Firefly – the lightweight Irix series for mobile shooting

TheFireflyversion focuses on low weight and comfortable handling. Its ergonomic focusing ring is rubberized for a secure grip during precise manual focusing.

Three rubber sealshelp protect the mount and focusing mechanism against dust, moisture and accidental splashes.

Blackstone or Firefly – what is the difference?

Both versions share the Irix 15mm f/2.4 optical concept but target different priorities.Fireflyis lighter, with a rubberized focus ring, three seals and a soft pouch.Blackstoneadds all-metal construction, four seals, engraved UV markings and a rigid protective case.

Landscapes, architecture, interiors and night shooting

The 15 mm focal length captures a broad scene, making it well suited to landscapes, architecture and interiors. Thef/2.4maximum aperture expands its usefulness in low light, night landscapes and astrophotography.

Rectilinear 110° – ultra-wide without the typical fisheye look

The angle of view is approximately110°. Its rectilinear design aims to render straight lines more naturally, which is especially important for architecture and interiors.

15 elements in 11 groups and Neutrino Coating

The optical construction uses15 elements in 11 groupsincluding three HR, two ED and two aspherical elements.Neutrino Coatinghelps reduce aberrations, ghosting and flare while maintaining good contrast.

Focus Lock, Infinity Click and hyperfocal scale

Focus Locksecures the chosen focusing position, whileInfinity Clickmakes the infinity position easier to locate by feel. The hyperfocal scale assists with depth-of-field planning.

Focus from 0.28 m and 9 rounded blades

Minimum focusing distance is0.28 mallowing strong foreground emphasis. The diaphragm uses9 rounded bladesfor smoother rendering of out-of-focus areas.

95 mm front filters and 30 × 30 mm gelatin filters

A95 mm front threadaccepts conventional screw-in filters. A rear holder additionally supports30 × 30 mm gelatin filters.

Pentax K – the correct mount for Pentax DSLRs

This version uses thePentax K mountand fits compatible Pentax K-mount DSLRs directly, including full-frame and APS-C bodies.

Adapting the Pentax K version to other mirrorless systems requires a suitable adapter; the electronic functions retained then depend on the adapter and camera body.

The lens focuses manually but has a built-in electronic module.On a compatible body it enables camera-controlled aperture, PASM modes, EXIF recording and focus confirmation.

Key specifications

• series:Firefly
• model:Irix 15mm f/2.4 Firefly
• mount:Pentax K
• focal length:15 mm
• maximum aperture:f/2.4
• type:ultra-wide, rectilinear
• focusing:manual
• angle of view:approx. 110°
• minimum focusing distance:0.28 m
• aperture blades:9, rounded
• optical construction:15 elements / 11 groups
• special elements:3 HR, 2 ED, 2 aspherical
• Focus Lock:yes
• Infinity Click:yes
• filters:95 mm front thread + rear 30 × 30 mm gelatin filters
• sensor format:full frame and APS-C
• Firefly construction:lightweight, rubberized focus ring
• seals:3.
• aperture control:electronically from the camera body
• communication:PASM modes, EXIF recording and focus confirmation.

In the box

• Irix 15mm f/2.4 Firefly for Pentax K
• lens hood
• front lens cap
• 2 rear lens caps
• soft pouch
• original packaging.