The silver HD Pentax DA 20-40mm f/2.8-4 ED Limited DC WR Lens from Pentax is a high performance standard length zoom lens for K-mount APS-C cameras. Its 35mm focal length equivalency is 30.5-61.5mm providing a versatile and practical range for wide-angle to standard length shooting. It is the first zoom lens in the Pentax Limited Series line and brings with it a durable, weather-sealed body, HD lens coating and an optical design consisting of one ED element and one super-low dispersion element.

The f/2.8-4 maximum aperture enables effective low light shooting and, at the wide-angle end, control over its shallow depth of field for images that place sharp focus on the subject with a pleasing out of focus background. An in-lens direct current (DC) focus motor provides smooth and quiet autofocus action and its Quick-Shift Focus System enables rapid shift from autofocus to manual focus mode.

The lens barrel and the included hood are made from high-grade aluminum alloy, distance and depth of field scales are clearly marked on the barrel and a smooth rotating, knurled ring provides manual focus control. SP (Super Protect) coating on the front and rear lens elements repels dust, water and grease to help maintain peak performance.

Pentax K Mount    30.5-61.5mm (35mm Equivalent)    Aperture Range: f/2.8-32    ED and Super-Low Dispersion Elements    High-Grade Multi-Layer HD Coating    Weather-Resistant Seals and SP Coating    Smooth & Quiet DC Auto Focus Motor    Quick-Shift Focus System    Rounded Nine-Blade Diaphragm    First Limited Series Zoom Lens

With its 2x zoom coverage of 20-40mm, this lens offers focal length coverage from 30.5 to 61.5mm in the 35mm format when mounted on a PENTAX K-series DSLR. This covers a practical set of frequently used focal lengths and is ideal as a versatile everyday lens. Its maximum aperture of f/2.8 at the wide-angle end of the zoom is effective in low light and provides shallow depth of field focus.

This lens has been treated with the PENTAX-developed HD coating, a high grade, multi-layer coating that reduces unwanted reflection, allowing the user to capture high-contrast images free of flare and ghosting.

Shoot discreetly with in-lens, direct current (DC) Auto Focus motor operation for smooth & quiet performance.

The Quick-Shift Focus System allows instant switching from autofocus to manual focus operation.

With seven special seals to prevent intrusion of water, moisture and dust, this is the first lens of the "Limited" series to feature the PENTAX-original weather-resistant construction. With a handsome and durable aluminum alloy barrel and weather-sealing, this lens is able to perform in almost any shooting condition.

The PENTAX SP (Super Protect) coating on the front and rear lens elements repels dust, water and grease to keep your lens clean and your images sharp.

The ED (Extra-low Dispersion) glass and a super-low dispersion glass element in this lens' optics deliver clear, high resolution imagery with edge-to-edge sharpness, throughout the entire zoom range.

Enhanced with a rounded nine-blade diaphragm at the wide apertures for optimal optical performance and gorgeous bokeh effects.

Related Questions and Answers

Q: 1. How will this lens behave on a FF body like the K1?

A: The Pentax HD Pentax DA* 11-18mm f/2.8 ED DC AW Lens is designed for cropped sensor cameras only. The Pentax K-1 does have a cropped sensor mode so you could use this lens. You will only be using a small section of the sensor and will get a small file size.

Q: 2. Product description mentions an “optional heating device”. What would that be?

A: An example of a dew heater for the Pentax HD Pentax DA* 11-18mm f/2.8 ED DC AW Lens is this Neewer 15.7" USB Lens Heater for Camera & Telescope Lenses. https://bit.ly/3OaLkNn

Q: 3. Will this lens work with a Pentax K10 ?

A: Yes, in fact, all the lenses that I used on my K10 work just fine on my K5 and K3. This particular lens is one of my favorites. It is really sharp, has great color and even does macro - you can't go wrong.

Q: 4. Will it cause vignetting on the Pentax K-1?

A: On a full frame K-1, this APS-C lens will vignette.

Q: 5. Does this lens work with a Novoflex Pentax K to Sony E body adapter? Does it have the aperture mecanism of other Pentax K ?

A: The Pentax HD PENTAX-D FA 21mm f/2.4ED Limited DC WR Lens can be used on a Sony E-mount camera with the Novoflex Adapter for Pentax K Lens to Sony NEX Camera, BH #NOAPKSNEX. However, the lens will not autofocus, and the aperture has to be set with the aperture ring on the adapter. The Monster Adapter LA-KE1 Magic Ring Pentax K Lens to Sony E-Mount Camera Adapter, BH #MOPKSEA, supports autofocus and camera-to-lens communication.

Q: 6. Will this work with the auto-focus on my Pentax K-3?

A: Yes.

Q: 7. Is the lens barrel (including the extension), made of metal or composite (plastic)?

A: The lens barrel is a combination of poly carbonate and metal.

Q: 8. Is this lens brand new?

A: Yes, this is a brand-new lens.

Q: 9. Does this lens come with front and rear caps for storage protection?

A: The Pentax HD Pentax DA 35mm f/2.8 Macro Limited Lens (Black) includes front and rear lens caps.

Q: 10. Is this lens sealed and water resistant?

A: Unfortunately, the Pentax 35mm f/2.8 macro lens is not a WR lens, so is not weather sealed. The only macro lens from Pentaxt that is currently a WR lens would be the Pentax 100mm f/2.8 WR Macro lens (B&H # PE10028MDFAW).