How Your Film Is Finished At The Lab

For Class #11

 Instructor: Norman Hollyn T.A.: Beth Moody
 Office: 310-821-2792 Phone: 323-472-1164

 E-Mail: nhollyn [at]

E-Mail: elizabethmoody [at]

Note: Each of the links below, opens up a picture in a new window. Simply click on its close box in order to return to this page.

The process of taking the film negative and creating a positive print with a soundtrack attached (the so-called "married answer print") is fairly straightforward, though many editors aren't even aware of its details.

Now, all will be revealed to you, courtesy of Kodak and the CFI web site pictures.

This figure shows how a print is made from a negative. The negative (the bottom orangey film strip) is rolled and placed in contact with some color print film (the top red strip) on a copying sprocket wheel with a small hole in it. When light is shone through the hole, it exposes the print and a copy of that frame is made.

The relative amounts of the three colors that make up the typical color film (Yellow, Cyan and Magenta or Red, Green, and Blue) are determined by the color timer, who programs the lab printer. The three colors are separated using a prism (as shown in this diagram) and each one is sent to its own filter. The relative amount of each color (as determined on a scale from 0 to 40 -- called "points") is controlled by the three light valves and the three light streams are then combined again before the properly timed light is sent through the exposure slit and onto the color print film. An optical printer is shown in this photo. We learned about opticals way back in this lesson.

This chart shows all of the steps that a 35mm negative goes through in order to produce a print for distribution in the theatres.

This figure shows how the negative is combined with the optical soundtrack negative to provide a positive print with picture and sound married together in a way that is necessary for projection (double system is not used in most theatres in the country except as noted below).

However, the picture at the right in the figure above, shows the old configuration when there was only one optical track to worry about. However, things are much more complex today as this figure shows. All sorts of stereo configurations are now possible and, in fact, necessary. This figure shows the location of each of them. SDDS placement is shown in this chart. DTS stereo is triggered by a time code, which links the film to a separate CD.


Thanks to Kodak and CFI Laboratory for the use of their pictures.

Though I've tried to accomodate other browsers THIS SITE IS DESIGNED FOR BEST USE WITH IE for the PC, SAFARI for the Mac, and FIREFOX for both the PC and the Mac. It also looks reasonably good on the iPhone. Lucked out on that!

All material, except where noted, ©1999-2008 by Norman Hollyn. Questions? Comments? Suggestions? Send me an e-mail at my office
Last Modified - September 30, 2008