What are the differences and precautions when shooting color negative film and color reversal film?

1 Negative film and reversal film

The main difference between the two is: the light, shade and color of the image on the negative film are opposite to the actual scene; the reversal film is the same. If the purpose of shooting is mainly to develop photos, you should choose negative film, which is the most commonly used by people. Reversal film is mainly used to make slides or printing plates. Another difference from negative film is that it is more difficult to develop photos using reversal film. Nowadays, there are very few photo studios that can develop reversal films, and even fewer photo studios that can directly use reversal films to develop photos. There are only two or three in Beijing, and there is none in most provinces in China. And they use reversal films to directly develop photos. The price of photos is relatively high (in China, it is 3-4 times more expensive than developing negative photos). It is possible to copy a negative using reversal film and then use it to develop the photo, but it is still more troublesome.

The English difference between the two is: for negative film, add Color after the English brand, such as FUJICOLOR (Fuji Color Negative Film). For reversal films, the color is changed to chrome, such as Ektachrome (Kodak's Ekta reversal film). Another simpler identification method, although less formal but effective - you can always find the words C-41 on the packaging box or metal cassette of negative films; you can always find E on the box of reversal films. -6 words. But they are all small characters and not in conspicuous places. It is worth mentioning by the way: Negative film has a larger exposure latitude. Generally, good photos can be produced from negative films in the range of 3 stops over and 2 stops under; while reversal films generally only have half a stop over and half a stop under. Tolerance, beyond this limit the image effect will be significantly worse.

People always think that only professional photographers use reversal film, but this is not the case. In this regard, we might as well imagine: in a slightly lingering and gloomy living room, the background music is Chopin's piano, amidst the aroma of old whiskey, slideshow images gradually fade in and out on the wall, and the voices of friends chatter loudly. Sometimes low, sometimes sparse, sometimes slow - whether it is travel photos or artistic photography, this will be a very meaningful process, and it is also more tasteful than playing videos or watching albums. Why not also sell a few reversal films and give it a try? The price of a slide projector is only between 1,000 and 8,000 yuan.

2 Sensitivity

Films have different sensitivities according to their sensitivity to light. The 21/100° often seen on film boxes is the sensitivity of this film. Among them, 21 is the German unit, called "fixed", and 100° is the American unit, called "degree". Later, they were combined to form the current international standard sensitivity unit. However, most films today still use "degree" as a conspicuous mark. It is worth remembering that every increase or decrease of 3 degrees and a doubling of the degree means that the sensitivity has doubled. When shooting, you need to reduce (increase) the aperture by one level or reduce (increase) the shutter time by one level. . 18/50°, 21/100°, 24/200°, 27/400°, 30/800°, 33/1600° are the more commonly used ones. The lower the sensitivity of the film, the better the image quality; but it must be at the expense of longer shutter time, and the longer the exposure time, the easier it is to take blurry photos. The short and long length of high-sensitivity film is naturally the opposite of that of low-sensitivity film. Except for the more professional photographic equipment stores, most of the color negative films sold on the market are 21/100°, and whether it is negative film or reversal film, film with this sensitivity is the cheapest. However, it is not uncommon for fake films to be sold at stalls in tourist areas, and it is difficult for non-professionals to distinguish between genuine and fake films.

3. Light type and daylight type

Only color film can be divided into light type and daylight type. This distinction is particularly important in reversal films. Light films are suitable for shooting under incandescent lighting (higher wattage is better). If you shoot under daylight, the image will be severely bluish. Sunlight films are suitable for shooting in daylight, but if they are taken under lights, they will become seriously yellowish. However, whether it is a light film or a daylight film, it will be difficult to take photos with normal colors under so-called fluorescent lamps. Because fluorescent lamps do not have a continuous spectrum, they are not easy to correct. Illuminated film boxes must be marked with the word Tungsten more conspicuously; daylight film is marked with the word Daylight, but it is generally not as eye-catching as the former. However, no matter what the light source is, the flash should match the daylight film; photos taken with direct flash illumination often have dull light effects and lack of taste, so you should try not to use flash lighting. The reason why the division between light type and daylight type for negative films is not strict is because it is easier to correct the color during the photo development process.

4 Professional and amateur types

Both negative and reversal films are divided into professional and amateur types. The image quality of professional films is better than that of amateur films, but the price is also much higher. If stored for a long time, it should be placed in the refrigerator. Professional (some films add s after the word) is a mark for professional films, while amateur films generally do not have this mark. Of course if you have money, you should buy professional films.

5. A kind of film that cannot be developed in China

Most of the Kodak reversal films sold and used in China should be "Kodak Ektachrom" Ektachrome)".

Kodak's top professional reversal film is undoubtedly "Kodakchrome". Although this film is good, it can only be developed in the United States and a few countries. In foreign countries, the selling price of this kind of film includes two types: those that include processing fees and postage fees, and those that do not. This kind of film cannot be developed not only in mainland China, but also in Hong Kong. Because it uses an "external" flushing process, and this process is a patented process that Kodak strictly keeps secret and never spreads to others, and there are certain environmental reasons, resulting in its poor popularity. However, professional photographers in Europe and the United States commonly use this film. In short, no matter what the reason, if you come across this kind of film, you must treat it with caution. It is quite troublesome to shoot a few films in China and have to ask someone to take them abroad for development.