Leica 21-24-28 Viewfinder
A Limited View
In early 2001 Leica made available a new multi-focal length wide-angle viewfinder for its M series cameras. The viewfinder has three settings; for 21mm, 24mm and 28mm lenses. Such viewfinders are needed because the built-in viewfinder / rangefinder of a Leica M6 can only display focal lengths as wide as 28mm, and that only with decent eye relief on the latest .58 magnification viewfinder model.
Leica currently makes 4 lenses in this range (21mm, 24mm, and two 28mm) and which few would argue are among the finest ever made. These are the 21mm f/2.8 Elmarit-M ASPH, the 24mm f/2.8 Elmarit ASPH, the 28mm f/2.8 Elmarit-M and the new 28mm f/2.0 Summicron.
There are separate viewfinders for each of these focal lengths, available at around $250 each. The new multi-focal length viewfinder costs about $275. If you own or eventually plan on owning more than one of these focal lengths the economic motivation for this viewfinder is obvious.
As I removed it from its case for the first time the thing that struck me was that though it says Leica Camera Germany on top, on the base of the shoe mount is written, Made in Japan. Presumably this viewfinder is OEM'd from a Japanese contract manufacturer. This may be of concern to some Leicaphiles but doesn't detract one bit from the fact that this is a precision manufactured optic. Whether it's worth $275 is of course up to the individual purchaser. Some complete cameras and lots of lenses cost less than this.
Features and Flaws
The viewfinder is made of anodized aluminum and it has a locking shoe mount. It is available in either a chrome or black finish and is of five-lens construction. The eyepiece end has a rubber cap so that eyeglasses won't be scratched, and the first glass surface is recessed enough so that oil from eyelashes are unlikely to be an issue. The front element of the viewfinder is exposed, and quickly becomes the repository of countless fingerprints.
The three-position knurled setting ring for selecting focal length has positive click stops, but I have found that it can be knocked slightly off position with only moderate handling.
As can be seen in the photograph below the viewfinder is canted slightly to the left of the hotshoe position so that it sits squarely over the lens, eliminating one aspect of possible parallax error.
Though Leica claims that the viewfinder is suitable for wearers of eyeglass I find this to be marginal at best. Curiously though, I find that with this viewfinder I don't need to wear my glasses at all. Since my prescription is +1.5 this means that the viewfinder must have approximately this diopter setting so as to be able to give me a clear unaided view. I guess Leica assumes that all its customers are middle aged and nearsighted.
The view through the device is very crisp and bright. There is some barrel distortion, but not enough to be of concern, and certainly less than that of a number of WA accessory viewfinders I've seen.
One gripe is that there are no frame lines. The image frame selected fills the viewfinder. This means that one isn't able to see outside the delimited field of view, something that I appreciate in rangefinder cameras and viewfinders that do feature bright frame-lines.
My other minor concern is that the shoe mount extends beyond the rear edge of the mounting shoe. This is necessitated by the large size of the knurled wheel used to secure the viewfinder to the shoe. The downside of this is that the camera's wind lever can not be opened with the edge of ones thumb, but instead must be "released" to the open position by nudging it free from the top. A potential slower-downer in a rapid shooting situation if the wind lever starts in the closed position. Incidentally, this problem also exists when the SF20 flash unit is attached. In both instances the use of the M Motor alleviates the problem.
Overall, and notwithstanding the high price, if one has more than a single lens in the focal range covered the new Leica 21-24-28 viewfinder does an admirable job.