Обзор irix 15mm f / 2.4 firefly

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Recommendations

This is a great 15mm lens at a bargain price and much nicer than anything else I’ve ever seen out of Korea. If you’re in the market for a fixed 15mm ultra ultrawide, this is probably your best buy.

Filters

Protection

I’d use a 95mm B+W MRC 010 UV filter to protect this lens.

A better filter for twice the price is the 95mm Hoya EVO UV. It has special dirt, dust and smudge resistant multicoatings to stay cleaner longer.

Grads and ND

I use Tiffen HT grads because they are the only truly neutral NDs and grads I’ve used, they are multicoated and thin enough not to vignette.

Polarizers

; the sky’s natural polarization will appear as a dark band in the sky.

Where to get yours

I’d get it at Adorama, at Amazon or at B&H.

This all-content, junk-free website’s biggest source of support is when you use those or any of when you get anything, regardless of the country in which you live. Irix does not seal its boxes in any way, so never buy at retail or any other source not on since you’ll have no way of knowing if you’re missing accessories, getting a defective, damaged, returned, store demo or used lens. I use the stores I do because they ship from secure remote warehouses where no one gets to touch your new camera before you do. Buy only from the for the best prices, service, return policies and selection.

Thanks for helping me help you!

Ken, Mrs. Rockwell, Ryan and Katie.

Build Quality

With a durable body made of aluminum and magnesium, this lens looks and feels like it can take a beating (not that you’d really want to do that). The lens elements are clearly machined with precision; everything fits nice and snug together and move smoothly when adjusting focus on the lens. The lens is weather sealed, in addition to the durable body, by four interior rubber seals that protect both the camera mount and focusing mechanism against dust and moisture (water resistant, not waterproof). The lens is built for the use of both 95mm screw-in filters on the front of the lens and also gelatin filters which slide in a small slot at the back of the lens. For the Blackstone, the premium version, the engraved lens markings are fluorescent which makes it that much easier to operate and make adjustments in low light situations.

A visual depiction of the location of each interior rubber seal.

Flare and Ghosting

The special neutrino coating is one that Irix developed to help attain better contrast while keeping color aberration, ghosting, and flaring to a minimum. From what I’ve shot with this lens so far, what I have noticed as far as flaring and ghosting seems to be consistent with other reputable, high-quality lenses. I still got flare and ghosts in some of my shots, but they were still very clean and in many cases as good as one could hope for. With nine aperture blades your sunstars will have 18 points, which for me is a plus as I like how that looks. Obviously any flaring or ghosting will be dependent on your shoot conditions and the composition itself. The image below is one that had the most noticeable elements, which is why it is included in this review. As you can see, as far as flaring and ghosts go, it’s still pretty clean.

15mm • ƒ/22 • 1/80s • ISO 100

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Irix 11mm f/4 Firefly Verdict

What an exciting lens the Irix 11mm f/4 Firefly is. It opens up a whole new world of creative possibilities in a well-made, well-designed package that delivers the image quality. It will not be for everybody, perhaps because of the ultra-wide style of the images, or maybe because of difficulties using the manual focus system, but if the lens appeals to the individual photographer’s creativity then it will be a rewarding experience.

Irix 11mm f/4 Firefly Pros

Very good sharpness
CA well corrected centrally
Widest rectilinear lens available
Very little chance of flare
Moisture and dust resistance
Well priced

Irix 11mm f/4 Firefly Cons

Some edge CA
Manual focusing via the camera screen very difficult

Features4/5

Handling4.5/5

Performance4/5

Value4.5/5

Overall Verdict

With thanks to CliftonCameras who provided the Canon EOS 5DS R used for testing.

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Image Quality

Let’s be honest, this is usually what makes or breaks it for a lens. I’ve taken this lens into several various situations both during the day and at night and I am pretty solidly happy with the results I’ve been able to get from using it.

Sharpness

This lens actually holds its own very well with image sharpness. I have been incredibly happy with the sharpness across the entire frame. Below is an example of a square cropped image and a sample of the image zoomed in at 100 percent. You can see that edges retain great shape without too much issue.

This image below is a sample taken at 100 percent of the top right corner of the image. You can see that we lose a bit of sharpness in the corners, but not a whole lot.

Vignetting

The vignetting really isn’t that bad, actually. To the point where I was still quite happy with the shots straight out of the camera, but when you apply their lens profile to correct the image, then the vignetting virtually disappears.

Contrast

This is one area where this lens really does very, very well. Not only does it preserve the image with ideal levels for contrast, but the color translation is solid. It’s not often where what you see is what you’ll get, but this lens comes pretty damn close to delivering just that.

Overall, concerning image quality, I was quite impressed with how each image turned out. From maintaining image structure with very little distortion to color retention and sharpness, this lens really holds its own against other lenses in similar classes.

15mm • ƒ/6.3 • 5s • ISO 50

15mm • ƒ/16 • 6s • ISO 100

Low Light Handling

Granted, there are other prime lenses out there that have wider apertures at similar focal lengths. But I was very happy with what I was able to crank out with this lens opened up to f/2.5 while sticking to an ISO range of 1,600 to 6,400 for galaxy shots.

The wider aperture is great and as long as I didn’t set up too close to my foreground then I didn’t have to worry too much about focus stacking my shots even wide open. For low light work my favorite feature, by far, is the ability to lock the focus ring. I was able to set my focus for landscape work as soon as I got on location, lock it, and for the rest of the entire evening I didn’t have to worry about resetting my focus even once. It was awesome; I could just move from shot, to shot, to shot.

15mm • ƒ/2.5 • 1/2s • ISO 400

15mm • ƒ/2.5 • 30s • ISO 3200

Bokeh

I wasn’t quite sure what to expect here. Most of my uses for wide-angle lenses don’t involve getting very close to any of my subjects, so I almost forgot to go have some fun with close-ups at a wide open aperture. But I have to say, I am fairly impressed. The bokeh is smooth without any odd patterns or textures. Because the focus ring is so long in turn radius, it is pretty easy to compose your shot and then dial in your focus with precision. Especially since you have to be incredibly close to your subjects at 15mm in order to see much in the way of bokeh anyway.

15mm • ƒ/2.8 • 1/10s • ISO 1600

15mm • ƒ/2.8 • 1/250s • ISO 1600

Focusing

Although the lens was designed for electronic control of the aperture settings, focusing for this one is all manual. Focusing is very smooth. The focus ring has a very crisp and smooth feel to it whenever you adjust focus. The distance between the minimum focal range of 0.28 meters (0.92 feet) and infinite focus is quite large along the ring, making it much easier to set and refine your focus.

One of my favorite features of this lens is what Irix calls the «infinity click.» When you adjust the focus ring to set the lens on the «infinity» position, there is a noticeable click when the ring hits that position. This makes it very easy to find or reset your infinity focus even when you have difficulty seeing the markings on the outside of the lens or even looking through the viewfinder. The addition of the focus lock ring is particularly helpful when you need to set focus once and not have to worry about bumping your camera which might adjust your focus on other lenses. I found this to be helpful when shooting in Zion National Park, particularly when I was hiking up the Narrows. I was able to set my gear once, take a shot, and then hike to my next shoot spot without having to worry about whether the lens was still in focus or not.

The focus lock ring is found just above the focus ring, with a symbol depicting to turn left to lock focus and turn right to unlock the focus.

Introduction

B&H Photo — Video — Pro Audio

I buy only from . I can’t vouch for below.

This manual-focus Irix 15mm f/2.4 lens has superb optics, easily the equal or better than the larger, older and more expensive Zeiss 15mm f/2.8.

Irix 15mm f/2.4, Blackstone version for Canon. bigger.

Blackstone (metal) or Firefly (plastic) outsides?

You can get the same great optics in either metal or plastic outer barrels as the Blackstone or Firefly versions.

I’m reviewing the 15mm f/2.4 Blackstone for Canon, which comes in a metal barrel as shown here. The all-metal Blackstone version is very nice, just like a Zeiss 15mm f/2.8

The same optics also come with a plastic outer barrel, called the 15mm f/2.4 Firefly.

The Firefly version (not shown here) has the same optics, the same aluminium internal mechanics and metal mount, but has plastic outsides with a rubber focus ring with a raised bar to let you focus by feel in the dark and has a different case— and weighs less and sells for only 2/3 the price.

Which you prefer depends on your budget for money and for weight; it’s the same lens inside.

If weight isn’t a concern, see Is It Worth It.

Sample Images

Desert Palms, 13 May 2017. Canon 5DSR, Irix 15mm f/2.4, f/5.6 at 30 seconds at ISO 100. bigger, or full-resolution file to explore on your computer.

The palm trunks and fronds look soft in many places because there was a lot of wind; they were blowing all over the place!

See the tiny white dashes in the sky in the full-resolution file? Those are stars which moved and made short trails in 30 seconds!

Spanish Home, 13 May 2017. Canon 5DSR, Irix 15mm f/2.4, f/2.4 at 1 second at ISO 100. bigger, or camera-original file to explore on your computer.

Look at the white couch on the left. See the diagonal stripes in the camera-original file? Those are aliases excited by the fabric and extreme sharpness of this lens — and I shot this wide-open at f/2.4! It’s a plain white couch.

Irix 15mm f/2.4 Performance

So, does the technical quality of the lens match its quality feel?

Central sharpness is excellent from f/2.4 all the way through to f/16. It remains very good at f/22 and makes the inclusion of that very small aperture worthwhile. It means we can usefully take advantage of maximum depth of field when necessary.

The edge results are of course not as good at the close test target distances as they are out in the field. Field curvature makes the shooting of a flat test target more difficult for an ultra-wide lens to shine. As a result, f/2.4 and f/4 are relatively soft at the edges, f/5.6 improves to a good level, but it is not till f/8 that sharpness becomes very good. This becomes excellent by f/11 and remains very good at f/16 and f/22. In any event, this is a much better performance than 15mm lenses tried in the past.

MTF

How to read our charts

The blue column represents readings from the centre of the picture frame at the various apertures and the green is from the edges.
The scale on the left side is an indication of actual image resolution as LW/PH and is described in detail above. The taller the column, the better the lens performance.
For this review, the lens was tested on a Canon EOS 6D using Imatest.

Centrally, the CA figures are as close to zero as we could possibly expect, which is outstanding. At the edges, correction is remarkable for such an ultra-wide lens and any residual CA could be easily tackled in software. As it stands, this will probably not be necessary for most shots.

How to read our charts

Chromatic aberration is the lens’ inability to focus on the sensor or film all colours of visible light at the same point. Severe chromatic aberration gives a noticeable fringing or a halo effect around sharp edges within the picture. It can be cured in software.
Apochromatic lenses have special lens elements (aspheric, extra-low dispersion etc) to minimize the problem, hence they usually cost more.
For this review, the lens was tested on a Canon EOS 6D using Imatest.

The flare resistance is just about complete and even when shooting right into the light there is no noticeable reduction in contrast. Images remain crisp and there are no spurious artefacts.

Distortion is well held at -2.07% barrelling, which is very reasonable for such a wide lens. Again, for most shots, I would just leave this as it is, although software correction is always possible if required.

The nine-bladed diaphragm, with rounded blades, gives a very pleasant appearance to the bokeh of the lens. It is easily possible to have out of focus areas in even a 15mm lens, especially where the main subject is very close. The gradation of the bokeh is smooth and satisfying to the eye.

So, to answer the opening question, yes, the Irix 15mm f/2.4 Blackstone lives up to its quality feel when the images are examined, and acquits itself very well indeed.

Usage

f/2.4?

This lens is f/2.4, which is a half-stop faster than f/2.8.

Since Nikon and Canon cameras usually are set to work in third stops, sometimes they will show this lens as f/2.5, which is a third stop faster than f/2.8.

Potato, potatoe. Ignore this; f/2.5 is the same as f/2.4 as far as photography is concerned.

Lens Hood

The hood can mount four ways, but only two ways are correct.

The other two will be 90º off and you’ll have dark left and right image sides, with a square image in the center.

Be sure the hood is mounted so the long parts of the hood are on top and bottom, not left and right.

Focus

I focus manual ultra-ultrawide SLR lenses by scale: I guess at the distance, and set it on the focus ring. It’s usually more accurate than using focus aids through an SLR’s viewfinder.

Live View at f/2.4 is the most accurate.

Irix 11mm f/4 Sample Photos

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Value For Money

The Irix 11mm f/4 Firefly lens is priced at around €635, with really nothing else to compare it with. There are 10mm and 11mm rectilinear lenses, but all for APS-C format.

The nearest competitors might be the 14mm lenses. Here we have the Samyang 14mm f/2.8 ED AS IF UMC (£329), Samyang 14mm f/2.4 AE XP (£899), Canon EF 14mm f/2.8 L II USM (£2149) and the Nikon 14mm f/2.8 D AF ED (£1389).

For its unique position as the widest rectilinear lens and the high quality of the images it produces, the price tag seems very reasonable.

For more options have a look at the Top 15 Wide-angle Landscape Lenses.

Irix 15mm f/2.4 Verdict

The Irix 15mm f/2.4 lens is a powerful photographic tool. This new lens from Irix lifts the performance for such lenses way beyond the first early 1970s offerings and gives us a lens that is free from flare, and very sharp. This Swiss design is an excellent one, built in Korea to very high standards.

Irix 15mm f/2.4 Pros

Excellent sharpness, especially centrally
No flare evident
Virtually no CA
Weather resistance
Filter use possible
Electronic control of aperture
Nice bokeh
Thoughtful, ergonomic design and features

Irix 15mm f/2.4 Cons

Edges soft at wide apertures when close
Manual focus only

Features4.5/5

Handling4.5/5

Performance4.5/5

Value4.5/5

Overall Verdict

The Irix 15mm f/2.4 is a beautifully engineered lens that produces beautiful images.

Ease of Use

With a maximum diameter of 114mm and a length of 100mm, the Irix 15mm f/2.4 is an ultra-wide-angle fixed focal length optic that’s well-suited to full-frame DSLRs like the Canon EOS 5DS R that we reviewed it with. Weighing in at 608g for the Canon version, it’s quite heavy, making this lens better suited to life on a tripod than to being used hand-held. It is also compatible with APS-C cameras, where it will produce a 22.5mm equivalent focal length.

The Irix 15mm f/2.4 lens mounted on a Canon EOS 5DS R

The Irix 15mm f/2.4 lens alongside a Canon EOS 5DS R

Two versions of the Irix 15mm f/2.4 lens are available, differing in their build quality. The standard Firefly version that we reviewed is made of lightweight composite plastics, covered in an anti-slip rubber coating with printed markings. The more expensive Blackstone version has a aluminum/magnesium alloy body for extra durability, plus engraved fluorescent markings which reflect UV light, making it easier to use in the dark. Note that the Blackstone version is slightly heavier.

The side of the Irix 15mm f/2.4 lens

The Irix 15mm f/2.4 has 15 lens elements in 11 groups, including 3 high refractive lenses, 2 ED lenses and 2 aspherical lenses, and a 9-bladed rounded diaphragm helps to provide smooth bokeh blur.

With no need for a zoom ring, the manual focusing ring spans a significant width of the lens barrel and is exceptionally smooth to operate, complete with a useful hyperfocal scale and a handy infinity click-stop feature.

The front of the Irix 15mm f/2.4 lens

The rear of the Irix 15mm f/2.4 lens

The Irix 15mm f/2.4 lens has a a convenient focus lock mechanism, activated by a slim ring that sits between the end of the lens and the focusing ring, although we did find it stiff to operate.

The side of the Irix 15mm f/2.4 lens

There’s no optical image stabilisation, but the lens’ very short focal length and fast maximum aperture mostly alleviate the need for it. A removable metal petal-shaped lens hood is fitted, which means that you can use a front filter system with this lens. You can alternatively choose to fit rear gelatin filters.

The Irix 15mm f/2.4 lens in-hand

The Irix 15mm f/2.4 lens with the supplied hood fitted

Both versions of the Irix 15mm f/2.4 have the same level of weather-sealling against dust and moisture, with two seals around the focus ring and one on the bayonet mount.

The Firefly version of the Irix 15mm f/2.4 includes a soft lens pouch, while the Blackstone version ships with a hard lens case. Both versions include an extra rear lens cap.

The 15mm focal length gives an angle of view of 110 degrees on a 35mm full frame sensor.

Field of view at 15mm

Chromatic Aberrations

Chromatic aberration (purple fringing) isn’t that much of an issue with the Irix 15mm f/2.4 lens, only appearing as purple or green fringing in a few of our test shots, as shown in the example 100% crops below.

Light Fall-off and Distortion

Light fall-off is noticeable wide open at f/2.4, though this is to be expected for such a wide-angle lens and can easily be corrected in Photoshop. Stop down to f/5.6 and the vignetting is already less prominent, but it is still visible when shooting pale scenes that fill the frame. Barrel distortion is quoted by Irix as being a minimal 2%.

Light fall-off at 15mm

Macro

A 25cm / 0.82ft minimum focus distance makes the lens useful for shooting reasonably close subjects. This image is uncropped and shows how close you can get to a Compact Flash card.

Close-up performance

Sharpness

In order to show you how sharp this lens is, we are providing 100% crops on the following page.

Ease of Use
Sharpness: 15mm
Sample Images
Lens Specs
Rating & Conclusion
Main Rivals
Review Roundup

Irix 11mm f/4 Chromatic Aberration Charts

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Chromatic aberration (CA) is the lens’ inability to focus on the sensor or film all colours of visible light at the same point. Severe chromatic aberration gives a noticeable fringing or a halo effect around sharp edges within the picture. It can be cured in software.
Apochromatic lenses have special lens elements (aspheric, extra-low dispersion etc) to minimise the problem, hence they usually cost more.
For this review, the lens was tested on a Canon EOS 5DS R using Imatest.

Absence of flare is highly creditable. Even into the sun, there are no artefacts and the images display good contrast, diminished slightly but not significantly. Considering the very wide field of view, this makes the lens absolutely usable in all lighting conditions without fear of ghosting effects.

There is -3.70% barrel distortion, hardly surprising. That measures slightly higher than the Irix claim of -3.13%. However, we expect barrelling from ultra wides so our eyes will not find that too disconcerting. Again, the distortion can be tacked in software if desired.

Bokeh is almost not a consideration with an 11mm lens. Unless really sought after, out of focus backgrounds are not the norm and they can look a little odd. The ultra-wide edges when way out of focus look smeared and this is probably not the way to use this lens.

Despite the huge challenges in making a lens of this type, Irix has overall done a splendid job of it, the quality is definitely there and it shows.

Full-Frame Non-Distorting 110º Ultrawide

Irix 15mm f/2.4 in metal «Blackstone» barrel, Canon version (95mm or rear gel filters, 22.6 oz./642g, 0.8’/0.25m close-focus, about $675; $425 for same optics in «Firefly» plastic outer barrel). bigger. It comes in mounts for Nikon, for Canon and for Pentax. I’d get it at Adorama, at Amazon or at B&H.

This all-content, junk-free website’s biggest source of support is when you use those or any of when you get anything, regardless of the country in which you live. Irix does not seal its boxes in any way, so never buy at retail or any other source not on since you’ll have no way of knowing if you’re missing accessories, getting a defective, damaged, returned, store demo or used lens. Buy only from the for the best prices, service, return policies and selection. Thanks for helping me help you! Ken.

April 2018 Irix Nikon Canon Sony Fuji LEICA Zeiss Laowa Samyang All Reviews

Aberrations and Distortion

Realistically, this is one of the best lenses I’ve ever worked with as far as handling such a wide angle without having to deal with much dramatic distortion or aberration. For such a wide lens, I was legitimately impressed with how each image came out. Sure, there is a little bit of in-camera distortion and vignetting, but not nearly as much as what I expected to see. Irix has also made their own lens profiles available for download for post-processing lens corrections. But even without the profile corrections, I was still very happy with how each image turned out. Below is an example of the shot before lens profile corrections and after the corrections have been applied.

As far as aberration goes, this is probably one of the best lenses with which I have ever worked. Below is the best example I could find out of all the shots I took with it that showed any chromatic aberration and, even then, it barely shows any at all. I’ve taken a range of images of different subjects at different times of day, and still this is one of the only images that showed even a little bit of chromatic aberration. I am legitimately impressed with how the Irix holds up here.

Some chromatic aberration shows in more contrasting areas, but really only slightly.

Irix 11mm f/4 MTF Charts

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CA (Chromatic Aberration) is not easy to correct in such a wide lens, but Irix has done a good job. Centrally, CA is well held to under half a pixel. At the edge CA is visible, but this can be tackled in software. A good result.

Specifications

Names

Irix calls this the Irix 15mm f/2.4 Blackstone, or the plastic barreled version as the Irix 15mm f/2.4 Firefly.

I’m reviewing the Blackstone version for Canon. The other versions have the same optics.

Optics

Irix 15mm f/2.4 Internal Optical Construction. bigger.

15 elements in 11 groups.

2 aspherical elements.

2 extra low dispersion elements.

3 high refractive-index elements.

Multicoated; branded as «neutrino.»

Rear focussing.

Diaphragm

Irix 15mm f/2.4 at f/2.4; diaphragm not visible. bigger.

9 rounded blades.

Stops down to f/22.

Focal Length

15 mm.

When used on APS-C cameras, it sees the same angle of view as a 24 mm lens sees when used on a 35mm or full-frame camera.

Hood

Irix 15mm f/2.4, Blackstone version for Canon. bigger.

Plastic bayonet ILH-15A hood, included.

Sliding access hole to rotate filters with hood attached.

Irix 15mm f/2.4 Blackstone included case. bigger.

Sculpted semi-hard case included.

Size

3.94″ maximum diameter × 3.31″ extension from flange.

100 mm maximum diameter × 84 mm extension from flange.

Weight

22.625 oz. (641.5 g) actual measured weight, lens only, Canon Blackstone.

23.765 oz. (673.75 g) with included hood as shown.

Irix specifies:

Firefly

Blackstone

Canon

608 g.

21.4 oz.

685 g.

24.2 oz.

Nikon

581 g.

20.5 oz.

653 g.

23.0 oz.

Included

Irix 15mm f/2.4 Blackstone packaging. bigger.

Fancy metal box holding paperwork.

Lens.

Front and rear caps.

Spare rear cap.

Hood.

Case.

Irix 15mm f/2.4, Blackstone version for Canon with included caps and hood. bigger.

Price, USA

April 2018: $675 in metal «Blackstone» barrel; $425 with plastic «Firefly» outer barrel.

May 2017: $599 in metal «Blackstone» barrel; $399 with plastic «Firefly» outer barrel.

Irix 15mm f/2.4 Blackstone. bigger.

Irix 11mm f/4 Firefly Handling and Features

A huge plastic snap-on lens hood protects the equally huge, bulbous front element. When in use, this vulnerable front element is protected from impact and from flare by the efficient looking petal lens hood. The hood is fixed and a part of the lens barrel so there is no possibility of using filters. In any event, keeping feet and the photographer’s shadow out of the images is something to watch and a filter mount would almost certainly intrude on the field of view.

This is a manual focus lens and just behind the hood is a locking ring that can be used to fix the focus at a desired position. Immediately behind this is the focusing ring, wide enough to give a good grip and very smooth in operation. On the Firefly version, this also has a raised area to assist grip even further. The distance scale is marked in feet and metres, from infinity down to 0.275m, or 0.9 feet. This is close, but the lens is so wide that initially, it is quite surprising how much is actually included in the frame.

An unusual feature of the distance scale is the inclusion of a Hyperfocal Distance scale. Just lining up the aperture in use with the focus index mark sets the lens to the hyperfocal distance for that aperture. This is a simple and ingenious thought that will be very helpful when seeking to maximise depth of field. It is also useful to set a “snapshot” setting as focusing the lens by eye is well nigh impossible. Modern AF screens do not have the acuity to see the point of focus, and many eyes won’t either. The only real way to focus is to set the scale to the estimated or measured distance. Fortunately, the enormous amount of depth of field allows this to be a practical way to achieve good focus.

There is also a very clear depth of field scale, and an innovative light click stop at the infinity point of the focusing ring, so this can be set even in poor light by feel. The Firefly version of the lens has painted markings, but the more expensive Blackstone has engravings filled with luminous paint, a feature that is really useful in low light.

Finally, the position of the focusing scale can be adjusted as well. Just behind the front of the lens, there is a small access point and by screw adjustment, the position of the focusing scale can be fine tuned for maximum accuracy.

Even the original 15mm f/3.5 lenses of the early 1970s used aspheric elements, so it is no surprise that this 11mm f/4 lens has an optical construction of 16 elements in 10 groups and includes 4 HR (High Refractive Index), 2 ED (Extra Low Dispersion) and 3 Aspherical elements. Neutrino coating helps make this possible, the Irix version of nano coating. 9 rounded diaphragm blades result in a more circular aperture, for improved bokeh.

This is a chunky, heavy lens, the Firefly version weighing in at 783g. There is sealing against dust and moisture, another welcome feature in any lens.

The biggest handling issue, if it is an issue, is likely to be focusing. As mentioned, using the viewfinder or Live View is not really possible, so measuring or estimating distances is a way forward. For most outdoor shooting selecting the hyperfocal distance for the aperture in use works very well. After that, just shoot away, with no need to worry about any further focusing.

Other than that, if you like wide angle lenses then this one is so wide that it opens all sorts of creative possibilities. The wide breadth of sweeping landscapes is incredible, but do watch that there is a strong foreground interest to avoid wide swathes of empty space. It is also necessary to get in close, closer, closer….and still the subject can be too small. The sample images of buildings were shot at incredibly close distances to fill the frame, and, of course, this presents all sorts of challenges regarding perspective and the “drawing” of the straight lines. Things look normal but very wide when the camera back is parallel to the subject, but tilt it even slightly and we enter a new world.

Firefly & Blackstone Comparison Table

Firefly and Blackstone versions use the same optics and the same precision, but this table, from the Irix website, summarises the differences.

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Irix 11mm f/4 Firefly Verdict

Irix 11mm f/4 Firefly Pros

Irix 11mm f/4 Firefly Cons

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Image Quality

Sharpness

Vignetting

Contrast

Low Light Handling

Bokeh

Focusing

Introduction

Blackstone (metal) or Firefly (plastic) outsides?

Sample Images

Irix 15mm f/2.4 Performance

How to read our charts

How to read our charts

Usage

f/2.4?

Lens Hood

Focus

Irix 11mm f/4 Sample Photos

Value For Money

Irix 15mm f/2.4 Verdict

Irix 15mm f/2.4 Pros

Irix 15mm f/2.4 Cons

Ease of Use

Chromatic Aberrations

Light Fall-off and Distortion

Macro

Sharpness

Irix 11mm f/4 Chromatic Aberration Charts

Full-Frame Non-Distorting 110º Ultrawide

Aberrations and Distortion

Irix 11mm f/4 MTF Charts

Specifications

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Optics

Diaphragm

Hood

Size

Included

Price, USA

Irix 11mm f/4 Firefly Handling and Features

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