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Message: <blockquote data-quote="Paul Corfield" data-source="post: 3207162" data-attributes="member: 19132">Did some tests with 3 of my better magnifying optics. Tried to edit in Photoshop but CS6 doesn't let you open images of bank notes. Had to do very basic editing/saving in Microsoft paint. On a £10 note I use the eyes as the ultimate test. Looking at the bank note with the human eye you can't even distinguish the very fine lines that make up the eye. It's probably even finer than feather detail making it a very good test of resolving power.Lenses used were the new medium format 6X7 2X Vivitar TC that I got the other day, 2X Teleplus macro focusing TC and a TN from a Vivitar 100-200mm close focusing lens. Serial number on the lens starts with 28 showing it has high quality Komine made glass. Power is higher at around 2.5X. Mounting it as close to the camera as possible shows some softness in the corners. Spacing it away from the camera by about 15mm is enough to get rid of the soft corners but magnification is increased to around 3X or more making it quite powerful for normal use. Sharpness is excellent from the Komine glass and is the best of these three tests. I shall explore other Komine made lenses to see if I can turn up a lower powered gem. All three tests are very sharp overall. The two TC's were sharp to the corners. The 6X7 2X TC gives around 1.7X on my Nikon body which is much smaller than the medium format body that its intended for. Paul.</blockquote>