FIGURE 13.
Lens assembly mounted in front focus
d. Move the locking handles on the carriages backward to release the
e. Rotate the front handwheel (clockwise or counterclockwise as
required) until the image on the ground focusing glass (figure 14) is
approximately the size desired.
NOTE:
The size of the image can be estimated by using the lines on
the ground focusing glass as a guide.
The distance between
the lines on the 8" x 10" focusing back is 1/2 inch.
The
distance between the lines on the 4" x 5" focusing back is 1/4
inch. The image dimensions can range from one-quarter to four
times the dimensions of the object being copied. Moving the
33