Archived posting to the Leica Users Group, 2001/03/06

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: [Leica] Re: problem with my M6
From: leica@rakitzis.com
Date: Tue, 6 Mar 2001 08:43:49 -0800

I definitely see tighter frame spacing with my 15 Heliar.

I attribute it to the fact that the film gate is not perfectly flush
with the film -- since the 15mm will sit closer to the film plane than
any of my other lenses, it follows that the light rays reach the corners
of the film plane with a more extreme angle. So, they can "sneak" under
the film gate and make the image size larger than 24x36mm (or whatever
the actual film gate size is, I haven't measured it).

It's much easier to draw a diagram of this happening than to describe
it. Here's a lame ASCII version:


		        LENS
		       /   \
		      /     \
		     /	     \
		    /	      \
		   /	       \
		--/		\--		  GATE
		 /		 \
		/		  \
  ----------------------------------------------- FILM

Byron.