Canon T2000 - Manual (Page 22)

Framing knob (3)
When you start projecting,
it may happen that the
separating line betweeen
frames becomes visible on
the screen. This can easily
be corrected by turning the
framing knob. When the
frame line has been set, it
does not normally require
readjustment during pro­
jection.
Focusing knob (4)
The extra-large focusing
knob makes focusing par­
ticularly easy and smooth
- a point of major impor­
tance in the projection of
Super-8 or Single-8 film
where even very slight
axial shifting of the lens
will result in a noticeable
change in focus on the
screen.