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SPECIAL FILMS
Apart from the normal , limited ranges of black - and - white emulsions there are a number of others made for special purposes . While none of them could serve as a photographer's regular film stock , they are ideal for certain specific situa- tions . In addition , simply by producing a different kind of image , they can be valuable for occasional use as a means of injecting new graphic interest into an image .
KODAK RECORDING FILM 2475
Rated at ISO1000 , this special emulsion is designed for low - light photography sacrificing quality for the ability to record an image . It is extremely grainy , even at a small enlargement , and has extended red sensitivity for better perfor- mance with available tungsten lighting , which is orange .
ILFORD XP - 1
This is a chromogenic film , that works on a similar principle to colour negative emulsions . The original silver image is replaced with dyes , to give an image free of the traditionally distinct grain . More importantly , it has latitude than normal silver - image films , and can tolerate massive under- and over - exposure . It needs to be processed in colour negative chemicals , however , or its own special developer .
AGFA DIA - DIRECT
With reversal processing , this slow ( ISO32 ) emulsion gives a projectable mono- chrome - transparency , intended for use in slide shows .
ABOVE Kodak's High Speed Infrared film has extended sensitivity beyond the longest visible wavelengths . With a 25 red filter , as here , scenes look more natural than if a visually opaque filter were lenses feature a red focusing mark on the barrel for use with infrared film .
LEFT When used with the appropriate high - contrast developer , Lith film produces a negative that has only two tones ; clear and black . The film can be used to print , for example , silhouettes . Varying exposure simply alters the relative proportions of black and white in the image .
FAR LEFT An image captured on Ilford XP - 1 , a chromogenic film related to colour negative emulsions XP - 1 can take massive under - and overexposure and still result in images with relatively fine grain . However , it needs to be processed in colour negative chemicals .
INFRARED
Kodak's High - Speed Infrared has extended sensitivity beyond the longest visi- ble wavelengths . When used with a visually opaque filter ( Wratten 87 or equi- valent ) , it can give startlingly unusual renditions . Certain surfaces and materials reflect infrared wavelengths quite differently from visible light , so that on this film they appear lighter or darker than expected . Healthy green vegetation , for example , is very bright , while blue sky is almost black . With a 25 red filter , or none at all , the visible wavelengths dominate , and the results look less unusual .
High - Speed Infrared film is not easy to use . It needs careful storage ( at low temperatures ) and protection from light to the extent that even the cassette should only be handled in darkness . Most lenses are not perfectly corrected for chromatic aberration , and focus infrared rays at a different point from ordin- ary light ; be careful to use the red focusing provided for this purpose on the barrels of most such lenses . The emulsion also has a very coarse grain .
LITH FILMS
These are , strictly speaking , not designed for normal camera use , but can give interesting and dramatic results if you do . They are intended for various kinds of special darkroom procedure ; used with the appropriate high - contrast devel- oper , they produce a negative that has only two tones : clear and black . This film can be used for slide projection ( the best way of making titles ) or printed to give , for example , perfect silhouettes . Varying the exposure simply alters the relative proportions of black and white in the photograph ; there are no inter- mediate tones .
SPECIAL FILMS
Apart from the normal , limited ranges of black - and - white emulsions there are a number of others made for special purposes . While none of them could serve as a photographer's regular film stock , they are ideal for certain specific situa- tions . In addition , simply by producing a different kind of image , they can be valuable for occasional use as a means of injecting new graphic interest into an image .
KODAK RECORDING FILM 2475
Rated at ISO1000 , this special emulsion is designed for low - light photography sacrificing quality for the ability to record an image . It is extremely grainy , even at a small enlargement , and has extended red sensitivity for better perfor- mance with available tungsten lighting , which is orange .
ILFORD XP - 1
This is a chromogenic film , that works on a similar principle to colour negative emulsions . The original silver image is replaced with dyes , to give an image free of the traditionally distinct grain . More importantly , it has latitude than normal silver - image films , and can tolerate massive under- and over - exposure . It needs to be processed in colour negative chemicals , however , or its own special developer .
AGFA DIA - DIRECT
With reversal processing , this slow ( ISO32 ) emulsion gives a projectable mono- chrome - transparency , intended for use in slide shows .
ABOVE Kodak's High Speed Infrared film has extended sensitivity beyond the longest visible wavelengths . With a 25 red filter , as here , scenes look more natural than if a visually opaque filter were lenses feature a red focusing mark on the barrel for use with infrared film .
LEFT When used with the appropriate high - contrast developer , Lith film produces a negative that has only two tones ; clear and black . The film can be used to print , for example , silhouettes . Varying exposure simply alters the relative proportions of black and white in the image .
FAR LEFT An image captured on Ilford XP - 1 , a chromogenic film related to colour negative emulsions XP - 1 can take massive under - and overexposure and still result in images with relatively fine grain . However , it needs to be processed in colour negative chemicals .
INFRARED
Kodak's High - Speed Infrared has extended sensitivity beyond the longest visi- ble wavelengths . When used with a visually opaque filter ( Wratten 87 or equi- valent ) , it can give startlingly unusual renditions . Certain surfaces and materials reflect infrared wavelengths quite differently from visible light , so that on this film they appear lighter or darker than expected . Healthy green vegetation , for example , is very bright , while blue sky is almost black . With a 25 red filter , or none at all , the visible wavelengths dominate , and the results look less unusual .
High - Speed Infrared film is not easy to use . It needs careful storage ( at low temperatures ) and protection from light to the extent that even the cassette should only be handled in darkness . Most lenses are not perfectly corrected for chromatic aberration , and focus infrared rays at a different point from ordin- ary light ; be careful to use the red focusing provided for this purpose on the barrels of most such lenses . The emulsion also has a very coarse grain .
LITH FILMS
These are , strictly speaking , not designed for normal camera use , but can give interesting and dramatic results if you do . They are intended for various kinds of special darkroom procedure ; used with the appropriate high - contrast devel- oper , they produce a negative that has only two tones : clear and black . This film can be used for slide projection ( the best way of making titles ) or printed to give , for example , perfect silhouettes . Varying the exposure simply alters the relative proportions of black and white in the photograph ; there are no inter- mediate tones .
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