In cooperation between Commissions II and IV of the International Society 
of Photogrammetry a questionnaire was sent out to the national reporters 
of the Commissions from Sub- Commission IV :4. 
Answers were received from 38 organizations. Below a summary of the 
answers will be made, question by question. 
1.1 How is the aerial surveying camera checked and tested at the delivery? 
27 answers. 
Through laboratory tests. 
By the manufacturer only: 5 
By official institutes: 9 
In own laboratories: 4 
Through air tests. 
Complete model tests (planimetry and elevation): 12 
Elevation tests only: 3 
Official specifications exist in some countries. 
1.2 How is the surveying camera checked and tested during practical use? 
How frequently is the camera tested? 
25 answers. 
Through laboratory tests. 
By the manufacturer only: 3 
In own laboratories: 4 
Through air tests. 
Complete model tests (planimetry and elevation): 12 
Elevation tests only: 3 
Tests when needed: 3 
Tests regularly once a year: 8 
Tests regularly, more frequently than yearly: 13 
Tests before and after certain missions: 5 
Do you think that checks and specifications (tolerances) are necessary 
or suitable for the purposes which are listed below ? 
How should the checks and tolerances be constructed ? 
1.21 The flatness of the focal plane frame of the camera. 
1.22 The flatness of the locating back. 
1.23 The principal distance (camera constant or calibrated focal 
length) and the position of the principal point. 
1.24 The perspective quality of the lens (radial and tangential 
distortion, affinity, asymmetry). 
17 answers.