Phytec FireWire-CAM-001, Manual

Page: 34 / 86

FireWire-CAM-001 / 002
28 
PHYTEC Meßtechnik GmbH 2005 L-661e_1
The C/CS-Mount ring influences the so-called „flange focal distance“.
This is the distance between the back of the lens and (the part that is
attached to the camera) and the picture plane– in our case the surface
of the CCD sensor. The pictures shown in Figure 21 illustrate the
difference.
Figure 22: Flange Back Distances and Mountig of C-Mount (Top) / CS-Mount
(Bottom) Lenses
In reality the mechanics of the lens and the cameras can vary slightly
from one model to another, which may also influence the flange focal
distance. If, for example, you are not able to set your lens to „infinite
focus“, this is a typical sign of an incorrect flange focal distance.