Its an obsolete objective that was designed for early semiconductor "printing" and microfilm capture (many of these have been salvaged from junked microfilm systems). Within the optical band they were designed for they were 30-40 years ago about the best that money could buy (but not the only "game" in town). They were, however, NEVER designed for use with pictorial photographic papers as an "enlarging lens". With multigrade/variograde papers they have poorer performance then pedestrian Componon and Rodagons (which can just be, unlike the S-Orthoplanar, just "screwed" into an enlarger given their standard threads and housing). Its moot, however, since with your example of 5x7" prints it'll be hard to really judge the difference, beyond maybe contrast, between any of these and a "coke bottle". Most multigrade papers have resolutions hardly above 50 lp/mm and most of our photographic capture systems (film, objective etc.) won't get beyond (even using highest resolution microfilms at pictorial contrast with the absolete best optics) 80-100 lp/mm. The main kick of the S-Orthoplanar is the hype in places like Zeiss' Camera Lens News (which, as I've widely commented, is at times hardly above the scientific and journalistic standards of the National Enquirer) and other references where it gets used to break physical and optical laws.