Operating Manual

7
Stopbath
Fixing
Final wash
Drying in the drying cabinet
Roller dryers
10.3 Recommendations for the darkroom 90
10.4 Silver recovery 90
10.5 Automatic film processing 91
NDT-U (universal) film processor
NDT-E (economy) film processor
10.6 Checking the developing process and film archiving properties 93
PMC-strips to check the developing process
Thiosulphate-test to check the film archival properties
10.7 Storage of exposed films 95
11. Defect discernibility and image quality 97
11.1 Unsharpness 97
Geometric unsharpness
Inherent (film) unsharpness
Total unsharpness
11.2 Selection source-to-film distance 101
11.3 Other considerations with regard to the source-to-film distance 102
Inverse square law
Selection of radiation energy (kV)
Selection of gamma source
11.4 Radiation hardness and film contrast 104
11.5 Summary of factors that influence the image quality 105
12. Defect orientation, image distortion and useful film length 107
12.1 Defect detectability and image distortion 107
12.2 Useful film length 108
13. Image quality 111
13.1 Factors influencing image quality 111
13.2 Image quality indicators (IQI) 112
Wire type IQI according to EN 462-1
13.3 List of common IQI’s 114
ASTM IQI’s
AFNOR IQI’s
Duplex IQI’s
13.4 Position of the IQI 117
13.5 IQI sensitivity values 117
14. Film exposure and handling errors 119
6
Gradient of the density curve
Average gradient
Effect of developing conditions on the density curve
7.5 Film speed (sensitivity) 65
7.6 Graininess 65
8. Film types and storage of films 67
8.1 The Agfa assortment of film types 67
8.2 Film type selection 70
8.3 Film sizes 70
8.4 Handling and storage of unexposed films 70
9. Exposure chart 73
9.1 Exposure chart parameters 73
Type of X-ray equipment
The radioactive source
Source-to-film distance
Intensifying screens
Type of film
Density
Developing process
9.2 Densitometer 75
9.3 Producing an exposure chart for X-rays 75
9.4 The exposure chart 78
9.5 Use of the exposure chart 78
9.6 Relative exposure factors 80
9.7 Absolute exposure times 80
9.8 Use of the characteristic (density) curve with an exposure chart 81
10. Processing and storage of X-ray films 85
10.1 The darkroom 85
Entrance and colour
Darkroom lighting
Darkroom layout
Tanks
10.2 Chemicals and film-development 86
Making-up processing solutions
Developer
Fixer
Developing time and bath temperatures
Film agitation
Replenishing