銀鹽感光乳劑配方與制作方法

Instructions for Making a Simple Silver-Based Photographic Emulsion Suitable for Coating on Glass or Film制作簡單的可涂抹在玻璃或膠片上的銀鹽感光乳劑Ingredients: Gelatin, potassium bromide, potassium iodide, and silver nitrate.成份：凝膠（明膠），溴化鉀，碘化鉀，硝酸銀Equipment: film or glass plates, metal plates, plastic stirring paddle, cheesecloth, gloves, safelight with light red filter (Kodak 1A or equivalent), 1 liter glass beaker or stainless steel bowl, 4 liter glass beaker or equivalent stainless steel bowl. A mechanical stirrer would be useful, but is not essential.器具：透明膠片或玻璃板，金屬板，塑料攪拌器，粗棉布，手套，安全燈（紅色），1升的玻璃大口杯或不銹鋼杯，4升的玻璃大口杯或等大的不銹鋼杯，以及一個藥品攪拌勺也許會派上用場。1. Dissolve the gelatin. Dissolve 10 grams of gelatin in 360 ml warm distilled water.1溶解凝膠：用360ml的溫蒸餾水溶解10克凝膠。2. Dissolve the potassium bromide and potassium iodide. Add 32 grams of potassium bromide and 0.8 gram potassium iodide to the gelatin solution and stir until dissolved.2溶解溴化鉀和碘化鉀：將32克溴化鉀和0.8克碘化鉀放入凝膠溶液，并不斷攪動直到溶解。3. Heat the solution. Heat the mixture to 130o F (55o C). The solution must be maintained at that temperature. The simplest way to do this is to surround the solution with a water bath.3加熱溶液：將上述溶液加熱到55o C，并保持該溫度。最簡單的辦法是水浴法。4. Lights out. Turn out normal lights and work under a light red safelight.4關燈：關掉普通的燈，打開安全燈。5. Make a solution of silver nitrate. Wear gloves when working with silver nitrate. Dissolve 40 grams of silver nitrate in 400 ml distilled water.5配置硝酸銀溶液：此時需要戴上手套。將40克硝酸銀放入400ml蒸餾水中，并溶解。6. Combine the silver nitrate and gelatine solutions slowly. This is known as the precipitation stage. Add the silver nitrate solution slowly to the gelatin solution at a rate of 20 ml every 30 seconds for 10 minutes, stirring constantly. The more slowly the silver nitrate is added, the larger will be the silver halide grains producedand the larger the grains, the faster the emulsion.6混合兩種溶液：這是個比較倉促的階段。把硝酸銀溶液緩慢的倒入明膠中，大約以30秒20毫升的速度持續(xù)10分鐘。傾倒硝酸銀溶液的速度越慢，銀鹽的鹵化物生成的越多，從而感光度也越高。7. Ripen the mixture. Keep the solution temperature at 130o F (55o C) for a further 10 minutes, then allow to cool slowly to 104o F (40o C). The ripening process allows the size of the silver grains to grow, increasing the emulsion speed. Heat speeds the ripening. (The mixture can also be cooled until it gels and stored overnight at this point. Simply reheat to 104o F (40o C) when ready and proceed with step 8.)7使混合溶液熟化：使混合液的溫度保持在55o C，并保持10分鐘，然后使其冷卻到40o C。這個過程會使銀鹵化物增加，并使感光度增加。加熱會使熟化過程加速。（也可以讓混合溶液冷卻直至形成膠體，并儲存一晚。在進行步驟8時，可以簡單的重新加熱到40o C）8. Swell additional gelatin. Soak 40 grams of gelatin in distilled water until softened (20-30 minutes), then pour off the excess water.8增加明膠：用蒸餾水溶解40克明膠，并使其軟化20到30分鐘，然后倒出多余的水。9. Combine the solutions (emulsification). Add the softened gelatin to the silver nitrate solution and mix thoroughly. Cool the mixture and allow it to set (this usually takes 2 to 4 hours).9結合兩種溶液：把軟化的明膠（步驟8）加入硝酸銀溶液（步驟7）中，持續(xù)攪拌，直至混合溶解。靜置，并冷卻混合液，一般需要靜置2到4小時。10. Strain through cheesecloth. Place the emulsion in a square of cheesecloth and fold the cloth over it. Hold the emulsion in a pan of cold water and twist the cloth so it is squeezed through the pores in the cheesecloth, making a kind of gelatin spaghetti. This is necessary in order to remove excess silver salts.10用粗棉布積壓：把做好的感光劑放到一個方形的粗棉布（我想用紗布也可以吧）中，并將其折疊。把感光乳劑放入冷水中，擠壓棉布，使乳劑從不中擠出，就像做意大利面條一樣。這樣做很有必要，作用是去除乳劑中多余的銀鹽。11. Leach out the excess salts (halides). Pour off excess water and place the shredded emulsion in a large beaker or other container. Pour 3 liters of cold water (below 68o F or 20o C) onto the shredded emulsion, let it sit for 2.5 minutes, then pour off 2 liters of the water and add 2 liters of fresh water. The use of distilled water is recommended, to reduce the possibility of unknown contaminants in the emulsion.11去除多余的鹽：倒出多余的水，不作成面條狀的乳劑放入大燒杯（或較大的容器）中。倒入3升冷水（20o C），靜置兩分半鐘，然后倒出2升水，再倒入2升干凈的冷水。建議是用蒸餾水，以避免未知物質(zhì)對感光劑的污染。12. Repeat. Repeat the washing process 5 times, using cold water. Pour off the excess water.12重復：用冷水重復水洗過程（步驟11）5次，然后倒出多余的水。13. Melt and after-ripen. Melt the emulsion by heating to 130o F (55o C) for 15 minutes, then slowly cool it to 104o F (40o C). The after-ripening doesnt increase grain size much, but does increase speed.13熔化和二次熟化：把乳劑加熱到55o C,并保持15分鐘，然后冷卻到40o C。二次熟化的過程不會使乳劑的體積有明顯增加，但會提高乳劑的感光度。14. Coat. For a 3? by 4? inch glass plate, use 4 ml of emulsion solution. Pour it on the glass and spread it unformly. This formula should make enough emulsion for approximately 100 such plates.14涂抹乳劑：一般一個3.5 X 4.5 英寸的玻璃板，需要使用4毫升感光乳劑。把乳劑倒在玻璃上，并均勻涂抹。這個配方足可以涂布100個這樣大小的玻璃板。15. Chill. Place the coated glass on a level cold metal plate until the emulsion sets, then place in the dark to dry.15冷卻：把涂抹了乳劑的玻璃放在水平的金屬板上知道乳劑凝固，然后再把這些玻璃板放到無光的地方使其干燥。16. Expose. Make your first test exposure at 1/30 second at f/8, and adjust up or d