[T2.6] I use this lens for Astro and having the indent for infinity focus works great.

[86 mm] I've had this lens for a while now, and it is both truly rectilinear, sharp, and comfortable in the hand.
It's wide! Much more angle and you'll be photographing your feet.

There are electronic contacts for Nikon cameras, and the infinity focus point could be adjusted.
One suggestion I'd make with big, fast lenses, is to consider an ND4 filter so as to keep shutter speeds manageable.

[Full Frame] On a recent outing with my full frame Pentax K1 I had hoped that my current Lens, a 24-70mm zoom lens, would be sufficient to capture everything I wanted but, much to my chagrin, was greatly mistaken. Yes, the individual photos turned out alright but with a super wide angle lens they could have been great. The Lens I really wanted was a super-wide zoom but I was not willing to pay the $2000 price tag which came with it for a lens I seldom use.

Enter the Irix 15mm F/2.4 Firefly. Because it is a prime lens distortion is very well controlled without any curved lines when they should be straight. At F/2.4 it is relatively fast compared to other lenses and I was impressed with my indoors test shots without flash in low light. In outdoor settings the F-stop can be slightly higher for added depth of field without compromising shutter speed.

The manual focus works well and the infinity stop is just soft enough to be noticed without creating additional camera shake when speed is of the essence. I find that the infinity setting works for most situations unless i'm shooting very close in and all my test shots came out clean and crisp. So much for the full frame review.

When mounted on cameras with a C-sized sensor the lens converts into a 22.5mm prime lens with all the afore mentioned attributes. To put it into words everyone can understand: I received two lenses for the price of one.

I give the lens 5 stars all the way for the price I paid and for what I use it.

[T22] This lens, which I bought expressly for night-sky photography, captures a wide swath of the sky. There is distortion of any straight objects in the photo (for example, if a building is shown in the foreground) but that is to be expected with this super-wide lens. Minimal coma in the corners, which is an issue I've had with other wide-angle lenses. And best of all... the infinity setting really IS infinity, and it has a click-stop so I know when I've hit it in the dark. I have this same lens for my Canon 6D (also used for night-sky photography) and the fact that I bought one for my new Pentax should make it clear how much I like this lens.

[T2.6] The IRIX 15mm T2.6 Cine is my go-to for shooting in tight spaces, like car interiors. Its wide-angle capability allows for capturing extensive detail in confined areas, making it ideal for automotive shoots. The T2.6 aperture ensures excellent performance in low-light conditions, crucial for maintaining quality inside vehicles.

Balancing impressively on gimbal rigs, it proves to be a versatile workhorse, capable of handling dynamic shots with stability and clarity. Its durable build adds to its reliability, making it a trustworthy choice for demanding environments.

In short, the IRIX 15mm T2.6 combines wide-angle versatility, low-light proficiency, and rugged durability, standing out as an essential lens for producing high-quality, creative shots in limited spaces. It’s a valuable asset for any video project requiring sharp and expansive visuals in compact settings.

[43.3 mm] I use this coupled with my BMPCC 6K Pro. Like most cinema lenses, this is massive. Be prepared for a workout if you are going handheld. Gearing is very smooth, although a bit stiff if not using a focus wheel. I own all of the cinema lenses and two of the three have decent magnetic hoods, while one does not appear to be as strong. This doesn't affect me as I utilize a matte box. Like most have stated, the lense cover is complete garbage. Pops off for no apparent reason.

[T2.6] Bought this to do wide night astro images... Haven't had a chance to use it for that yet, but in general shooting the quality is great. It can even make for some fun creative shots... I have been shooting with it on a 5DmkIII... I have not had issues with the flairs that some report. I am finding you have to have light hit at just the right angle to cause a flair and a slight recompose is all it takes to remove...

[T2.6] I recently purchased the IRIX 45mm, 150mm, and this 15mm the color from all the lenses seem to match very well. This lens has very little distortion for being such a wide lens.

[9] Great lens for the price, very sharp, fantastic perspective.

[86 mm] Feels solid, but isn't overly heavy. Image quality is great and distortion is reasonable. I shoot it both full frame and S35 and it handles both well.


As others have said, it's true that the lens cap is wonky. Apparently they have a fixed one that you can order separately and hopefully that's what will ship with new copies of the lens.


I use it via an adapter and did have a little trouble finding a friendly one. Fotodiox PL-EF did NOT work. I eventually went with some no-names on eBay that did.