, and they are all round in shape.

Shape and square, the former is used to wash 120 and 135 volumes, and the latter is used to wash 4x 5 inch pages. Stainless steel washing tank is characterized by fast heat transfer and refrigeration, easy to raise or lower the temperature of developer, smooth chrome-plated surface, difficult adhesion of liquid medicine and easy cleaning. The parallel spiral of the shaft core is easy to master as long as the film is loaded correctly (Figure 2). As can be seen from the above, stainless steel washing tank has many advantages over bakelite washing tank, so it is most commonly used. The capacity of the developing tank can be roughly divided into four types: 250,500,1000,2000 ml. The smallest one can develop one roll of 135 film, and the largest one can develop eight rolls of 135 film. There is no need to set up a darkroom for film in dark bags, especially in the wild, which is very convenient to carry. The following matters should be paid attention to in the use of stainless steel washing tank: ① The filling part of the tank is the key. As long as the filler is suitable, there will be no dislocation and delamination. Beginners can practice with waste films at first and experience the essentials of film loading again and again. Over time, practice makes perfect. Wash your hands before film loading, and carefully check whether the film on the edge of the shaft core is derailed or misplaced after film loading. If the film is derailed, take it down and reinstall it. ② Due to its good sealing performance, the stainless steel washing tank is allowed to be completely immersed in a constant-temperature water tank for operation during the cleaning process, and can also be stirred in water, so that the washing tank is not exposed from beginning to end (Figure 3). This can ensure that the development is carried out at a constant temperature and reduce the influence of indoor temperature difference on the developed film. (3) If you want to use a stainless steel mandrel to develop two films back to back, you must remember that the photosensitive film must face outward, the film base and the anti-blooming layer should face inward, and never the other way around. If the operation is not skilled, it is better to punch holes roll by roll. When two rolls are developed back to back, the anti-blooming layer of the film is not easy to remove and needs to be washed.

Add a little alkaline anhydrous sodium sulfite or rinse for a while to recede.

(4) Before drilling, check whether the positioning nail of the shaft core clamps the film, so as to prevent the film from falling off, slipping out of the shaft core and scratching the film during stirring. ⑤ Immediately after film loading, inject the developer, and then rotate the shaft core several times in the opposite direction. Before putting in constant temperature water, turn it up and down a few times to eliminate bubbles and avoid membrane blooming (Figure 4). ⑥ Stainless steel flushing tank and shaft core should be handled with care. If it is stainless steel, it must not be dropped, rolled or bumped, otherwise the tank and shaft core will be deformed after a long time, which will affect the loading or cause light leakage. Bakelite washing tank has excellent thermal insulation performance, and the degree of cooling or heating is much slower than that of stainless steel washing tank. Because of this, some people like to use bakelite to wash the grooved roll. Bakelite washing tank has three kinds of shaft cores:

Belt type, screw type and fan type. Attention should be paid to the use of bakelite cleaning tank for rolling.

The following questions:

① The sealing condition of bakelite washing tank is worse than that of stainless steel washing tank, so it is not advisable to immerse the washing tank in a constant temperature tank, otherwise the developer will be diluted by water pressure into the washing tank.

(2) The wood washing trough will leak light if it is slightly neglected. Always check whether the connection between the cover and the fuel tank is tight.

③ It is difficult to install the wooden shaft core after it is wet and astringent. It is best to dry the water and install it when it is dry.

(4) Bakelite washing tank and shaft core should be soaked in water for 65 05 minutes after use, and kept clean to prevent pollution.