Maco ORT 25's emulsion is a thincoat emulsion that is 7 microns without base using traditional crystal technology and is relatively high contrast.
Since an industry standard for determining speed of orthochromatic film has not defined, no definitive information about a standard value can be given.
As a starting point for ORT 25, begin with an exposure setting of ISO 50 based on incident light measurement, light meter pointed from object to camera. Make individual test for determining optimum exposure.
Granularity and Resolving Power for ORT 25 is:
RMS (x1000): 6.0. Contrast 1000:1 350 lines/mm.
ORT 25 is a high contrast film, excellent for copy work and forensic photography. For portrait and studio work use an orange filter. Because of its high resolution, this film produces extremely sharp, grainless negatives.
Both ORT 25 is available in 35mm, 120, 4x5 sizes.
