ORWO Color Positiv-Film PC 7
Table of Contents
PC 7 is a multilayer film consisting of three emulsion layers selectively sensitive to blue, green and red light. A yellow filter dye is embedded in the top layer to shield blue rays from the middle and bottom layers. A green antihalation layer is applied to the back of the film, which is removed during processing. In addition to the silver halides, each emulsion layer contains colorless dye formers which couple in the color developer to form image dyes. A partial color image then remains in each layer in the colors complementary to the sensitivity. A colored positive is obtained after complete processing in accordance with ORWO regulations. The ORWOCOLOR positive film PC 7 is shown schematically below.
Layer structure PC7
Format
70mm, 35mm, 32mm and 16mm
Identification no. 448— at 70mm and 35mm; 449— at 32 and 16mm.
identification
Light marking for all widths:
ORWO S (or ORWO SAFETY or ORWO SECURITY FILM)
sensitization
Panchromatic tuned to incandescent light.
darkroom light
The ORWO darkroom protective filter 166 in connection with a 15-watt lamp at a minimum distance of 100 cm or the ORWO darkroom protective filter 164 with a glow lamp (beehive glow lamp of type B 107) should be used as darkroom light. For indirect room lighting, we recommend the light of a sodium vapor lamp with the ORWO darkroom protective filter 165.
color copy
The ORWOCOLOR positive film PC 7 serves as a copy film for flat graduated negatives, with and without a mask. Its color balance is kept in such a way that the lowest possible copy filter values are required for copying mask negatives. The color copy can be made in the known way with filter strips containing gray filters and ORWOCOLOR control foils, or by additive filtering of the copying light. The gray filters and the control foils are supplied in the usual density gradations by VEB Filmfabrik Wolfen.
Tonkopie
When copying the tone from the tone negative onto ORWOCOLOR positive film PC 7, the ORWO blue filter 65 should be used. The sound track is redeveloped, it consists of silver and dye.
Recommended developers
ORWOCOLOR 11
processing sequence
Develop, soak briefly, stop hard fix, soak, bleach, soak, redevelop soundtrack, soak, fix, soak, dry.
Gradation
The ORWOCOLOR positive film PC 7 should be developed to a gradation of about 3.0. The gradation progression of the ORWOCOLOR positive film PC 7 is shown in the figure below.
Gradation Plot PC7
Source: ORWO cinema and television films III-18-177 Ag 004a/057/64 WP No. 202
