jcb4718
Well-known
Could anyone give some insight into the reason for the aspect ratio of the Leica screw mount viewfinder and the SBOOI brightline finder? The SBOOI has a ratio of about 1:1.25 (24x36mm is of course 1:1.50) but for the near parallax 'dotted line' this reduces to about 1:1.50. So I'm tempted to imagine that when focussed on infinity there is an invisible 'dotted line' at the bottom in order to have the 1:1.50 film aspect for both near and far. If this is so, why was a 'dotted line' not included at the bottom? My IIIf viewfinder also has an aspect ratio of about 1.25 so you might imagine there should be two 'dotted lines' (top and bottom)so both near and far have the 1:1.50 aspect ratio. However, vertically, the viewfinder is pretty close to the lens centre (much closer than the SBOOI) so you would expect a much smaller parallax correction i.e. you would expect in any case the viewfinder to have an aspect ratio closer to 1:1.50. Can anybody offer any insights? Also how do folks use their SBOOI and in-camera viewfinder, in particular near vs. far?