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Additional Pacemaker Speed Graphic information is available at www.graflex.org

I use the film box speed with all my cameras including a 4"x5" Pacemaker Speed Graphic and 4"x5" Graflex Model D. The latitude of black & white and color print film is so great that if your light meter and shutters are reasonably accurate, and good light metering techniques are used, the box speed works quite well. I have never found that film testing showed enough deviation to make any change necessary.