The lens has now been discontinued, replaced in the lineup by the APS-C sized 16-45mm ƒ/4 ED. The lens name bears a long list of standards. SMC stands for Pentax's proprietary ''super multi-coating''; AL represents the lens' use of aspherical lens elements; FA explains the lens is autofocus-enabled, with a digital chip in the lens; and the J designation explains the lens is part of Pentax's budget series of lenses, with a plastic lens mount and no aperture ring.
Small and light, the 18-35mm represents a field of view of approximately 28-53mm in 35mm terms. It uses a full 35mm imaging circle, and thus will work without vignetting on a Pentax film body (though the body must be able to set lens aperture to work properly).
To economize and create a more efficient design, the lens is equipped with a variable aperture; as the zoom extends the focal length, both the smallest and the largest aperture changes. The lens shipped with a large petal-shaped hood. It is widely available used, and is still available online from some retailers for as low as $150.
Review: Pentax 18-35mm f/4-5.6