In a truly vertical photograph 6 of fig. i is zero, hence the principal axis pSP is vertical and coincides with the plumb line, n and p are therefore ... It has also been shown that tilt displacement is radial from the isocentre i. ... Skill in the use of the needle must be developed by anyone wishing to do serious photogrammetric work. ... The tendency is to make needle pricks which, to scale, are of astounding size.
|Title||:||handbook of aerial mapping and photogrammertry|
|Publisher||:||CUP Archive -|