own calibration) 
- time ínterval of at least 15 seconds between the different exposures has been applied 
- sensitometer used: EG&G Mk VII 
3.2 Development 
The Pakotone AVI has a processing width of 61 centimeter and therefore aerial film can be processed 
starting at three different positions: "left", “centre”, right”. 
-prior to the final testing machine speeds have been determined in order to reach the characteristic 
gamma for various film types (see below) 
- replenishment has been adjusted such that 300 milliliter per of fresh developer per square meter 
and 50o milliliter of fixer was pumped in 
Table 1 : Film type, machine speed, resulting gamma 
FILM MACHINE SPEED (inch per minute) GAMMA 
AVIPHOT PAN 200 40 1.4 
AVIPHOT PAN 150 30 1.8 
F P 3 Aerial 25 1.0 
H P 5 Aerial 28 1.0 
PLUS X 2402 25 1.5 (film for checking sensitometer and chemistry) 
DOUBLE X 2405 30 1.1 
Table 2 : Scheme of development 
ORDER SAMPLE IN-PUT POSITION 
1. test strip for checking chemistry centre 
2. first 10.4 meter test film centre 
3. second 10.4 meter test film left 
á. third 10.4 meter test film right 
5. fourth 10.4 meter test film centre 
6. fifth 10.4 meter test film right 
7. sixth 10.4 meter test film left 
8. seventh 10.4 meter test film centre 
9, three sensitometric control strips centre (for checking the chemistry at the same time) 
Remarks on development: 
-all control strips (for checking sensitomtry and chemistry) have been developed with the same 
machine speed 
- when the development of the seven test films of 10.4 meter length each (after one to three weeks) 
was repeated, the same machine speed has been applied as in the first development 
3.3 Densitometry 
- the densities were measured with a calibrated densitometer; calibration was done repeatedly 
- average densities were determined of the step tablets on the control strips respectively of the 
double step tablets on the test films (10.4 m) 
- all densities were measured with an aperture of 3 mm (diameter) of the same densitometer - 
GRETAG D 300 
3.4 Evaluation 
- Gradation and speed point have been determined by the straight line which fitted best; that gra- 
dation in in fact the average gradient G between the point on the curve with the density of 0.4 
above base plus fog and the point at which the exposure was 10 times higher (i.e. 1.0 log units 
to the right) 
- for tests carried out here the exposure leading to the density of 0.4-above base plus fog 
determines the speed or general sensitivity of the films 
- mximum density is defined as density on the test film which was exposed. through the step tablet 
density 0.05 (for level of the step tablet and lowest density) 
- the general sensitivity - rel. DIN (relative because of the speed point 0.4 above base plus fog 
instead of 0.1) - was calculated according to 
1 
  
rel.DIN - 
where (E*t) bs is the quantity of light leading to the density 0.4 above base 
plus fog (E*t) | 
- the exposure eS esctively the quantity of light is known from the EG&G sensitometer ; with the 
neutral density filter applied (D - 3.65) the exposure equivalent to illumination times time is 
(Est) ie = 424347 63-65 + log grel(E*t) 5 
4. Results 
4.1 Sensitometric exposures 
- fluctuations of the sensitometer have been determined prior to exposures of the test films; 
the - 3% indicated by the manufacturer (4242.7 I 3% luxseconds) have even not been reached ; 
the actual deviations were about = 2% 
- results of the evaluation of three sensitomtric strips have shown the same fluctuations, 
therefore: the average values of speed point and gamma were acceptable; 
sensitometric data can be used for checking the chemistry after processing the test films 
  
4.2 Control of chemistry 
- see figure 2 
remark: Increase of gamma, sensitivity and maximum density at the 4lst day was caused by a malfunction 
in the replenishment system; at the 39th day 4 to 5 liter of fresh developer were flowing into the 
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