Distinguished by its refined physical construction, the 11mm f/4 Blackstone Lens from Irix is an ultra-wide prime designed for Canon EF-mount DSLRs. As a rectilinear lens, the advanced optical layout makes use of aspherical, extra-low dispersion, and high-refractive index elements to control distortion and aberrations for accurate, and sharp rendering with a high degree of clarity and color accuracy. Additionally, a Neutrino coating has also been applied to the lens to control flare and ghosting for improved contrast when working in strong lighting conditions.

Beyond its optical assets, this 11mm f/4 lens also sports a manual focus design for fine-tuned control, and incorporates a unique positive focus lock to secure the focusing position at any point for consistent, repeatable shooting. As the Blackstone version of this focal length, this lens is also distinguished by an aluminum and magnesium alloy exterior, engraved lens markings with fluorescent UV paint for high visibility, and extensive weather-sealing about the lens to permit working in harsh environments.

Canon EF-Mount/Full-Frame Format    Aperture Range: f/4 to f/22    Three Aspherical Elements    Two ED and Four HR Elements    Neutrino Coating    Manual Focus Design with Focus Lock    UV Fluorescent Engraved Markings    Depth of Field and Focus Distance Scales    Weather-Sealed Magnesium Alloy Housing    Rounded Nine-Blade Diaphragm

The Blackstone version of the 11mm f/4 lens features a durable aluminum and magnesium alloy housing and weather-resistant exterior along with inner seals, and an extra seal at the front element, to protect against dust and moisture intrusion. The metal exterior also distinguishes itself with an anti-scratch finish, and sports engraved focus distance and depth of field scales with fluorescent UV paint for high visibility when working in low-light conditions.

Ultra wide-angle prime designed for full-frame Canon EF-mount DSLRs, this lens can also be used on APS-C models where it provides a 17.6mm equivalent focal length.

Three aspherical, four high-refractive index, and two extra-low dispersion elements are featured within the optical design to limit both spherical and chromatic aberrations, as well as color fringing and distortion, for improved clarity, sharpness, and even illumination.

A Neutrino coating has been applied to limit lens flare and ghosting for improved contrast and color fidelity.

Manual focus designed is benefitted by a positive focus lock mechanism to secure your focus position at any point to limit unwanted shifting of focus.

A hard click stop indicates the infinity position on the focus ring for easy use in low-visibility conditions.

Large depth of field scale benefits using hyperfocal and pre-focus techniques.

Built-in petal-shaped lens hood blocks stray light in order to reduce lens flare, and also protects the front element of the lens.

Rear of the lens accepts 30 x 30mm cut gel filters.

Rounded nine-blade diaphragm contributes to smooth bokeh.

Includes complimentary additional rear lens cap.

Related Questions and Answers

Q: 1. What mm size UV protective filter fits this Irix 11mm Blackstone Lens?

A: Due the shape of the front element on the IRIX 11mm f/4 Blackstone Lens for Canon EF, it doesn't accept screw in UV protective filters.

Q: 2. Does this lens work on the FTZ adapter for Nikon Z cameras?

A: The IRIX 11mm f/4 Firefly Lens for Nikon F is a manual focus and exposure lens that is compatible with Nikon Z cameras with the FTZ adapter.

Q: 3. (Please ignore or delete my previous question about the difference between the FireFly and Blackstone iterations of this lens -- it is answered in the Overview -Duh! - My bad.) Are the FireFly and Blackstone editions identical in terms of image quality? Thank you!

A: yes Mark the firefly and the blackstone are identical in image quality. The only difference is between them is that the blackstone is fully weather sealed.

Q: 4. How is the iris controlled on a Nikon F-mount camera? Is there a 'G' style control lever? Or is it purely electronically controlled?

A: The aperture is electronically controlled.

Q: 5. Can we get ND filter for this lense ?

A: Yes, But a adapters are needed. Please look into the following item. Cokin Universal X-Pro Series Filter Holder Adapter Ring https://bhpho.to/37clouY Cokin X-Pro Series Filter Holder https://bhpho.to/3C9fTLZ

Q: 6. is it compatible with Blackmagic Pocket Cinema 6K Pro?

A: Yes, IRIX 11mm f/4 Firefly Lens for Canon EF is compatible with Blackmagic Design Pocket Cinema Camera 6K Pro. Both products are desing with Canon EF mount.

Q: 7. Can the aperture be controlled with a dead adater like the FotodioX Pro TLT ROKR Tilt-Shift Adapter for Nikon F Lens to Sony E ?

A: The aperture in the IRIX 11mm f/4 Firefly Lens is only controlled electronically. So the Fotodiox tilt/shift adapter would not be able to control the aperture.

Q: 8. Is there an 150mm filter holder for this lens

A: Not that I know of that we sell, there may be some coming soon from Nisi, Lee, Fotodiox, etc..

Q: 9. Anyone using this with a c100 mkii? If so, thoughts?

A: The IRIX 11mm f/4 Blackstone Lens for Canon EF is an excellent choice for someone interested in a super wide angle rectilinear lens for the C100 Mk II Digital Cinema Camera. The rectilinear design limits image distortion and the lens uses a positive lock mechanism that will make it easier to pull focus consistently and accurately.

Q: 10. Is this a fisheye lenses? Thanks

A: The IRIX 11mm f/4 Firefly Lens for Canon EF is an ultra-wide-angle lens, but it's not technically a fisheye lens--it doesn't create a circular image and it has been designed to minimize some of the distortion inherent in a lens with a focal length this wide.