The orthogonal photography aims at the restitution in the
tridimensional space of the position and the attitude of a physical
In our particular application of the orthogonal photo-graphy, the
object is a small caliber projectile in flight and each station
realises the orthogonal shadowphotography of the projectile in true
Using several mutually aligned stations along the trajectory, the
position of the center of gravity as well as the attitude in space
of the projectile can be restituted. Using this information the
spatial angle of attack and its rate of variation can be deduced.
In comparison with the photography based on reflexion, the
shadowphotography has the advantage that some characteristics of
the supersonic flow around the projectile are visualised.
Eduard A. Celens,
"Orthogonal shadowgraphic nanolite stations", Proc. SPIE 1358, 19th Intl Congress on High-Speed Photography and Photonics, (1 April 1991); doi: 10.1117/12.24059; https://doi.org/10.1117/12.24059