LEICa R 1:1 macro

greenspun.com : LUSENET : Camera Equipment : One Thread

Could someone please tell me the easiest way to get a 1:1 image with a Leica R. Would it be with an extension tube, or turning the lens back to front with an adapter ?

-- Anthony Brookes (gdz00@lineone.net), January 20, 2001

Answers

Anthony,

Regardless of the brand, the science is the same. To reach a 1 to 1 reproduction ratio on film, you need extension that is equal to the focal length. If you are using a 50mm lens, you need 50mm of extension... any combination of tubes, helicoil focusing treads or bellows. Extension is not much of a detriment optically, but you do lose light, which TTL metering will compensate for.

Optical methods of magnifying the image include close-up filters, converters and reversing of the lens. Converters and cheap close-up lenses will effect optical quality, requiring a small f-stop for adequate quality. Reversing works well with moderate speed lenses, but fast glass is rarely useful due to less of a flat field, which is really noticeable at high magnifications.

I use real macro lenses, but if I didn't have them, I'd opt for extension tubes, (which I also use for my macro and long lenses), and a medium speed optic like the 50mm Summicron or 90mm Elmarit. The tubes are cheap, since there is no glass, and sets of three that equals 50mm of extension are usually under a Hundred Dollars. As far a calculating... divide the extension into the focal length for the reproduction ratio. For example 50mm of extension on a 100mm lens gives half life size.

-- Al Smith (smith58@msn.com), January 20, 2001.


Moderation questions? read the FAQ