CONCLUSIONS/RECOMMENDATIONS 



It is obvious, from looking at the test prints, that the dome-ports do correct 

 for refraction-magnification. They also correct some of the pincushioning of 

 the flat-port (with the exception of the #7 dome, which had a very slight bar- 

 rel distortion effect) . Edge fall-off was more extreme in the flat-port com- 

 bination. Though there was edge fall-off to a minor extent in all the tests 

 except for the longer lenses and the 28mm Nikkor UW lens (which did have 

 refraction magnification) , we feel that further studies should be made to see 

 if it is possible to correct the slight pincushioning and barrel distortion of 

 the dome-ports. Contrary to previous theory, we found that the 50mm lens 

 seemed to have the same edge fall-off with both the flat-port and dome-port, 

 but one had the refraction magnification, the other did not. It is also obvi- 

 ous that the #7 combination gave the best edge sharpness on a comparison basis. 

 But the edge sharpness of the 3, 5, and 6 inch dome, utilizing the Plus-diopters, 

 was of such minor difference, in practical photography, the difference would 

 only show up in photogramic photography underwater . 



One of the largest problems of habitat UW photography is the problem of pressure 

 inside the habitat. If cameras are taken down, wet, they can be only opened in 

 the habitat if the housing has an air-intake valve. If a diver goes outside the 

 habitat with an UW camera at the habitat pressure, he risks the housing internal 

 air expanding, and bubbling out of the housing, and water coming in. What is 

 badly needed is a two-way, automatic pressure relief valve so that the camera 

 can regulate its own pressure. Early devices of this nature were used years ago 

 but there is a real need for an updated valve for further work of photography in 

 habitats. This problem becomes greater as the size of the housing increases and 

 reaches major problem proportions in 16mm and 35mm movie housings due to their 

 large size. 



We have found increased color saturation with the dome-ports, but since careful 

 comparison tests (such as the black and white test) could not be accomplished, 

 we cannot say to what degree the dome increases color saturation. 



The results of the automatic-exposure-control cameras (#1, 2, 3) were striking 

 because of the simple lenses of #1 and #2. Examples of photos taken with auto- 

 matic exposure control are shown in Figures 11 and 12. Further research should 

 be made into the advantages of automatic-exposure control cameras under natural 

 light, artificial, flash, and strobe conditions. 



VI -306 



