Kodak P-255 manual Spectral Sensitivity, Storage and Handling, Exposure, Filter Factors

SPECTRAL SENSITIVITY

Technical Pan Film has reasonably uniform spectral sensitivity at all visible wavelengths out to 690 nanometres (nm). Because of this extended red sensitivity, red areas and flesh tones may appear lighter than they would with conventional black-and-white films. This is often an advantage. For example, it helps conceal some skin blemishes and often adds a pleasing luminous quality to skin tones. (This effect is less evident in portraits made in the shade outdoors, because there is less red light present.)

To approximate the response of conventional panchromatic films more closely, make exposures through a color-compensating filter such as a KODAK Color Compensating Filter CC40C or CC50C (cyan). With this filter, no exposure compensation is necessary; however, there may be a slight loss in sharpness.

STORAGE AND HANDLING

High temperatures or high humidity may produce unwanted quality changes. Store unexposed film at 75°F (24°C) or lower in the original package. Always store film (exposed or unexposed) in a cool, dry place. For best results, process film as soon as possible after exposure.

Load and unload roll-film cameras in subdued light, and rewind the film completely before unloading the camera. Total darkness is required when you remove film from the magazine or load and unload film holders.

Protect processed film from strong light, and store it in a cool dry place. For more information on storing negatives, see KODAK Publication No. E-30, Storage and Care of Photographic Materials—Before and After Processing.

EXPOSURE

The speed of this film depends on the application, the type and degree of development, and the level of contrast required. Therefore, no single speed value applies for all situations. (Speed ratings may range from a low of EI 16 for pictorial photography to a high EI 320 for microfilming. Use the exposure indexes in the following table with meters marked for ISO, ASA, or DIN speeds or exposure indexes. They are intended for trial exposures.

You can expose this film with daylight or tungsten light. Exposure to tungsten illumination produces a 10-percent increase in speed and a 5-percent increase in contrast.

Exposure- and Contrast-Index Values for Various Development Conditions

Contrast			KODAK	Development
				Time	Exposure
	Index		Developer	(minutes at	Index
				68°F [20°C])
High		2.50	DEKTOL	3	200
2.40 to 2.70			D-19 (1:2)	4 to 7	100 to 160
2.25 to 2.55			D-19	2 to 8	100 to 200
1.20 to 2.10			HC-110 (Dil B)	4 to 12	100 to 250
1.25 to 1.75			HC-110 (Dil D)	4 to 8	80 to 125
1.10 to 2.10			D-76	6 to 12	64 to 125
1.00 to 1.50			MICRODOL-X	8 to 12	32 to 50
0.80 to 0.95			HC-110 (Dil F)	6 to 12	32 to 64
Low		0.50 to	TECHNIDOL	5 to 11	16 to 25
		0.70	Liquid

For pictorial applications, use EI 25/15° and process the film in KODAK TECHNIDOL Liquid Developer. (Refer to “PROCESSING.”)

For high-contrast reversal-processing applications, use EI 64/19° to produce slides from high-contrast subjects such as line art. Process the film with the KODAK PROFESSIONAL T-MAX 100 Direct Positive Film Developing Outfit.

Filter Factors

Multiply the normal exposure by the filter factor indicated below. If you use a through-the-lens meter, take the meter reading without the filter over the lens, and then calculate your exposure by using the filter factor. Where no filter factor is listed in the table, no test was made with that filter.

KODAK WRATTEN		Tungsten	Daylight
	Gelatin Filter	Filter Factor*	Filter Factor†
No.8 (yellow)		1.2	1.5
No. 11 (yellowish green)		5	—
No. 12 (deep yellow)		1.2	—
No. 15	(deep yellow)	1.2	2
No. 25	(red)	2	3
No. 47	(blue)	25	12
No. 58	(green)	12	—

*Based on a 1-second exposure and development in KODAK HC-110 Developer (Dilution D) for 8 minutes at 68°F (20°C).

†Based on a 1/25-second exposure and development in KODAK TECHNIDOL Liquid Developer for 9 minutes at 68°F (20°C).

2 KODAK PROFESSIONAL Technical Pan Film • P-255