OK, after going through parts one and two of this series, you are uber-excited with adapting lenses in your mirrorless camera, have weighted the pros and cons of the operation and now need to find out more about what choices there are out there.
Here is a shopping list of sorts then, which I have no illusion of it being a full dissertation on this complex matter. I just hope it shows a general direction for anyone interested, complete with some noteworthy examples.
First off, let's make a distinction between "I happen to have it" vs "I'm looking for it". The first category is virtually self-explanatory. The second begs the question: looking for what and, especially, what purposes.
If the goal is to have just another creative flavor, then, be my guest, adapt whatever tickles your fancy. In this regard, even CCTV lenses have been adapted for use with micro four thirds cameras, native mounts and all.
If, however one searches for serious alternatives, in rendering character, but also perhaps sharpness, contrast and color comparable or superior to native lenses, then this becomes a different story. I will try to approach the matter from this angle, offering my opinions by type of lens, according to focal length.
In order to keep things simple, as well as practical, as possible... let's quickly forget about film-era manual zoom lenses. Truth be told, they were not very good, in my opinion, inferior to even consumer grade zooms of today. Apart from that, working with a manual focusing zoom is rather masochistic in my humble opinion. That said there are a couple of very high caliber zooms from that era; e.g. the Olympus OM 35-70 f/3.6 or the Contax/Yashica 28-50 f/3.5, but these are far and between. Not mentioning they are very heavy too...
Let's also quickly address the 35mm digital or "full frame" dilemma: Sony FE only has about 7 available native lenses at the time of this writing. As a result, any adapted lens can potentially offer an advantage in overall system maturity. An added bonus for this system is that lenses work at the focal length they were "supposed to", but this is also a handicap. Here the whole image circle is used, which means that softness in the corners and/or vigneting is a real possibility. Additionally, having sensors with high pixel count, further adds to the burden on lens performance. A case by case evaluation is preferable.
For the smaller mirrorless systems, namely m43 and APS-C, things are somewhat more complicated.
Starting with UItra- and wide angle: This is a mixed bag; there are certainly some great lenses here but keep in mind the distortion factor and no auto-corrections (see part 2)
For m43 there is almost no point preferring 135-format wide-angles above 18mm, since they become "standard" equivalent lenses. Nowadays there are excellent choices at 15-20mm (Olympus, Panasonic, even Sigma), 25mm (Panasonic, Olympus, Voigtlander). Even at the ultra-wide end, there are several high-end native choices. What may be interesting is adapting 35mm focal length lenses, which are abundant and some of them very good optically and quite small, while there are some fast ones (e.g. f/2) which will make a good short-portrait 70mm equivalent lens for the system.
For APS-C, about the same as with m43 is true, only that the low limit may now include some 24 and 28mm glass. That said, f/2 or f/2.8 lenses on these focal lengths were always expensive, due to high demands on the optical design. 35mm is also not that hot a proposition, except for some very desirable (and costly) options, because there are now very competent native AF lenses for every APS-C mirrorless system.
Going to 45-60mm focal length (also called a "standard" lens in 135-format parlance) this is considered a normal portrait-short telephoto lens in the m43 ecosystem. There are some incredible native choices already, either in performance and/or in the value for money department. That said, a number of fast (at least f/1.8, preferably f/1.4 or faster) legacy lenses have proven to work very well. This is the category with the most options and, indeed, the best overall value for money. With an APS-C sensor these lenses are considered short/normal portrait, and, again, many interesting options exist.
Anything longer than ~60mm becomes shorter or longer telephoto for both systems. There are several "traditional" focal lengths from the film days; namely: 85mm, 100mm, 105mm, 135mm, 180mm etc. APS-C and, especially, m43, virtually gain "free telephoto reach"; just imagine shooting a 300mm f/5 lens with m43, it has the same FoV as a 600mm in 135-format terms and, currently, there is no native lens at this aperture speed. It's no wonder then that many people shooting nature are adapting such lenses. Again, caution should be exercised apropos to weight (remember... metal and glass...) and also, let it be noted that old telephotos weren't particularly sharp wide open. The problem is that, modern crop cameras start to show diffraction starting from f/8- f/11 which practically limits the available apertures for these lenses in a very tight range. Handholding such a lens, becomes cumbersome as well as prone to shake blur; that can be defeated by higher ISO and/or in-camera stabilization systems (Olympus/Panasonic).
Any macro will work great with m43, given the advantages in this department offered by the system's sensor size and the same is proportionally true with APS-C. All systems now have very nice native macros; the problem for some people is that they are, more often than not, quite expensive. If the needs for a macro lens are sporadic, an adapted one is a great option. Let's remember that, manual focus is the norm for macro work anyway.
I would say any special purpose lens, incl. fisheye, tilt-shift, etc, are not interesting. There are tilt-shift adapters, where you can mount any lens and a 12mm or longer fisheye is not particularly interesting on a crop body; better prefer a native lens.
Now let's examine some of the favorite legacy systems, with examples on specific lenses:
Leica rangefinder lenses, which come in screw or bayonet type, speaking either of the genuine item or third party, from Zeiss, Voigtlander and others, were always the darlings of the adapting crowd. Without doubt, mechanical and optics quality is high with these lenses, as are, let's admit it, bragging rights! Leica M lenses may be viewed as an investment, since they retain their high asking price easily. There is also one more advantage to adapting: since the flange distance was already very short in the original, this means the adapters to mirrorless are also very thin, and the overall size diminishes.
If one wants to invest in such lenses, there are some more economical propositions from Zeiss and notably Voigtlander, which are not far in terms of quality and performance. The interesting part is that most of the lenses in this category can be bought brand new, since Leicas and copies never stopped being produced. Another interesting point is that there are also a few East European copies for the Leica-M mount, which can be bought for pocket money, and allow for experimentation. Among them, some are actually good optically also; e.g. the Jupiter-9 for screw mount M39.
Although still quite expensive, Leica SLR lenses are certainly more affortable than Leica-M; at about the same level as Zeiss-Contax lenses. They are larger too, which reduces their desirability for smaller cameras. Still several versions in 35mm, 50mm and 90mm focal lengths are good options, especially for full-frame mirrorless.
Nikon is almost unique in this crowd (apart from Leica, of course) in that, any SLR lens made in its history, can be used, one way or another, with virtually any SLR camera they've made, analog or digital. The mount has remained unchanged and the only things missing may be autofocus, aperture coupling for stop-down and metering, etc. Working in a completely manual fashion is almost universal in compatibility.
For adaptation to mirrorless, either older F lenses (either Ai or pre-Ai) and newer D-type ones are equally valid, since they all have aperture rings. The selection is so large that would need several articles, so I'll just reference some notable choices; from the somewhat extreme like the 50mm and 58mm f/1.2 to some brilliant underdogs, such as the 100mm f/2.5
Pentax M42 screw mount is perhaps the most popular choice for adaptation, since there are so many options to choose from . This is mainly because this mount was used in several cameras made in the former Eastern-Block. Soviet Union and other Eastern Europe countries made hundreds of thousands of lenses for this mount, most, if not all of them, being copies of great Western designs (e.g. Zeiss). One can imagine that general build quality as well as optics vary wildly. But in reality, most "communist" M42 lenses are at least decent and in many cases very good; also always built like the proverbial tank. Of course, M42 mount lenses were also made in West Europe and Japan, some of them of exemplary overall value.
M42 variety is bewildering, so I'll only mention a few: there are dozens of 50/55/58mm options that can be had for as low as 20€ in good condition, a couple of legendary 85mm (Pentax and Jupiter) and a whole bunch of 135mm lenses in f/2.8 and f/3.5 apertures, which are very interesting especially for full frame shooters, due to their good sharpness and bokeh characteristics.
The original Olympus Pen was the brainchild of famous Olympus designer Yoshihisa Maitani. It's hard to tell from looking at it, but it was a genuine SLR camera, it just shot half frame instead of the full 36x24mm. As a result of this remarkable feat in engineering, size was held at a minimum and that is true of lenses also.
Old Pen system lenses are a great option for smaller m43 cameras in particular. They are adequate to cover the APS-C size sensor (half frame is a bit larger than APS-C) so they might work well with APS-C mirrorless also. Their focal lengths are interesting in that they equate with "standard 135 format" on a 1.5x crop. Some of them are quite bright and sharp; worthy of mention are the 40mm f/1.4 and f/1.2, the 38mm f/1.8, the 60mm f/2 and the very small 38mm f/2.8 pancake.
Minolta, long before Sony bought the rights to their name and patents and even before their more modern, film era AF lenses, were making the Rokkor MC/MD line of manual lenses. Typical of the era they are quite small, all metal and very dependable mechanically. Among them there are some highly desirable ones, such as the 135mm f/2, the 50mm and 58mm f/1.2 and the 85mm f/2 and f/2.8 Varisoft. They are fairly well priced, and others such as the various 50mm f/1.4 are even more affordable (and quite good too). Minoltas, like most lenses of that age, have their own distinctive rendering signature, which is why a lot of people adapt them for modern cameras.
The Olympus OM mount was developed for the OM line of film cameras, and went away when Olympus failed to convincingly enter the AF era. These are beautiful small-size lenses, with great optics and very good build quality, making them a great choice for mirrorless users. There are some extreme designs, demanding high prices, such as the 50mm f/1.2 and several f/2 versions of wide-angles. There are also several more economical but quite beautiful examples, such as the 35mm f/2, 24mm f/2.8, 85mm f/2, 50mm f/3.5 macro and 100mm f/2.8.
Contax/Yashica SLRs were notable for some very adventurous technical innovations (e.g. moving "auto-focusing" film plane) and also great attention to detail and mechanical excellence. But perhaps the most exciting part was always the Zeiss lenses they came with. Zeiss made lenses for several other mounts (virtually the same optics and construction) but here we have a complete line-up. Lenses such as the 85mm f/1.4, 135mm f/2.8, 50mm f/1.4 and less glamorous ones, like the 85mm f/2.8, 28mm f/2.8 etc, are very much sought after for adapting in a variety of cameras. Prices are average to high, depending on lens and condition, and the German-made ones fetch the highest prices (although I believe Japanese models to be as well made). Aside from objective qualities, Zeiss also have their own "signature" image rendition, which is what attracts most people anyway.
FD is the older, manual lens mount for Canon cameras, before the introduction of the EOS system. Canon used to make them for quite some time, which means there is a vast selection of them in any focal length. While they were never considered equal to comparable SLR lenses from Nikon or Zeiss in their day, there are some extraordinary examples among them, such as the 85mm f/1.2L, 50mm f/1.2L, 135mm f/2 and 24mm f/1.4L. These usually fetch a hefty price on ebay and other online outlets, while there are less spectacular, slower versions, of these FD lenses which are much more affortable and quite effective. On the other hand, nothing can beat a f/1.2 lens wide open especially for videographers and creative photographers not that much concerned with extreme sharpness wide-open. Be advised that, the fastest lenses are also quite hefty and probably not the best choice for smaller mirrorless bodies.
Contax G1/G2 were rangefinder-like, electronics-driven, modern AF film cameras. The main interest with the lenses here is their size; they are the same size or smaller than many modern mirrorless system lenses of the same focal length, and still covering the full 36x24mm sensor. They are therefore a very good option if the specific system doesn't have an equivalent lens of equal optical quality. Speaking of optics, the lenses were made by Zeiss and are considered excellent. Finally, there is at least one adapter that allows (slowish) autofocus with the Sony E and FE mount cameras. Prices are rather rational; although they have also risen during the last years. Notable lenses: 28mm f/2.8, 45mm f/2, 90mm f/2.8
This concludes this small series on adapted lenses, but it's not the final word on the subject; rather an introduction of a kind. There will be more in this blog, with specific examples of adapted lenses, so please stay connected!