Pentax
Pentax 28040 FA 21mm F2.4 Limited Lens
★★★★★
Capture Stunning Ultra-Wide PerspectivesExplore the world with the Pentax FA 21mm F2.4 ED Limited DC WR lens, designed for full-frame DSLRs. This ultra-wide-angle single focus lens combines exceptional image quality with a durable build. Featuring HD coating for superior imaging performance and a...
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Overview
Capture Stunning Ultra-Wide Perspectives
Explore the world with the Pentax FA 21mm F2.4 ED Limited DC WR lens, designed for full-frame DSLRs. This ultra-wide-angle single focus lens combines exceptional image quality with a durable build. Featuring HD coating for superior imaging performance and a circular diaphragm for beautiful bokeh, this lens is perfect for landscape, architecture, and creative photography.
- Lens Type: Ultra-Wide-Angle Single Focus Lens
- Focal Length: 21mm
- Aperture: F2.4
- Coating: HD Coating
- Diaphragm: Eight-blade circular diaphragm
- Material: Machined Aluminum Lens Barrel
- Special Features: SP (Super Protect) Coating, Serial Number
- Mount: KAF4 Mount
Key Features
[In-body shake reduction / SRII] The Pentax digital single-lens camera K series is equipped with in-body shake reduction / SR II. Shake reduction is compatible with all mountable lenses. It is possible to reduce the size and weight of the lens.
[Image quality of D FA 21mm F2.4 Limited] When shooting a distant view such as a landscape, a lens realizes sharp and clear depiction across the image field and can express details up to the tips of leaves and branches and the moist air of the morning mist.
[Three policies of Limited Lens] "Essence" Enjoying the act of picture-taking itself " Sensitivity " Depicting an ambience undetectable by simple numerical values "Universariyty" Providing a lens over many years.
[High-definition depiction] A glass-molded aspherical lens with a large apeture of F1.8 and a high-refractive index low-dispersion lens are luxuriously adopted
[DC motor installed] Quiet and smooth autofocus drive is realized by the in-lens motor drive AF.
[HD coating] high-performance multi-coating "HD coating" minimizes the occurrence of ghosts and flares effectively under severe shooting conditions such as backlight
[SP (Super Protect) coating] Pentax's original special coating that provides superior performace in repelling water and oil is used on the front surface of the lens. This coating not only prevents adhesion of dust, water drops, oils, and other substances, but it also makes it easy to wipe off objects that adhere to the lens.
[Aluminum machined body] Emphasis is placed on the high-quality design and texture when picked up, and the exterior parts are molded one by one by machined aluminum.
AF4 mount adopted] A KAF4 mount that uses an electromagnetic diaphragm is used. Compatible models are the latest for PENTAX K-3 Mark III, K-3 II, K-3, KP, K-70, K-50, K-S2, K-S1, K-1 Mark II, and K-1. Please update to the firmware of.
[What's in the box] Dedicated lens cap O-LW74A, lens mount cap K, lens case P80-150
Specifications
Mount Type
KAF4 (Electromagnetic Diaphragm)
Focal Length
21mm
Aperture
F2.4 (Large aperture of F1.8 for aspherical lens)
Lens Elements
Glass-molded aspherical lens, High-refractive index low-dispersion lens
Autofocus
DC motor installed
Coating
HD coating, SP (Super Protect) coating
Body Material
Aluminum machined body
Included Accessories
Dedicated lens cap O-LW74A, lens mount cap K, lens case P80-150
Compatible Cameras
PENTAX K-3 Mark III, K-3 II, K-3, KP, K-70, K-50, K-S2, K-S1, K-1 Mark II, K-1 (with firmware update)
Pros & Cons
👍 Pros
- Delivers sharp and clear depiction across the entire image field, ideal for capturing distant landscapes
- Excels at expressing fine details, such as the tips of leaves and branches or the subtle mist in the air
- Equipped with a DC motor for quiet and smooth autofocus, minimizing distractions during shooting
- Features HD coating, a high-performance multi-coating that effectively reduces ghosts and flares in challenging lighting
- Includes SP (Super Protect) coating on the front surface, which repels water, oil, and dust for easier cleaning and maintenance
- Constructed with an aluminum machined body, offering a high-quality design and premium tactile feel
- Adopts a KAF4 mount with an electromagnetic diaphragm, ensuring compatibility with the latest Pentax K-series digital SLRs
- Designed according to "Limited Lens" policies, emphasizing the joy of picture-taking and capturing ambience
- Comes with essential accessories including a dedicated lens cap, lens mount cap, and lens case for immediate protection
- Incorporates a glass-molded aspherical lens and high-refractive index low-dispersion lens for exceptional image quality
👎 Cons
- Requires a firmware update for certain Pentax K-series models to ensure full compatibility and functionality
- Only compatible with KAF4 mount Pentax cameras, which might limit its use to a specific range of bodies
- The F2.4 aperture, while suitable for many situations, may not be fast enough for extreme low-light photography compared to wider aperture primes
- Specific weight and dimensions are not provided, making it difficult to assess its overall bulk and balance on a camera body
- The focus on "Essence" and "Sensitivity" might not fully satisfy users who strictly prioritize measurable sharpness and technical perfection over artistic qualities
Frequently Asked Questions
What kind of autofocus system does the Pentax 28040 FA 21mm F2.4 Limited Lens use?
This lens utilizes an in-lens DC motor drive for autofocus, which provides quiet and smooth operation.
Does this lens offer protection against environmental elements like water and oil?
Yes, it features Pentax's original SP (Super Protect) coating on the front surface, which offers superior performance in repelling water and oil and makes cleaning easy.
What is the purpose of the HD coating on this lens?
The HD coating is a high-performance multi-coating designed to effectively minimize the occurrence of ghosts and flares, even in challenging backlighting conditions.
What materials are used for the construction of the lens body?
The lens features an aluminum machined body, with exterior parts molded individually from machined aluminum, emphasizing high-quality design and texture.
Which Pentax camera models are compatible with this lens?
This lens uses a KAF4 mount and is compatible with the latest PENTAX K-3 Mark III, K-3 II, K-3, KP, K-70, K-50, K-S2, K-S1, K-1 Mark II, and K-1 models, requiring a firmware update for some.
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