TM 5-6675-319-14
CAUTION
• When moving film, place pressure plate lift knob to the left. This raises
pressure plate and prevents scratching film on pressure plate or stage
grid during movement.
• Easel is coated with acid-resistant enamel and planed to an exact tolerance.
Use of sharp objects in proximity to this surface will damage it. When
using magnetic paperweights, be careful in placing them on easel.
P r o t e c t i ve
covering should be placed over this surface when rectifier is not in use.
NOTE
• There are three methods commonly used to rectify an aerial negative:
C o n t r o l t e m p l a t e o n e a s e l i n c o n j u n c t i o n w i t h a e r i a l n e g a t i v e i n r e c t i f i e r.
Control points are sometimes difficult to identify due to extraneous
d e t a i l i n i m a g e.
Two-Template Method:
Control template on easel in conjunction with transpar -
e n t o v e r l a y o f a e r i a l n e g a t i v e i n r e c t i f i e r.
This method is easier than the
above method because extraneous detail is eliminated on transparent overlay.
Computed Data Method:
R e q u i r e s t h a t a m o u n t o f t i l t a n d i t s d i r e c t i o n in
aerial photograph be known, as well as focal length of aerial camera, focal
l e n g t h o f r e c t i f i e r l e n s a n d m a g n i f i c a t i o n r a t i o . T h e s e v a l u e s a r e s u b s t i-
t u t e d i n t o e q u a t i o n s w h i c h d e t e r m i n e s e t t i n g s f o r m a g n i f i c a t i o n t i l t , s w i n g,
X-and Y-drive settings.
This method is simpler since it requires only setting
movement scales to computed values.
• If film or dry paper is to be used, proceed to step h.
f. Place wet photosensitive paper, emulsion side up, on easel. Use squeegee
roller to make uniform contact between easel and paper.
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