Steinheil wide angle adapters

["allan carrano" <allan.carrano@xxxxxxxxxxxxx>]

     Over a month ago there were comments on the list about Steinheil 
     adapters being detrimental to image quality. 
     
     I've been using my Steinheils for 2-3 years now with excellent results 
     and was perplexed by the remarks concerning their poor performance.  I 
     knew my use of the adapter results in stereo slides that are 
     undetectably similar to those taken without the adapter (except, 
     naturally, for the wider angle of view).  So, in the time from that 
     discussion on the list until the present, I've conducted some tests to 
     explain why the differing opinions.
     
     I used two Steinheil adapters on four Stereo Realist cameras in my 
     investigations.  I ran experiments to check that focusing variances 
     between cameras were accounted for, and that the rear elements of the 
     Steinheils were the same distance from the front elements of the 
     camera lenses (I was prepared to do some shimming to eliminate this 
     possible variable, but found there was no need to do so.).
     
     I shot four rolls of 36 exposure slide film (even switching the same 
     roll between cameras to eliminate whatever film variable might exist, 
     though I don't really know what that might be).  I shot flash 
     exposures of the same cluttered area of my living room, from f/11 to 
     wide open (f/2.8 or f/3.5 depending on the camera).
     
     My findings were that both Steinheils gave the same results. 
     Therefore, unless I was just lucky and used "good" Steinheils instead 
     of "bad" ones, the difference of opinions, alluded to above, is not 
     due to quality differences in adapters, at least in not my tests.
     
     My major discovery was that the 2.8 Realists differed from the 3.5 
     Realists with regard to image quality with the Steinheils in place.  I 
     would like to comment first that although I've heard/read that the 2.8 
     Realists have better lenses than the 3.5's, I've never been able to 
     convince myself of that fact by looking at slides in my red button 
     viewer.  Now with Steinheils attached, I do see the difference.  The 
     2.8 Realists with the adapters produced slides that were sharp as long 
     as the f stop was above 5.6.  Even f/5.6 was not terrible.  But below 
     f/5.6 the "fuzzies" really were evident.  The 3.5 Realists with the 
     adapters produced "fuzzy" results at f/11 that were comparatively 
     equivalent to the 2.8 Realists results at f/4 - f/5.6.
     
     Since I shoot almost exclusively at f/8 to f/16 with Steinheils on my 
     2.8 Realist, I now understand how my opinion of their performance can 
     differ with someone using them on a 3.5 Realist. 
     
     Conclusion:  Steinheil wide angle adapters are more than a toy         
                  with 2.8 Realists.  And anyone who uses a 3.5 Realist     
                  with these adapters and is dissatisfied with results,     
                  I'll be happy to take them off your hands, and won't even 
                  charge you for my trouble. :-)  
        
     
          
     
      


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