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jnantz
28-Jan-2002, 01:27
hi - sorry for asking this question but can anyone tell me the difference between a "regular" 75mm lens and a 75mm lens that is an "oscilloscope lens"? is the latter only used for macro type work with a specific kind of camera? or can it also be used as a regular olde 75mm lens on a 4x5 camera? thanks in advance for your help! john

Thomas Vaehrmann
28-Jan-2002, 03:32
Hi John,

the main differences are image-circle and speed: an 75mm oszillo-lens will not cover 4x4'', it was mostly designed for 1:1 ratio on polaroid. And because the signal on the oscillo-screen was dim and fast, the lenses offered large f-stops. I read about that they were, in this specific circumstances, pretty good, but mine (early post- WW II) is realy bad. So if you can pick up one cheap, you can try it for macro, if the image-circle will be large enough, and have a spare shutter if you don't like the results.

Neal Shields
28-Jan-2002, 21:19
I have played with several. If there is a way to get them to cover 4X5 at infinity, I can't figure it out. I have even reversed them. I haven't gotten around to using them for macro yet but just playing around it seems that they may work well for that.

Neal

jnantz
29-Jan-2002, 22:14
thanks for your responses ..! - john