(granting there are no "absolutes") and the programs matching 
these values might then be selected as "most correct." A not too 
unsual perspective since optical designers have long been conversant 
with compromises. 
8.0 SUMMARY 
The quandrennuim for 1972 to 1976 has seen increasing use 
of OTF and MIF. In optical industries in Europe and Japan it 
is being used in quality control and evaluation of images. Many 
of the international studies have been connected with SIRA. 
Use in the United States and Canada is generally limited to high 
precision optics and analysis of space systems. 
Ihe United Kingdom is the only country with standards of 
testing which have been in use for some years. Investigations 
are now being conducted with the purpose of finding short-cuts 
in testing without serious restriction in data. 
West Germany and Japan are developing more comprehensive 
standards (parts of which are complete) and are conducting many 
studies, particularly into practical error analysis of equipment 
and techniques. 
French laboratories have assisted many studies, but their 
work on standards is not known (as of this writing). 
The United States is doing many scientific studies in error 
analysis of equipment and techniques and in microdensitometer- 
computer coupling, but only a few of the large manufacturers 
employ MIF in quality control. A standard for measuring MTF of 
emulsions is ready for publication and drafts for an OTF standard 
for optical devices have been written. 
There is activity in other nations as reported in previous 
sections. 
OTF/MIF equipment takes many forms, from the simple bench 
to the sensitive interferometer. More equipment is becoming 
automated with the goal of real-time data and go and no go solutions 
for designers, manufacturers, and users of lenses and optical 
equipment. 
OTF applied to evaluation of optical designs is now routine 
and there is some use in design of optics and optical instruments. 
OTF in image evaluation is now generally accepted as providing 
more information on imagery than resolution although resolution is 
still dependable and simpler to use and assess for many applications. 
As photogrammetrists, however, we need to be concerned with the 
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