Originally posted by bobspez Wouldn't reversing the lens make it even more of a macro? Right now with the 4x increased distance to the sensor the total field of view that can be focused is smaller than a tennis ball. The lens is manual, no auto settings.
No, it just means that the lens, which was probably designed to work best at around infinity, gives better results reversed. Most normal lenses are designed to give their best results at infinity, or near it. Dedicated macro lenses, like the Olympus 50/3.5 are designed to work best at 1:10, for example. Others might work best at 1:1, or if they have floating elements, can perform better over a wider range vs. non floating element counterparts. 10x microscope or specialized lenses like the Olympus 20/2 auto macro perform best at 10:1 for example. No need to reverse those. Even the Pentax Auto Bellows 100/4 macro is recommended to be reversed for greater than 1x magnification. That's also the reason there's a P645/M58 reverse macro adapter set, where you can use the 55/2.8 reversed, for example, which gets more useful with the addition of macro rings, helicoid and/or bellows. Also, you can use wide angle lenses like the 28/3.5 super-Takumar for greater magnification, which also happens to have an M58 filter ring, but the smaller mirror box makes their working distances shorter.
Originally posted by bobspez My lens has the Leica M39 mount, but it is a Canon lens. Maybe the M45 lens is a M45 mount? I didn't see the ebay posting for $100 but did see some in the $800 range.
I think there must be a confusion somewhere. Either it was a typo, e.g. m645 (Mamiya)? There's L39(LTM), M39 and M49, but no M45. There's a Leica M4 camera…
Last edited by torashi; 12-19-2019 at 10:39 AM.