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Message:: [QUOTE="rmpsrpms, post: 1541656, member: 31773"]80mm is well within range to work with the Bausch and Lomb A-Stand, but 105mm requires enough additional working distance that you will need to compensate for larger coins (probably beyond Quarters) by removing the stage plate and setting the stand on a platform. An important point for would-be coin photographers: modern dedicated macro lenses shorten their focal length when focused for higher magnification. Most "100mm" lenses are actually ~60mm when focused at their closest distance to subject. This shortens the working distance compared with a "real" 100mm lens. Since most dedicated macros are very big in diameter, this severely limits illumination angles. This double-whammy is why I am not in favor of dedicated macros. To compensate for this, most folks "in the know" suggest longer macro lenses such as 150mm or 180mm. As these lenses shorten their focal length, they at least maintain enough working distance to allow flexibility in illumination angles. This focal length shortening is not a concern for duplication or enlarging lenses, as they don't change at all as you change magnification. Thus a 105mm enlarging lens like I linked to is equivalent to a ~180mm dedicated macro, and has very large working distance for larger coins (lower magnification). This can cause a problem if your stand is not tall enough.[/QUOTE]