Irix 15mm f/2.4 – Review by Dionisis Eleftheriadis

Irix 15mm f/2.4 is an ultra-wide lens, with amazing optics and built quality overall. It is mainly used for landscapes, architecture, and astrophotography shots.

I am an astrophotographer myself and the Irix 15 mm Firefly was the perfect addition to my gear, as in astrophotography you need to capture as much light as possible in the dark sceneries.


Aperture F/2.4

To start with, I will give my personal experience and overall conclusion about how this lens works in low light conditions, sharpness, and distortion.

The fact that this lens is wide is an amazing benefit for every photographer, that just wants to shoot a wide view, but the thing that it is an F/2.4 lens allows you to capture much more light from our beloved sky, the nebulae, the stars, and of course the Milky Way. When I first went on the “ field” with my new lens and started to shoot I couldn’t believe my eyes the amount of detail I could capture with this lens. I use a star tracker for my shots to get better details overall, but since Irix released the Firefly/Blackstone series, nightscape became easier. Just find your subject, set your settings accordingly, and your good to go. Leave everything to the lens and enjoy the stars. That is all about the great aperture system that the Irix lens has and the things you can achieve.



We are talking about an ULTRA-wide lens. So normally everyone will assume that it has a great amount of distortion. Fortunately, it has only 2% distortion which is not visible. Shooting large objects which are at the edges of the frame is always a challenge for this kind of lenses, but with the innovative system, Irix really made the difference. So shoot wide without any worry about it.


Sharpness and color abilities

About sharpness. Well, I can say for sure according to nightscape this lens is extremely sharp in the center and as you go wider to the edges it loses very little of this sharpness. But consider it stopping down 1 or 2 stops and you will get the best result. Don’t forget it is a really “bright” lens and that gives you the chance to stop down a little. I find the sweet spot between F/3.2 and F/4 in astrophotography, where the amount of light that reaches your sensor is critical. All that if you use a sturdy tripod and not a star tracker. If you are on the tracker, you can use any f/stop you like to compose your image and the stunning shot you imagine.

Another thing that draws my attention about this ultra-wide lens is the coating on the glass. It is the NEUTRINO COATING that offers these great colors. Honestly, I love how it performs in low-light conditions and daylight shots.


The focus ring and lock

Any astrophotographer like myself knows that shooting at night is extremely difficult. In terms of focus, you need to be precise otherwise your shot is ruined. Irix has a new element on this lens that gives you the ability to focus in infinity by just “feeling” the focus ring that is set in infinity, without worrying. It just clips in infinity and you are good to go to shoot some really sharp and pinpoint stars.


Rear slot gelatin filters

Shooting on extremely bright days or facing the sun is a real pain for photographers. Using filters such as an ND, polarizing filters, and graduated makes your life easier and creates an amazing shot. But one thing that I loved about this lens is that you can insert some ND gelatin filters, so tiny and thin in the back of the lens. There is a variety of stops you can use such as ND 4, ND 8, and ND 16. For me, it is a game-changer, this feature as it is really handy, and does the job.


Conclusion and overall thoughts

When I was looking for a wide lens in the market I was very skeptical about getting that wide. But it turned out handy. Shooting at night is a real challenge, so you need the best equipment. Having the Irix 15mm F/2.4 in your bag is the best thing you can do if you like shooting wide and in low light conditions. I love the premium built of this lens, the extra new features that it has in comparison to the other lenses in the market. It is very lightweight for an ultra-wide lens. Once you use it you will find that the aperture is your best friend at the night.

I love the thing that I don’t have to worry about focusing in the night to get pinpoint stars anymore with that lens. Another thing is that the built quality is that good that I tested one day in heavy rain for a timelapse of my own. It is weather-sealed, an attribute that may concern a lot of us.

I would like it to be a little bit sharper at f/2.4 to get the most out of it, but it’s not a big deal. One thing you need to know is that the front element is really wide(95mm thread) so you need to be aware that using a circular filter of any kind will cost you. Otherwise, you can use the amazing feature that Irix offers you with the rear slot filters, which I am excited about.

Overall I am very happy with that lens, I would recommend it to everyone who wants to start landscape or astrophotography, and looking for an amazing lens such as this one.


You can see more of Dionisis’s work here: 


and learn more about Irix 15 mm f/2.4 lens:

Irix 15mm f/2.4


arrow_back Back to list