I just started using the Leica M-system again. I've had the camera for a while, but haven't taken it out on assignment until last week and I've noticed something that baffles me only because it makes no sense in the usual photographic world. The camera seems to gather more light than my Canon EOS system does. Using Fuji Press 800 film, 28mm lens and available light, the Leica just seems to show more shadow detail and doesn't wash out the highlights like the Canon does. Is this magic or something to do with the way rangefinder lens are manufactured and their relationship to the film plane. By the way, the lens is a Voigt 28/1.9. Maybe some non-voodoo types out there have an answer. P.S. It reminds me of the digital television images I see on the local stations when I have covered the same event they did, but the scene seemed much darker than what the

-- Dayton P. Strickland (daytonst@bellsouth.net), February 08, 2002

Answers

Stated simply, I think you have discovered (or discerned) the magic of Leica glass. I don't know that I'd say Leica gathers more light than others, but IMO there is a broader range of tonality present in Leica images.

:-),

-- Jack Flesher (jbflesher@msn.com), February 08, 2002.

Your experience may be the result of the microscopic pyramids that coat the inside of the M6, preserving the detail in the light as it passes through the air between the lens and the film. ;-)

Or, it might be that your Voigtlander 28mm (and most Leica lenses) are less prone to detail-robbing flare than many other lenses. Or, it might be a difference in how you are metering the scene, resulting in better exposures. Or, perhaps some combination of the above (excluding the mythical pyramids, of course).

There is no voodoo in the amount of light any lens collects (a given focal length and aperture will all be the same), but there is a certain amount of voodoo to lens design and what the lens does to the light passing through it. Zeiss lenses on other cameras employ similar voodoo in other formats.

-- Ralph Barker (rbarker@pacbell.net), February 08, 2002.

Dayton: you didn't mention which Canon lenses you're comparing to, but if you're using zooms they have a lot more glass elements (NOT pyramids!) 8^). Each air/glass and glass/glass interface reflects and refracts light instead of passing it on to the film as image.

Prime lenses have fewer elements, on average, than zooms, and rangefinder lenses often have fewer than SLR primes (e.g. the Elmarit 90 has four pieces of glass vs. five-six for Nikon's 85-105 lenses, and maybe 9-12+ pieces in a 28-105 or 80-200 SLR zoom).

Leica makes a big deal out of keeping the number of elements down in their designs (one reason why they are emphasizing aspheric surfaces in their newest designs - each ASPH surface does the work of two normal surfaces in terms of making optical corrections, and with half the light loss to reflections.)

-- Andy Piper (apidens@denver.infi.net), February 09, 2002.

I think you have discovered (or discerned) the magic of Leica glass

Er... in this case it should be the magic of Voigtlander glass.

-- Richard (rvle@yahoo.com), February 09, 2002.

Thanks for all the insight. After posting this I dug through some old magazines and came across an article in the September 2000 issue of Popular Photography that might shed some light on this. In talking about how rangefinders are better in many aspects over an SLR, Herbert Keppler talks about the distance from the rear of the lens to the film plane. An SLR must add extra distance for the mirror to clear, in some cases as much as 20mm's more. That same issue also has a review of the Hexar RF so his piece might have been a little slanted toward rangefinders, but everything he says makes sense. As for more info on this, my Canon lens is a 2.8 zoom and the light readings from both cameras were identical. By the way, if your work, like mine, requires you to use an SLR, I highly recommend the Canon EOS-3. It's metering is the best I have ever come across. --------------------------------- ----------------------------------------------------------------------

-- Dayton P. Strickland (daytonst@bellsouth.net), February 09, 2002.

Re Andy's point, I'm not sure if number of elements is the whole story, although zooms are definitely prone to more flare. Old pre-WWII Leitz lenses used to have far more elements and glass/air interfaces than Zeiss. Leitz lenses had better resolution, Zeiss had better contrast. Today's Leica lenses are more contrasty through use of multi-coating, but still have six or seven elements. Another very simple but highly praised lens today is the Zeiss Tessar found on the tiny Yashica T5, which (I think!) has just four elements. It's praised for being sharp and contrasty. I think there are heap of highly complex factors which need to be taken into account. Lens expert Erwin Putts at www.imx.nl is the guy to check out.

-- David Killick (dalex@inet.net.nz), February 09, 2002.

Andy raises a good point concerning primes vs. zooms: years ago I purchased an old 135mm f2.8 lens which had, I believe, six elements. To test it out, I mounted a camera to a tripod, and used both the 135mm and a 70-210 zoom set at 135mm to shoot some test slides. To make a long story short, the comparison showed that the zoom's true f-stop (I think they call it a "T-Stop" in motion picture camera lenses) at a given setting was considerably smaller -- about 1/2 stop -- than the indicated setting. At 135mm, the zoom's setting indicated f4 as max aperture, but it was effectively about f4.8, or a half stop slower, a fact I only discovered by comparing the readings to those derived using the prime lens. I surmised the difference to be accounted for by the zoom's larger # of elements (about 11, I think) diminishing the light as it traveled down the lens. Even well-coated lenses will lose some light to flare.

In practice, it means that good prime lenses may be even faster, in comparison to zooms, then indicated by their published maximum apertures.

-- Douglas Kinnear (douglas.kinnear@colostate.edu), February 10, 2002.

Someone showed me a picture of a cat's face in 1966, with each whisker in the Black and White print sharply defined. It convinced him to give up his well-known SLR. When it comes to Leitz...or now, Leica, you can use all kinds of lens studies to prove a point, but it's really magic. Don't question it, just use it, just like photographers have been doing since 1925, with the same fabulous results. I use a Leitz V15 enlarger to cast an even sharper spell. Zap....magic, plain and simple.

-- Maurice J. Tepper (judiknit@earthlink.net), February 13, 2002.