Pentax (lens)

Pentax smc FA 31mm F1.8 Limited

Pentax lenses were first badged as Takumar. The Takumar branded lenses were well respected for their line of Super Takumar, which designated the high performance coating applied to the lens as well as the optical formulas used to make them. The majority of the industry at the time was still satisfied with the variations of the "plumb" coating process and later some of the two and three layer processes as well. Asahi Pentax soon introduced the Takumar Super-Multi-Coated line of lenses which was a 7 layer process as the industry had just caught up with similar forms of 5 layer multi-coated optics. Eventually Asahi Optical and Pentax slowly shifted much of their lens production under the Pentax name and transitioned some of the successful designs that were first introduced under the Takumar name to use Asahi/Pentax badging as well as beginning to use the "smc" abbreviation. Eventually the Asahi partnership disappeared and the Pentax name became solely used. Pentax lenses saw many feature changes to answer the market, such as: incorporating "Auto-Aperture" with the M42, the light weight and compactness with the 'M' series, Aperture Priority overrides with the 'A' series, and Auto-Focus with the FA series. Modern Pentax lenses have seen the elimination of the aperture ring completely as found on Pentax DA and DA* lenses Pentax digital SLR cameras. They use the Pentax KAF(And its variants, KAF2 and KAF3) Mount. All of these lenses have an autofocus feature, either operated from the camera body or from an internal SDM motor. Pentax compatible lenses are also made by third-party companies.

History

Takumar brand lenses were primarily supplied with Pentax cameras through the 1950s and 1960s using the M42 (Pentax) Screwmount. Asahi Optical soon began supplying lenses under the Pentax name in the early 1970s, and introducing the bayonet (K) mount at the same time. The semi-official 'K' family lenses are mostly of the original Takumar Super-Multi-Coated production or in other words the 7-layer process multi-coated versions that have been adapted from the M42 mount to the K-mount. The change to the bayonet also had an impact in the industry as many other brands utilized the M42 mount and enjoyed the compatibility. Similarly, the introduction of the 7-layer coating first used with the Takumar name and later as Pentax raised controversy. It had doubters to its durability as well as its claims of flare control. Pentax's had confidence in the technology and demonstrated this by keeping a lock on the patent for quite a while. Asahi Optical and Pentax did not keep a strictly closed door on R&D as they had active partnerships with Zeiss and Tokina as well as others. Thanks to the special research and attention, the appearance of the special STAR series lenses made their debut. Pentax has always been active as most in special run lenses such as for example the Infrared quartz element lens. In addition to the 35mm line, Pentax added professional medium format 645 and 67 cameras lenses to its lineup. With such a formidable list of lenses, it is no wonder that Pentax's digital interchangeable-lens camera bodies maintain compatibility with any Pentax K mount and even the M42 screwmount (with a Pentax adapter) ever made, thus providing countless lens possibilities. 35mm and 645 lenses optimized for digital cameras are currently in production.

Controls, features and changes

S-M-C & smc

Auto-Aperture and Bayonet

Next improvement appeared in the addition of the 'A' button. Star lens

Rubber-sealing on the back of the DA 50-200mm 1-4-5.6 ED WR (red, right) compared to the non-WR version of the lens (left). There are further seals on the inside of the lens that are not externally visible.[1]

Unlike many manufacturers, Pentax provides "shake reduction" (SR) functionality within the camera, instead of inside each lens to be purchased. This is advantageous as any lens can be used with full SR functionality, and the lenses are more economical to manufacture as they do not require any shake reduction equipment inside.

Limited

Another feature which sets Pentax lenses apart from other manufacturers is that many of their lenses, like their medium- to high-end camera bodies, are weather-sealed, allowing for their continued use in poor weather and wet locations.

Lenses marked as WR bear a “simplified weather-resistant construction […] which makes it difficult for water to enter the lens” compared to the DA* and AW lenses, which are “dust-proof and water-resistant”.[2] Pentax currently provides weather-sealed premium lenses up 560 mm. The largest lens produced by Pentax was the Reflex 2000mm, with non-mirrored lenses available up to the A* 1200mm. As with most manufacturers, telephotos of this range are no longer in production. Pentax provided premium focal lengths well beyond 1200mm, such as their 3800mm through the Pentax telescope division.

Latest coatings

Mounts

Main article: Pentax K mount

Lens designations

Pentax smc M 50mm f2

Below is a list of K-Mount Lens Lines produced by Pentax.[3]

K lenses

The first generation of Pentax K-mount lenses. Officially not referred to a K series lenses, they usually are given this designation to distinguish them from later K-mount lenses (such as the M, A, F, FA and DA series). These were exclusively manual focus lenses with no electronic features. The name of each lens started with "smc", for example smc Pentax 28mm F3.5, where smc stands for Super-Multi-Coated, the lens coating introduced in the early 1970s at the end of the M42-mount era.

M lenses

The M series of lenses followed on from the earlier K series lenses. As with the earlier lenses, these were manual K-mount lenses without any electronic features. They behave just like the K series but are generally smaller in size, to match the more compact bodies of the same era, e.g. the Pentax MX and the Pentax ME Super.

A lenses

Another K-mount lens, the A series of lenses saw the introduction of "automatic" aperture settings. The lenses had an aperture ring (unlike the later DA series), and thus the aperture could be set manually, but they also had an "A" mode, which allowed the camera to control the aperture automatically.

F lenses

The F series were the first autofocus lenses (excluding the rare smc Pentax-AF 35-70mm F2.8, made only for the ME-F camera). The autofocus is of screw-drive type, still supported by all Pentax DSLRs. They featured an aperture ring, which allowed the aperture to be controlled manually. Thus F lenses are able to be used on older cameras which do not support automatic setting of the aperture, such as the Pentax K1000.

FA lenses

Pentax smc FA 35mm f2

These lenses are designed with use for full-frame film SLR cameras. As with the F series, they feature an aperture ring providing compatibility with older camera bodies. Autofocus is like the F series of screw-drive type. The FA* lenses are professional grade lenses and the FA Limited lenses are all metal high quality primes. The FA series has been superseded by the DA and D FA series optimized for digital cameras, but as of March 2015 the three FA limited as well as the FA 35 mm f2 and 50 mm f1.4 are still in production.[4]

FA-J lenses

The FA-J series consisted of three lower-priced zoom lenses, that were largely identical to the FA series of lenses, but like later DA series lenses lacked the aperture ring. As a result, they are not fully compatible with some older manual film cameras, as there was no method of setting the aperture other than through the camera body.

D FA lenses

smc Pentax-D FA 100mm F2.8 Macro WR

These lenses are coated with glazes that make the lenses more suitable for digital cameras. However, they also support older 35mm camera formats, as they provide full frame coverage. The series originally consisted only of two macro lenses – a 50mm and a 100mm – which both featured an aperture ring. In 2009 the 100mm was replaced by a weather resistant (WR) version without an aperture ring,[5] that was co-developed with Tokina.[6] The series was revived in February 2015 when the D FA* 70-200mm f2.8 and D FA 150-450mm f4.5-5.6 telephoto zoom lenses were announced[7] along with first pictures of a (then unnamed) K-1 mock-up.[8]

DA lenses

The WR version of the 18-55mm kit lens

The DA lenses were designed specifically for the Pentax digital cameras incorporating an APS-C digital sensor. As the APS-C sensor has a smaller surface area than 35mm film, these lenses are not generally considered to be compatible with older cameras. They also lack an aperture ring, limiting their use on cameras that do not support automatic aperture settings. Most of the DA zoom lenses are available in weather resistant (WR) versions to match the weather sealed capabilities of the medium to upper level Pentax DSLR camera bodies. While older models still have the in-body screw drive autofocus system, newer designs marked "DC" or "SDM" feature silent, in-lens autofocus motors.

Some lenses of this product line were co-developed with Tokina. Examples include the DA 12-24 and the DA 10-17 Fisheye.[6]

DA-L lenses

These are lighter and cheaper versions of DA series zoom lenses. They have a plastic (as opposed to steel) mount and lack the quick-shift focusing system of their heavier siblings. They are only sold in kits with entry-level bodies.

DA* lenses

Pentax DA* 16-50mm f2.8 alongside the smaller Pentax DA 18-55mm f3.5-5.6 lens

The DA* lenses are designed for use with Pentax digital SLR cameras. DA* lenses have higher quality optics and feature a higher level of weather sealing (AW) than most DA lenses (WR). The DA* lenses are more expensive and generally feature improved light transmission and larger aperture openings for better low light performance. Some DA* lenses also feature both body driven screw drive focusing and the Pentax SDM (Supersonic Drive Motor) lens based focus mechanism.

Some lenses of this product line were co-developed with Tokina. Examples include the DA* 16-50 and DA* 50-135.

DA Limited lenses

These are high quality (mostly prime) lenses with the lens housing made of metal. They usually have a wider maximum aperture compared to zooms but narrower as compared to other prime lenses. This is a compromise as DA Limited lenses are usually made to be much more compact than other primes lenses. In August 2013 the DA Limited lenses were upgraded with Pentax new HD coating, replacing the previous smc coating.[9] The new HD lenses are also available in both silver and black, as opposed to only black.

The DA 35/2.8 Macro was co-developed with Tokina.[6] As of February 2015, the DA 20-40mm F2.8-4 Limited DC WR announced in November 2013[10] stands out for being both the only zoom as well as the only weather resistant lens of the series.

Lens variations

Series Prime Lenses Zoom Lenses
K series 34 7
M series 22 8
A series 28 11
F series 8 9
F* series 1 2
FA series 12 19
FA* series 3 8
FA J series - 3
D FA series 3 5
D FA* series 0 1
DA series 17 20
DA* series 3 3
DA XS series 1 -
DA L series - 5

Supersonic Drive Motor (SDM)

The Pentax-developed SDM autofocus systems, with SDM standing for "Supersonic Drive Motor", departs from the previous Pentax system which utilizes a screw-drive autofocus motor inside the camera body. Instead, SDM lenses incorporate an autofocus micro-motor as part of the lens itself. All current production Pentax Digital SLR bodies are compatible with SDM lenses. However the DA* 55mm, DA 17-70mm and DA 18-135mm lenses are not compabile with some older Pentax digital SLR's such as the K110D, first version K100D and earlier models (The K100D Super is compatible, provided it has up to date firmware).[11]

The SDM mechanism is claimed to provide smoother and quieter focusing.[12] The first Pentax cameras to support SDM lens were the K10D (firmware 1.30 or later) and K100D Super. These and subsequent Pentax DSLR bodies support both SDM and in-camera screw-driven AF.

Camera compatibility

Pentax claims that all their auto-focus cameras are backward compatible with K-mount lenses dating back as far as 1975 without need for an adapter. However, the camera cannot read the set f-stop of K and M series lenses and must stop-down momentarily to meter (Due to their digital cameras having a "Crippled K-Mount"). All Pentax and Samsung D-Xenogon lenses are interchangeable since Samsung adopted K-mount on their GX camera bodies.[13] The Samsung GX-10 and GX-20 are the only two models compatible with SDM lenses. Pentax KAF3 Lenses do not have screw driven autofocus, and are also not fully compatible with some early production digital SLRs.

List of lenses in production

Below is a list of lenses in production as of February 2015.[4][14]

List of some out of production later generation Pentax lenses

Lens Aperture Type
16-45mm F4.0 DA
18-55mm f/3.5-5.6 DA
18-55mm II f/3.5-5.6 DA
18-250mm f/3.5-6.3 DA
20-35mm f/4 FA
28-80mm f/3.5-5.6 FA J
28-105mm f/3.2-4.5 FA
50-200mm f/4-5.6 DA
75-300mm f/4.5-5.8 FA J
100mm Macro f/2.8 D FA
600mm f/4 FA*

References

External links

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