The 28 Summaron
In ‘Viewfinder’ 2/16, in my article “Not a Collector”, I told of the consequences of my acquisition, many years ago, of a 28mm Summaron for a Leica IIF that I owned. Imagine my surprise when only a few months after the article was published Leica announced that they were producing a new series of these lenses in the M mount in order to exploit the much loved characteristics of a typical lens from the fifties era!
Although it was introduced very shortly after the iconic M3 became available in 1954, the original 28mm Summaron was only ever produced in screw thread mount. As it was the only 28mm available at that time it was also offered for M cameras with an appropriate screw to bayonet adapter. The lens was then discontinued in 1963 just before the first 28mm f/2.8 Elmarit became available for the M cameras. Total number produced has been quoted as just over 6000 so that the lens is relatively rare and has appealed mainly to collectors. A pity because it is a very good lens and with the ISO speeds available with today’s digital cameras the f/5.6 maximum aperture is no problem for most photographic needs.
The original (on the right) and the new 28mm Summaron (on the left) each with their lens hood.
With the new Summaron-M, however, we have an unusual opportunity to enjoy one of those earlier Leica lenses and to appreciate not only the characteristic optical style but also the compactness and elegance typical of the period.
MOUNT DESIGN & HANDLING
Courtesy Leica, I was recently fortunate to be able to try one of the new Summaron-M lenses and to compare it directly with my 1956 series lens. There are some minor differences in the construction of the two lens mounts. None of these are of any significance. The only one of any practical relevance is for anyone wishing to use the old A36 size filters on the new lens. The front of the new mount is almost 2mm greater diameter than the old. Not much, but it prevents the old A36 filters from fitting over it. Conversely the lens-hood for the new lens will not fit the old lens. As the old lens-hoods in mint condition are rare and can only be bought for astronomical prices this could be a disappointment for those owners of the older lens who might have hoped to have a source for a replacement. In any case the new hood has a smooth finish rather than the crackle of the original. The new lens has a 34mm screw-in filter size. These may be a little difficult to find but Heliopan make them and a number of dealers will supply them to special order.
The front element of the Summaron is well recessed in the mount and the hood is hardly necessary unless you are using a filter. It is effective but detracts significantly from the exceptional compactness of the lens. It also intrudes slightly into the bottom right hand corner of the viewfinder frame and I found that operating the aperture ring could sometimes be a bit fiddly with the hood in place. Generally speaking I tended not to bother with the hood! The click stops (these are only at full aperture settings) are positive. Focusing is smooth but as was normal for the period the closest focus of one metre needs almost a full 180-degree rotatation from infinity. You also have to remember to depress the infinity catch when moving off this setting! The illustrations of the IIf and the MP each with their contemporary lenses show how in the new iteration of the 28mm Summaron the knurling and lettering style have been very subtly adjusted to match current norms.
Hello, World!
A Leica MP with the Summaron-M 28mm, a chrome Summicron 35mmf2 and a chrome Summicron 50mm f2.
A Leica IIf with its contemporary 28 and 35 Summarons and a 50mm red scale F3.5 Elmar. Note the then current styling.
OPTICALLY
The optical construction of the new lens is nominally identical to the earlier version. However, Leica have said that changes in the availability of types of glass over the sixty years between the lenses has necessitated some very minor adjustment to accommodate these. Nevertheless, the lens’ cross-section and MTF curves that have been published for the two lenses appear to be identical. More obviously there are differences in the colour of the coatings. This is not surprising, coating technology has advanced enormously since the fifties and the new version of the lens has benefited. As with the original lens, click stops are only in full aperture steps and the closest focus remains at 1 metre. The lens is 6-bit coded and the information is recognised in the exif data.
PERFORMANCE
At f/5.6 the 28mm Summaron is an excellent performer with outstanding detail over all but the edges of the frame. Stopping down to f8, which is probably the optimum aperture, brings in first class detail in all but the extreme edges and corners of the frame. Leica themselves point out that from this point onwards further stopping down improves the edges but there is a slight reduction of central performance due to increasing diffraction. This is apparent from the published MTF curves. The lens only focuses as close as 1metre but the performance is still very good at this distance. Performance against the light is excellent with good freedom from flare and reflections.
Distortion is practically zero but vignetting is another matter. At full aperture this is 2.5 stops and at f8 it is still 1.8 stops. The lens is 6-bit coded so that the firmware on the M digital cameras does of course reduce these figures.
When I ran some comparisons with my 60-year-old original there is greater overall clarity and overall higher contrast throughout the image area. To my eyes the necessary optical changes and the newer coatings have had a useful effect without affecting the classic rendition.
GENERAL
This is a lovely little lens. Its compactness and traditional aesthetics are very appealing. It is also light and small enough to easily find a convenient corner in the gadget bag yet it is still capable of excellent performance even by today’s standards. Travelling light this lens together with a 90mm Macro-Elmar- M makes an especially versatile and pocketable combination capable of really excellent results.
