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Eastman Ectachrome commercial film (16 mm):

EASTMAN EKTACHROME COMMERCIAL FILM

TYPE 7255 (16MM)

This film was prepared for shooting with the camera, so that after exposure it leads to color reversal images of low contrast, so that they can be sold on other films, so we obtain the required release prints for display and circulation. In order to obtain this copy, we may use one of the two pipes:

(A) Of course, on color reversal films such as: - Eastman Reversal color print film type 5269 (16 MM). (b) Blowing or of course on Internegative Eastman color Internegative Film Types 5270 (25 MM.) J or (16) 270 type, then this intermediate color film was printed on another such as Eastman color print film, types 7382 ( 16 mm.) 15382 (35 mm.)

It is thus obtained in the end in color copies printed or enlarged. This is due to the lack of contrast in the images recorded on this reversal film. Eastman. (7255) Ektachrome commercial, so it is no longer a basis for displaying itself on the projector, but rather for the original to be used to obtain copies prepared for display. Perhaps the wisdom of producing it to be low in contrast is a clear wisdom, as it is known that the degree of contrast increases slightly when printing or enlarging, so the contrast of the original must be reduced in order for the degree of contrast of the Release Prints to reach an acceptable level that is equal in quality to the pictures. The reversals that you get directly from other reversal color films intended for direct viewing (such as Kodachrome film Daylight & Type A)

Sensitivity Speed: Identification Marks: A latent image read after displaying Ektachrome Safety film and next to it there are numbers denoting the lengths in feet (Footage 11 ASA) when filming in daylight with an 85 .A filter. S. Kodak ratten NO while photographing under a tungsten lamp with a color temperature of 3200 Kelvin.

The color temperature of the rays for which the film was prepared: This film was prepared for shooting under Tongen lamps

Its color temperature is 3200 Kelvin. If other light sources are used, appropriate filters must be used to adjust the color temperature. In the following table, an indication of the necessary light filters when using other light sources. .Light Balancing Filters

light source

The filter to be placed in front of the light source

The filter to be placed in front of the lens

Two tungsten lamps 3200 Kelvin

No filters are required in this case

Photoflood lamps

nothing

Wratten No. 81

Two lamps: 3350 Kelvin

nothing

Wratten No. 81

An electric carbon arc that emits large light energy (150 amperes). 150 amps.

Wratten No. 85

Brigham Y-1

Duarc. 40 Amps.

Florentine glass

Wratten No. 85

Daylight (a mixture of sunlight + skylight).

nothing

Wratten No. 85

In addition to the remaining two filters, it is very often necessary to use a set of other color-correcting filters known as color compensating filters (which we have already mentioned on page 81) during the stages of printing the original copy on other films intended for reversal color print. film or when making a color internegative negative film. The use of these filters would compensate for the difference in spectral sensitivity between a group of printing films that differ in the production of their emulsion No, and this is something that would require each group of printing films to correct colors differently from what is required by another group.


In the following table, we show the diameter of the diaphragm openings that are suitable for the amount of incident light, when using the previous film for imaging in artificial light emitted by tungsten lamps. This is assuming that the speed of the cinematographic camera is 24 frames per second, i.e. the exposure speed = exposure speed of approximately one second.

Diaphragm slot.F NO

See

the amount of incident light. In feet candles