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IRIX 11mm f/4.0 Firefly Lens for Pentax DSLR Cameras - Manual Focus

SKU: IRXF114PX MFR: IL-11FF-PK
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Key Features

  • Capture stunning, expansive scenes with the Irix 11mm f/4 Firefly lens on your Pentax DSLR.
  • Achieve exceptional image quality with this lens's 16 elements in 10 groups design.
  • The manual focus on this Irix lens allows precise control for landscape and architecture.
  • With a wide 126° angle of view, this 11mm lens is perfect for immersive photography.
  • Enjoy sharp, clear images thanks to aspherical and ED glass elements in this prime lens.
  • The Irix Firefly lens is lightweight and robust, ideal for travel and outdoor adventures.
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Special Order?Estimated to Ship: 08/20/2025
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IRIX 11MM F/4.0 FIREFLY Specifications

General

General

Jump to...
  • Lens Mount

    Pentax K

  • Lens Format

    Full Frame

  • Lens Type

    Ultra-Wide Angle

  • Compatibility

    Pentax K-1, Pentax K-1 Mark II

  • Lens Series

    Irix Firefly Series

  • Special Features

    Aspherical

  • Kit Style

    Base

  • MPN

    IL-11FF-PK

  • Color

    Black

  • Focus Type

    Manual Focus

  • Closest Focus Distance

    10.83" / 27.5cm

  • Distance Information

    No

  • Built-In Motor

    No

  • Fixed Focal Length

    11mm

  • Maximum Aperture

    f/4

  • Filter Size

    No Thread

  • Angle Of View

    126°

  • Minimum Aperture

    f/22

  • Aspherical Elements

    Yes

  • ED Glass Elements

    Yes

Features

Jump to...
  • Image Stabilization Type

    No

  • Tripod Collar

    No

  • Waterproof / Water Resistant

    No

  • Dust Resistant

    No

Construction

Jump to...
  • Lens Elements / Groups

    16 Elements in 10 Groups

  • Diaphragm Blades

    9

  • Weight

    1.61lb / 730g

  • Dimensions

    4.65 x 4.06" / 118 x 103mm

  • UPC Code

    7640172190340

4 Accessories for IRIX 11mm f/4.0 Firefly Lens for Pentax DSLR Cameras - Manual Focus

  • All Accessories (4)
  • Cleaning Accessories (2)
  • Cap Leash (1)
  • Bags & Cases (1)

Designed For Use With:

  • Pentax K-1 Mark II
  • Pentax K-1

Compatible With Restrictions:*

* If using a APS-C Lens on a Full Frame Camera OR Full-Frame Lens on a APS-C Camera then Image sensor will be narrowed down to APS-C size.

  • Pentax K-01
  • Pentax K-2000
  • Pentax K-3
  • Pentax K-3 II
  • Pentax K-30
  • Pentax K-5 IIs
  • Pentax K-50
  • Pentax K-500
  • Pentax K-7
  • Pentax K-70
  • Pentax KP
  • Pentax K-S1
  • Pentax K-S2

Need Help?

For any questions about compatibility with this product, call us at 800-223-2500 or you can email us any time.

Models
IRIX 11mm f/4.0 Firefly Lens for Pentax DSLR Cameras - Manual Focus
$449.00

Special Order

Generally ships in 7-14 days, subject to availability

IRIX 15mm f/2.4 Firefly Lens for Pentax K

SKU: IRXF1524PX

MFR: IL-15FF-PK

$379.00

In Stock

CompatibilityPentax K-1, Pentax K-1 Mark IIPentax K-1, Pentax K-1 Mark IIPentax K-1, Pentax K-1 Mark II
Special FeaturesAsphericalAsphericalAspherical
Kit StyleBaseBaseBase
Lens TypeUltra-Wide AngleUltra-Wide AngleUltra-Wide Angle
Filter SizeNo ThreadNo Thread95mm
Fixed Focal Length11mm11mm15mm
Lens MountPentax KPentax KPentax K
Maximum Aperturef/4f/4f/2.4

About IRIX 11MM F/4.0 FIREFLY

Irix 11mm Blackstone

a minimal distortion wide angle lens

The Irix 11mm lens is an extremely wide Full Frame rectilinear lens with a 126° angle of view. 4 high refractive lenses, 2 ED lenses and 3 aspherical lenses guarantee minimal distortion, as low as 3.13%, making our 11mm f/4.0 lens absolutely unique in its class.

a lightweight option with no optical compromises

a lightweight option with no optical compromises

The Irix 11mm Firefly lens offers the same optical performance and high quality mechanism as our Blackstone, but its ultra lightweight construction makes it the perfect choice for hikers, travellers, or anyone who simply likes to pack light. The ergonomic, anti-slip, rubber coated focus ring makes for a practical, user-friendly lens. This lightweight option is ideal for on the go photography, without any compromise on optical quality.

The Irix 11mm f/4.0 Blackstone is compatible with full frame and APS-C sensors. As a fixed focal lens, it has a higher technical quality than wide angle zoom lenses and it will oblige you to look for the best frame for each photograph. You will be in absolute control of your own work. You will have an angle of view of 126° to work with.

Blackstone

Blackstone

  • durable Al-Mg body
  • UV light reactive markings

Firefly

Firefly

  • ultra-lightweight construction
  • ergonomic focus ring

innovative technology encased in a smart design

Torn between smart technology and a classical design? With our Irix Blackstone 11mm f/4 lens, you can have both. We have matched timeless design decisions with maximum functionality to offer you the perfect piece of durable technology. The solid aluminium and magnesium body ensures foolproof lens protection, even in the most extreme situations. Easy operation is achieved in all lighting conditions thanks to our engraved fluorescent markings, just one of our many ingenious, photographer-friendly developments.

extreme weather resistance

extreme weather resistance

We know how important it is to protect your gear. Our Irix lenses are made with phenomenal precision. Each Irix lens is equipped with a weather sealed construction which protects the interior against dust and moisture. Thanks to inner seals, our lenses are also protected from accidental water splashes. No matter the journey, you can be confident that our weather sealed lenses will offer you maximum resistance to the extremes."

Irix 11mm Comparison

Key Features

  • Capture stunning, expansive scenes with the Irix 11mm f/4 Firefly lens on your Pentax DSLR.
  • Achieve exceptional image quality with this lens's 16 elements in 10 groups design.
  • The manual focus on this Irix lens allows precise control for landscape and architecture.
  • With a wide 126° angle of view, this 11mm lens is perfect for immersive photography.
  • Enjoy sharp, clear images thanks to aspherical and ED glass elements in this prime lens.
  • The Irix Firefly lens is lightweight and robust, ideal for travel and outdoor adventures.

What's in the box:

  • IRIX 11mm f/4.0 Firefly Lens
  • Built-In Lens Hood
  • Soft Pouch
  • IRIX 2 Year Warranty