The camera may also have obstructions which extend into the
normal overlap introducing an unwanted broad vignette. One baffle has been found to extend well
into the overlap area. The original filter retainer ring also tended to
severely vignette corners, evidenced in much of the Philadelphia shooting.
Curled or distorted vanes are common offenders.
An operation error which has occurred and must not be
permitted is neglecting to relocate the camera in lock position after racking
over to look through the individual camera view finders.
Not so evident perhaps is the glare reflected from vanes or
the back of the mirrors. This glare extends into the edges of the vignetted
area and often has considerable color. This particular trouble is difficult to recognize in a vignetted print,
although some kind of trouble is obviously present. Familiarity with the
appearances of the unvignetted print often indicates the source of
trouble. However, nothing can be done
to correct the trouble except that in the new printer an attempt can be
made to shift the feather as far as possible (limited to only a few thousandths
of an inch) away from the offending side to minimize the effect. This trouble
can be confused with the reflection of the sun or other bright object from the
side of the camera aperture close to the film. Rocket shots show these severe
In projection everything possible must be done to provide
absolute equality of screen brightness and color on each side of the
matchlines. The rest of the panels are unimportant relatively. It is the transfer from one panel to another
which is important. If the transfer is
perfectly accomplished, nothing further is required of the lights except to maintain
the condition, which the “shelf item” sources are not yet capable of doing.