• The second generation of autofocus lenses
• Automatic aperture setting is available*
• Full-frame lenses
• Certain zoom lenses feature the power zoom function**

Remarks: Lenses in this series are autofocus and allow for certain modern cameras (film and digital) to automatically set aperture (Tv mode), shutter speed (Av mode), or both (Program mode). You can also set exposure manually if the camera body allows for this. On recent camera bodies (e.g. *ist, *ist D, DS, DS2, DL, DL2, K10D, K100D and K110D) you use dials on the camera body to set aperture as well as shutter speed (the aperture ring on the lens must be in the "A" position at all times). On older models (such as ZX-5N, MZ-5N, LX, ME, MX, K1000) the aperture is set with the aperture ring on the lens and the shutter speed is set with a knob on the camera.

Three FA "Limited" lenses were made available in 2001. The FA series, which consisted of 42 lenses total, has been discontinued except for these lenses.

The FA series also includes 11 "star" lenses (FA*) that employ the finest of Pentax optical and mechanical engineering.

*Exceptions: The SMC Pentax-FA Soft 85mm F2.8 and SMC Pentax-FA Soft 28mm F2.8 lenses have no "A" setting on the aperture ring. Hence they work like M lenses with respect to exposure; they are still autofocus. The "A" setting has been removed because the degree of image softness is controlled by the aperture ring alone.

**Power zoom is only supported by certain camera bodies. The following lenses feature power zoom:

-SMC Pentax-FA 28-80mm F3.5-4.7
-SMC Pentax-FA 28-105mm F4-5.6
-SMC Pentax-FA 70-200mm F4-5.6
-SMC Pentax-FA 100-300mm F4.5-5.6
-SMC Pentax-FA* 28-70mm F2.8 AL
-SMC Pentax-FA* 80-200mm F2.8 ED [IF]
-SMC Pentax-FA* 250-600mm F5.6 ED [IF]

• First generation autofocus lenses
• Full-frame lenses
• Automatic aperture setting is available

Remarks: Lenses in this series work just like FA lenses; see above for features and limitations.

The F series consisted of 20 lenses is now fully discontinued.

The F series also includes 3 "star" lenses (F*) that employ the finest of Pentax optical and mechanical engineering. 

• A small series of 3 autofocus zooom lenses
• Full-frame lenses
• Automatic aperture setting is available, but there is no aperture ring

Remarks: SMC Pentax-FA J lenses lack the aperture ring but otherwise work like an FA lens set permanently to the “A” position. Due to the lack of an aperture ring these lenses cannot be used on camera bodies where use of an aperture ring is mandatory (such as LX, ME, MX, K1000), but can be used on e.g. the ZX-5N in Program and Tv mode. These lenses provide full functionality on all recent bodies like the *ist, *ist D series and K (digital) series

• The current generation of autofocus lenses
• Only usable with APS-C Digital SLRs
• Automatic aperture setting is available, but there is no aperture ring

Remarks: smc PENTAX-DA and smc PENTAX-DA L lenses work like FA J lenses. They have a smaller image circle and are designed to be used exclusively on digital cameras with an APS C sized sensor (the K and *ist D digital camera series).

DA lenses (except for the 18-250 mm zoom) feature a "quick shift" focusing system that allows the focus to be fine tuned on the lens without setting the camera focus selector to "MF".

The DA L lenses are a light weight edition of their DA counterparts. They have a bayonet mount made of plastic rather than stainless steel and they do not have the quick shift focusing capability.

The DA series includes a number of "star" lenses (DA*) with top notch optical and mechanical engineering.

Currently (September 2009) the DA lens line-up includes two lenses (DA* 55 mm and DA 17-70 mm zoom) which will only autofocus on the K10D, K100D Super, and newer Pentax cameras. These two lenses lack the traditional screw drive autofcus coupler.

Many users report that the smc PENTAX-DA 40mm F2.8 Limited, also known as "the pancake," covers the full 24 x 36mm frame and thus is compatible with film bodies. Optically it is based on an earlier lens in the M series.

• Current generation of autofocus lenses for Film as well as Digital SLRs
• Full-frame lenses
• Automatic aperture setting is available, and there is an aperture ring

Remarks: smc PENTAX-D FA lenses work like FA lenses. They have been optimized optically for digital sensors but work equally well on a 35 mm film camera. Their image circle covers the full 24 by 36mm negative format. These lenses provide an easy way to manually fine tune the subject distance set by the autofocus system ("quick shift" focusing system).

• The third generation of manual focus lenses
• Full-frame lenses
• Automatic aperture setting is available

Remarks: smc PENTAX-A lenses are manual focus. Regarding exposure control they work like FA lenses.

The A series also includes 9 "star" lenses (A*) that exemplify the finest in Pentax optical and engineering.

• The second generation of manual focus lenses (generally smaller than K lenses)
• Full-frame lenses
• Manual aperture

Remarks: smc PENTAX-M and smc PENTAX (commonly know as "K") lenses are manual focus and have no "A" setting on the aperture ring. These lenses allow for the camera to automatically set shutter speed (if it has the Av auto-exposure mode). You can also set exposure manually if the camera body allows for this. The ZX-5N is an example of a body which provides Av mode as well as manual exposure mode with M and K lenses. Almost all K and M lenses have an automatic diaphragm.

Some recent bodies cannot use M and K lenses or only with some limitations. An example are the *ist D and K (digital) series. In M mode you set the aperture using the aperture ring on the lens; the camera will set the shutter speed when you press the green button (or AE-L button if the camera has no green button). Or you can set the shutter speed manually (there is no exposure read out in the finder to assist you).

The M series includes a single "star" lens (M*) that exemplies the finest in Pentax optical engineering. That is the smc PENTAX-M* 300mm F4.

• The first generation of manual focus lenses
• Full-frame lenses
• Manual aperture

The following abbreviations are used in lens names:

SMC: Super Multi Coating, Pentax's multi-layer lens coating applied to almost all its lenses which greatly reduces flare.  DA, D FA, and some FA lenses feature "ghostless coating" that does an even better job.
WR: Weather Resistant. The lens is sealed against dust and light rain.
SDM: The lens has a built-in super-sonic motor for autofocus (K10D, K100D and newer cameras can take advantage of this).
IF: Internal focusing. Focusing is achieved by moving lens elements within the lens. The lens barrel doesn't move. IF lenses generally focus faster than ordinary lenses.
AL: Aspheric Lens. Special lens elements that improves the optical quality. Particularly valuable in wide angle lenses.
ED: Extra-low Dispersion. Special glass material which helps reduce chromatic aberration. Particularly valuable in tele photo lenses.

Conclusions:

A, F, FA and D FA lenses work on all Pentax bayonet cameras ever produced (exception: A lenses do not work on the MZ-60/ZX-60).

FA J, DA and DA L lenses work on cameras which have Tv and Program auto-exposure mode. Av mode and manual exposure is supported on some of these camera bodies. DA and DA L should only be used on digital cameras with an APS C sized sensor (16 x 24 mm).

M and K lenses work on all cameras except the MZ/ZX-30, MZ/ZX-50 and MZ/ZX-6. They work with limitations on the *ist film camera. They work with stop-down metering on the *ist D series and K series digital SLRs provided that a custom function is set appropriately.

For more information on lens compatibility, please visit our Lens Compatibility Chart over at mosphotos.com.