Re: Belplasca Marries Supermodel?

[bercov@xxxxxxxxxx (John Bercovitz)]

I don't know if the Belplasca is magic or not.  It's price is certainly
magic but its performance does not exceed limits placed on lenses by
physics.  I've done some resolution tests with lens charts and found
how many line pairs per mm various lenses will do with ordinary films.
Let me hasten to say that I don't think too much of this sort of test
but at least I can do it and I can't do MTF curves with the simple
equipment I have.  So here are a few tests and you can decide for
yourself.
John B

Belplasca res test       April 1994
Film: Kodachrome ASA 25
 
                            radial              circumferential
f/stop  lpmm in the center  lpmm in the corner  lpmm in the corner
 
4          48                   54                  38
5.6        61                   54                  54
8          61                   61                  61
11         61                   61                  54
16         48                   48                  48
 



FED res test       Sept '93
Film: Kodachrome ASA 25

f/stop      lpmm in the center   lpmm in the corner
 
5.6               72                 36
8                 64                 45
11                64                 40
16                72                 40

(tangential and sagittal approx equal)




Kodak res test       April 1994
Film: Kodachrome ASA 25
 
        radial              circumferential
f/stop  lpmm in the center  lpmm in the corner  lpmm in the corner
 
5.6       60                  --                        --
8         68                  24                        24
16        60                  38                        21

(tangential and sagittal approx equal)




Canon lenses  Nov 93
Film: Kodachrome ASA 25

ATE1 V1
ATDT *70,4266610
 


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