Mechanical Adjustments; Flange To Focal Plane Distance (Ffd) Adjustment - Canon EOS 5D Service Manual

2．MECHANICAL ADJUSTMENTS

2.1 Flange to Focal Plane Distance (FFD) Adjustment

・Adjustment procedure is same as the EOS-1D series.
・ FFD adjustment is required when replacing the Front Panel (Mirror Box)
CAUTION
Ass'y or the mount.
・ It is also required when tilted images occur due to impact caused by
dropping, etc.
<Purpose>
FFD implies the distance between a reference plane of the lens mount and the CMOS sensor
plane. It cannot be measured at service; therefore, measure the distance from the mount
plane to CMOS mounting washer plane (washer included) to adjust FFD to be within the spec.
<Service Parts>
Front panel unit: Compensation washers are not attached as before.
IMG unit: Offset values based on the specification are written.
<Specifications>
Front panel unit replacement: Set the distance from the lens mount to the image unit
IMG unit:
Reference)
FFD: The dimension from the lens mount surface to the FFD (Flange to imaging plane) is
44.00 +/- 0.02mm.
<Tools>
・Digital micrometer (Commercially available)
・Mount Fastening Tool (CY9-1547-000)
installation surface to the same distance as before front panel
unit replacement.
Add or subtract the IMG unit compensation amount to/from
the difference calculated by subtracting the original distance
between the lens mount and the image unit installation
surface (washer included) from the specified distance. Select a
washer that meets calculated value to make FFD be within the
specification.
3
Adjustments