The best lenses for astrophotography are arguably the most important tools in your arsenal for getting clear, sharp images of the night sky. An astro lens needs to offer a wide-angle perspective, not just for capturing as much of the sky as possible, but also for allowing the use of slower shutter speeds without incurring star trails (i.e. stars smearing across the sky). A fast maximum aperture is also critical.
There's more to it of course – and we get into the weeds in our 'how to choose' section at the bottom of this page – but that's the essence of the matter. Astrophotography is an immensely enjoyable shooting discipline, but getting great results is technically challenging. We go into a lot more detail in our astrophotography tipsand how-to guide, but choosing the right lens is one of the most important first steps to take.
So then, here are the best astrophotography lenses we've ever tested! We've endeavoured to make sure that there are options for all the major systems you're likely to be using, including both DSLRs and mirrorless cameras, so as you can imagine, this is a long list! However, there are a fair few lenses on this list that are available for multiple systems. The one thing they all have in common is that they'll do a fantastic job of producing clean, sharp images of the night sky! You'll also need one of the best tripods and the best cameras for astrophotography, so make sure to check those guides out too if you haven't already.
Our go-to lens expert
Our go-to lens expert
Matthew Richards
Matthew Richards is a photographer and journalist who has spent years using and reviewing all manner of photo gear. He is Digital Camera World's principal lens reviewer – and has tested more primes and zooms than most people have had hot dinners! Here, he's picking the lenses that have most impressed him for astrophotography.
From Korean manufacturer Samyang’s XP stable of premium manual-focus prime lenses for Canon and Nikon full-frame cameras, this 14mm f/2.4 is the most ideal for astrophotography. The lens is sold as the Rokinon SP 14mm f/2.4 in North America.
Available in Canon EF and Nikon F mounts, this Sigma lens is up against own-brand legends and beats them for image quality and price. Build quality and handling are excellent, with a full set of weather-seals and a fluorine coating on the front element.
It's big and it's heavy, but this spectacular full-frame prime delivers image quality that's beyond reproach – and it's available for both mirrorless and DSLRs.
While it's a "dumb" lens with no electronic communication to speak of, this Samyang lens is wide enough to suit APS-C cameras – and is available in a variety of mount options.
This professional lens is outstanding if you're using full-frame Canon DSLRs. Sharpness is exceptional right to the corners of the frame – though Sigma's 14-24mm has it beat.
This legendary lens for Nikon DSLRs may be a decade old, but it still holds its own in a competitive market. Sharpness does suffer at the 14mm end, however.
It's another expensive lens, but Nikon went all out with the quality of this one to woo photographers to its Z-mount. As such, the image quality is absolutely stellar.
You can't argue with a G Master, and Sony's professional wide-angle zoom is a dazzler of a lens. Quality is excellent, handling is sublime – it's tough to find fault.
Available exclusively for Sony E-mount, this full-frame prime is an excellent choice for astro shooters on a tight budget. It can be purchased with or without autofocus.
This wide lens is a solid choice for astro work. The optical path of this small lens is particularly impressive, with 13 elements somehow crammed in there.
If you prefer to use a Panasonic-branded lens with your Panasonic MFT camera, the Leica DG Summilux 9mm f/1.7 lens is a brilliant option for astrophotography.
Pleasingly compact, this lens for Fujifilm X delivers excellent optical performance even when used wide open. Like many Fuji lenses, it also benefits from a physical aperture ring.
If you're shooting astro images on a Pentax DSLR, this Irix lens could prove to be an inexpensive asset. Just be careful at f/2.4 – we encountered some coma distortion.
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Max angle of view (diagonal): 114 degrees (Full-frame)
Dimensions (WxL): 87x106mm
Weight: 791g
Reasons to buy
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Generous viewing angle
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Superb image quality
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Good build and handling
Reasons to avoid
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Only for Canon and Nikon DSLRs
From Korean manufacturer Samyang’s XP stable of premium manual-focus prime lenses for Canon and Nikon full-frame cameras, this 14mm f/2.4 is the most ideal for astrophotography. The lens is sold as the Rokinon SP 14mm f/2.4 in North America.
The high-quality glass is neatly wrapped in a really solid casing. The rubberized manual focus ring gives a very assured grip and has a long rotational travel with a fluid feel. There’s no weather-seal ring on the mounting plate to guard against the ingress of dust and moisture. To be fair, though, if you’re photographing the Milky Way, you’ll need clear, dry and dust-free conditions.
In our review, we were hugely impressed by how well this lens maintained its image quality when wide open, which is hugely important for astrophotography. It's markedly better than Irix's rival 15mm f/2.4 Blackstone lens or a Sigma 14mm f/1.8 DG HSM Art. Sharpness is both very good and extremely consistent across the image frame. Chromatic aberrations are negligible, while coma and astigmatism are very minimal. Barrel distortion can be visible at close focus distances, but that's not an issue for astrophotography.
Maintaining excellent image quality a lens' widest aperture for astrophotography is a real challenge in an ultra-wide-angle optic, but this Samyang does exactly that – an admirable achievement.
Max angle of view (diagonal): 114 degrees (Full-frame)
Dimensions (WxL): 95x126mm
Weight: 1,150g
Reasons to buy
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Focal length flexibility
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Superb all-round image quality
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Superb, weather-sealed build
Reasons to avoid
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Price higher than most
Available in Canon EF and Nikon F mounts, this Sigma lens is up against own-brand legends like the Canon EF 16-35mm f/2.8L USM III and the Nikkor AF-S 14-24mm f/2.8G ED. It beats both of them for image quality and price. Build quality and handling are excellent, with a full set of weather-seals and a fluorine coating on the front element. The lens is also compatible with Sigma’s optional USB Dock for customisation and firmware updates.
In our review, we found we could produce images with this lens that were nothing short of outstanding. Even at the shortest focal length with the widest aperture, sharpness is excellent across the entire frame, and the lens does very well to retain excellent corner sharpness at wide apertures.
Vignetting is remarkably minimal and though barrel distortion is prominent at close range, it's negligible for astrophotography. Lateral and spherical aberrations are also very well controlled.
For full-frame Canon and Nikon DSLRs, this is simply the best ultra-wide, fast-aperture zoom lens on the market, and not just for astrophotography.
Mount: Canon EF, Nikon F, Sony FE, L-mount, Sigma SA
Full-frame compatible: Yes
Autofocus: Ring-type ultrasonic AF
Stabiliser: No
Diaphragm blades: 9
Max angle of view (diagonal): 114 degrees (Full-frame)
Dimensions (WxL): 95x109mm
Weight: 1,170g
Reasons to buy
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Fast AF
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Fab sharpness, contrast and colour
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Luxury build
Reasons to avoid
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Big and heavy
This full-frame prime lens is available for Canon and Nikon DSLRs, and has more recently been adapted for Sony E-mount, as well as the L-mount alliance between Leica, Panasonic and Sigma. It's a full f/stop faster than most other lenses on this list, and it includes super-speedy ring-type ultrasonic autofocus. The wide aperture comes at a price, however: the large-diameter elements required are not only more expensive to make, they also result in a comparatively big and heavy build.
At least this lens is also big on performance. When we reviewed the lens we found the image quality to be fabulous, with exceptional sharpness for such a fast-aperture lens with an ultra-wide viewing angle.
Equally impressive are contrast, color rendition, and the absence of spherical and lateral chromatic aberrations. There is very noticeable coma and astigmatism towards the corners of the image frame, but go down one stop and these virtually disappear, making overall image quality for astrophotography altogether excellent.
A newer, faster version of the lens, the Sigma 14mm F1.4 DG DN Art, is now available for Sony and L-mount full-frame mirrorless cameras.
Mount: Canon EF-S, Canon EF-M, Nikon DX, Sony E, Sony A, Fujifilm X, MFT, Pentax K, Samsung NX
Full-frame compatible: No
Autofocus: No
Stabiliser: No
Diaphragm blades: 6
Max angle of view (diagonal): 106 degrees (APS-C)
Dimensions (WxL): 76x98mm
Weight: 590g
Reasons to buy
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Precise manual focusing
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Solid build quality
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Great value
Reasons to avoid
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Average sharpness
This manual-focus Samyang has an astro-friendly ‘effective’ focal length on crop-sensor cameras, ranging from 15-16mm on APS-C format bodies to 20mm on Micro Four Thirds. It’s available in many mount options, but only the Nikon fit has built-in electronics. This enables the aperture to be set from the camera. Compared with most prime lenses for crop-sensor cameras, this one is unusual in combining a wide viewing angle with a fairly fast f/2.8 aperture.
Manual focusing is precise and assured. The build quality feels solid, but there are no weather seals. Performance is good in terms of coma, spherical aberration and vignetting, helping stars to retain their natural shape across the image frame, even when shooting wide-open at f/2.8. Sharpness isn’t fabulous, however, but it doesn’t drop off much towards the edges of frame. Color fringing can be more noticeable than usual towards the image corners, and there's a fairly typical amount of barrel distortion for this type of wide-angle prime.
This lens works well for Micro Four Thirds and APS-C format astrophotography, where the lack of autofocus isn’t really a drawback. It’s great value at the price. See our full Samyang 10mm f/2.8 ED AS NCS CS review.
Max angle of view (diagonal): 108 degrees (Full-frame)
Dimensions (WxL): 89x128mm
Weight: 790g
Reasons to buy
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Top build quality
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Fast, accurate AF
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Weather-resistant
Reasons to avoid
-
Corner sharpness nothing special
If you own a full-frame Canon DSLR, this is Canon’s most ideal zoom lens for astrophotography. It may not be as wide-angle as the company's EF 11-24mm f/4L USM, but it's an all-important f-stop faster. The maximum viewing angle is admittedly slightly less than the 14mm and 15mm full-frame on this list, equating to 108 degrees compared with 114 or 110 degrees.
This lens gains a large and complex double-surface GMO (Glass Moulded) aspherical element at the front, adding to two UD (Ultra-low Dispersion) elements and a ground aspherical element at the rear. Upgraded, high-tech coatings include both SWC (SubWavelength Coating) and ASC (Air Sphere Coating) for greater resistance to ghosting and flare. Weather-resistant attributes are extended to include moisture- and grease-repellent fluorine coatings on the front and rear elements. The lens is quite long at 128mm, considering that it doesn’t have a built-in fixed hood. Unlike with some rival lenses, the separate bayonet-fit hood enables the easy attachment of filters, via an 82mm thread. Build quality is up to Canon’s usual robust L-series standards.
We tested the Canon EF 16-35mm f/2.8L USM III in our lab, and found sharpness and contrast to be exceptionally impressive across the zoom range. The Mk III has much-improved corner sharpness compared with the previous edition, but still lags behind the competing Sigma 14-24mm zoom. There’s very little spherical aberration at f/2.8, but coma and astigmatism can be quite visible near the extreme corners of the frame.
Max angle of view (diagonal): 110 degrees (Full-frame)
Dimensions (WxL): 88.5x127mm
Weight: 840g
Reasons to buy
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5-stop Image Stabilizer
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Smaller than EF equivalent
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No apparent distortion
Reasons to avoid
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Edge definition average
If you've got an EOS R5 or R6 and want to do astrophotography, this is the dedicated lens for you. It's no surprise when you look at the focal range and maximum aperture available to find out that this is a big and heavy lens. It just about balances okay on one of Canon's mirrorless cameras, but should be less of an issue for astrophotographers. A nice touch is the separate hood that means it's possible to attach filters if desired via an 82mm filter thread, while there's also built-in IS.
We found the focusing performance of the Canon RF 15-35mm f/2.8L IS USM to be brilliant in testing, with the lens enjoying a Nano Ultrasonic AF system for virtually silent focusing. Oh, and did we mention that stellar image quality? A brilliant lens, but it does come with a hefty price tag.
Max angle of view (diagonal): 108 degrees (full-frame)
Dimensions (WxL): 40.1x69.2 mm
Weight: 165g
Reasons to buy
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Fast, wide and lightweight
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Affordable price tag
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Clear, crisp image quality
Reasons to avoid
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Not weather-sealed
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Reliant on corrections
Many astrophotographers prefer primes to zoom for their optical quality, as well as the fact that they'll likely only be using the wide end of a zoom anyway. For Canon RF users, the RF 16mm F2.8 STM is an ideal choice of lens, especially given its relatively affordable price tag compared to the big professional primes and zooms. With a wide angle of view, it's ideal for filling the frame with expansive starry vistas, and also provides more latitude for longer shutter speeds without star trails.
Sharpness and clarity are generally very good, as we discovered in our review – the lens is quite reliant on in-camera corrections, but that's quite common these days, and they work well. The manual focusing operation is nice and smooth, with a pleasing level of precision, and while there isn't fully-fledged weather sealing, the lens feels reasonably robust and well constructed.
Max angle of view (diagonal): 114 degrees (Full-frame)
Dimensions (WxL): 98x132mm
Weight: 1,000g
Reasons to buy
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Wide viewing angle and fast aperture
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Useful zoom range
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Great build
Reasons to avoid
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Vignetting and distortion at 14mm
With its ultra-wide zoom range and fast, constant-aperture design, this Nikon FX-format lens was a world-first when it was launched back in 2008. It’s become something of a legend in its own lifetime, but struggles to retain its crown against new Sigma 14-24mm and Tamron 15-30mm pretenders to the throne. The Nikon matches the Sigma zoom lens for maximum viewing angle and is slightly wider than the Tamron.
Optical highlights include two ED (Extra-low Dispersion) elements and Nano Crystal Coat. A rubber weather-seal is featured on the mounting plate but the lens lacks a comprehensive set of weather-seals or a keep-clean fluorine coating on the front element, as featured on the Sigma and Tamron lenses.
Centre-sharpness is excellent but corner-sharpness at the shortest focal length and widest aperture lags behind that of the Sigma zoom, more on a par with the Tamron. Vignetting and barrel distortion are rather worse than in both other lenses. Coma and astigmatism are controlled very well, again similar to the Tamron lens but not quite equaling the performance of the Sigma.
The Nikkor Z 14-24mm f/2.8 S is Nikon's latest effort to attract pros to the Z mount system. Completing the holy trinity of fast f/2.8 S-line zooms, it slots in neatly next to the Nikkor Z 24-70mm f/2.8 S and promises uncompromising wide-angle image quality. The 16-element optical stack includes 3 aspherical elements, along with Nikon’s Nano Crystal and ARNEO Coat for reducing ghosting and flare.
As you might expect, Nikon went all guns blazing with the design of this lens to try and sway photographers to the Z mount. As such, the build, handling and image quality of this lens are all absolutely top-tier. Copiously weather-sealed, with scintillating sharpness, this is a lens for those who demand the best (and it comes with the kind of price tag you might expect).
The front element gets a smear-resistant fluorine coating, and the lens is fully weather sealed. Add the included HB-98 lens hood and huge 112mm filters can be used - Nikon offers Neutral Color and Circular Polarizer options.
Max angle of view (diagonal): 122-84 degrees (Full-frame)
Dimensions (WxL): 98x137mm
Weight: 847g
Reasons to buy
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Impressive image quality
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Impeccable handling
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Ultra-wide maximum viewing angle
Reasons to avoid
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Expensive option
Only until recently, the FE 12-24mm f/4 G has been Sony’s most wide-angle zoom. However, with a constant maximum aperture of f/4, it isn't suited to astrophotography. Step forward the Sony FE 12-24mm f/2.8 G Master. We tested out this lens both in our lab and out in the field, and completely fell in love. Its impeccable image quality and ultra-wide viewing angle makes it an outstanding choice for astrophotography.
Boasting a diagonal coverage up to an incredible 122 degrees, while also delivering a fast and constant f/2.8 aperture, this combination makes it the world’s fastest lens in its class. There's no getting away from the hefty price, but this is a lens that delivers supreme image quality, while the AF system is quick, smooth and quiet. Factor in the lovely handling and rock-solid build quality and this is a stunning lens.
Max angle of view (diagonal): 92 degrees (Full-frame)
Dimensions (WxL): 89x92mm
Weight: 464g
Reasons to buy
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Fast AF useful for general shooting
+
Great centre sharpness
+
Minimal distortion
Reasons to avoid
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Focal length relatively restrictive
Designed for full-frame Sony E-mount cameras, the Firin 20mm is available in two versions, either with or without autofocus. This 'AF' autofocus version looks clean, simple and in-keeping with Sony mirrorless cameras. Autofocus is reasonably quick and generally very accurate. It’s definitely worth having for general shooting. When focusing manually, the large focus ring operates with smooth precision. Compared with the other lenses on this list, the Firin has a reduced viewing angle of 92 degrees, but its f/2 aperture rating is faster than average.
Shooting wide-open, coma and astigmatism are apparent towards the corners of frame, but narrowing the aperture by an f/stop cures the problem. However there's no cure for the disappointing corner sharpness, which is especially poor until you stop down to f/4. There’s remarkably little colour fringing, even at the extreme corners of the frame, and distortion is practically non-existent.
Overall the Firin is a fine lens, although its viewing angle can feel a little restrictive for astrophotography. See our full Tokina Firin 20mm f2 AF review.
This is the widest lens in Sigma's growing range of I-series primes for Sony E-mount and Leica L-mount, and it's a solid choice for astro work. The optical path of the lens is particularly impressive, especially considering how small the lens is – 13 elements are somehow crammed in there, including three high-precision glass-molded aspherical elements, one SLD (Special Low Dispersion) element and one FLD (Fluorite Low Dispersion) element. Then there's also Sigma's Super Multi-Layer Coating and Nano Porous Coating.
Therefore, as you might expect, the Sigma 20mm F2 DG DN | C performed very well in our testing, delivering excellent sharpness. We found that vignetting was a little severe when used at wider apertures than f/5.6, and there is some distortion that will require cleanup in software, but nothing ruinous.
The 'C' or 'Contemporary' designator means it's a lightweight and portable lens – though this doesn't matter as much for astrophotography as it does for other disciplines, as you're always going to be tethered to your tripod. Still, the metal construction is pleasingly solid, and the addition of an aperture ring is welcome.
The 2x crop factor of Micro Four Thirds cameras can make it tricky to find a high-quality lens that's wide enough for astrophotography – however, we really rate this Olympus lens, the M.ZUIKO DIGITAL ED 7-14mm 1:2.8 PRO. Mounted on an MFT body, it provides an equivalent focal range of 14-28mm, and thanks to its bright f/2.8 aperture that runs through the zoom range, is an excellent choice for astro work.
In our review, the lens achieved impressive results throughout our lab tests, delivering excellent sharpness even when used wide open. It's well built too, with enough weather-sealing to handle the long nights it'll spend outside while you're busy shooting the stars. It's on the expensive side for an MFT lens, and arguably on the heavy side too, but since you won't be shooting handheld, the latter shouldn't be too much of an issue.
For users of Panasonic MFT cameras, this is an excellent astro lens.
Specifications
Mount: Micro Four Thirds
Full-frame compatible: No
Autofocus: Yes
Stabiliser: No
Diaphragm blades: 7
Max angle of view (diagonal): 100 degrees
Dimensions (WxL): 60.8x52 mm
Weight: 130g
Reasons to buy
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Useful f/1.7 aperture
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Good central sharpness
+
Dust/splashproof design
Reasons to avoid
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Dropoff in corners
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No physical buttons
While Micro Four Thirds lenses and cameras are completely cross-compatible, many users prefer to stick with one manufacturer as much as possible, as the functionality of features like autofocus tends to work a little better. If you're using Panasonic MFT cameras and want a corresponding astro lens, the Panasonic Leica DG Summilux 9mm f/1.7 ASPH is a good choice.
A relatively recent release (from 2022), this ultra-light prime delivers an equivalent focal length of 18mm, which is nice and wide for astrophotography. Its maximum aperture of f/1.7 gives you a good amount of latitude for low-light, and the lightweight build has a degree of weatherproofing for long, cold dewy nights spent chasing stars. The lens does rely a fair amount on in-camera optical corrections (as is common these days) but central sharpness is reliably very good.
In 2019, Fujifilm debuted its widest lens yet, the Fujifilm 8-16mm f2.8 XF R LM WR Fujinon Lens. Its size and price tag put it firmly in the same camp as the pro optics; weighing more than 800g, when it's paired with one of the larger cameras like the X-T3, this lens makes for a setup that calls the mirrorless reputation for lightness into question. Don't get us wrong though, this is a fantastic lens, as we noted in our full review.
A sophisticated optical construction ensures pin-sharp image quality, while it also has an extra f-stop over its nearest comparison point in the X stable, the 10-24mm (see below). It's worth being aware that the lens lacks optical image stabilisation of any kind, and its wide front makes it incompatible with screw-in filters. Nevertheless, this is as wide as ultra-wide zooms get, with a full frame equivalent focal length of just 12mm at its widest setting!
This is a pretty compact and lightweight lens for a wide-angle f/1.4, and boasts a really neat design and an everyday 62mm filter mount. The optical performance is stellar, even wide open, though there is already a 16mm f/1.4 in the Fujinon lens range, so it feels as if this lens is squeezing into a gap that isn't quite there.
There's no image stabilization, which we wouldn't expect in a fast prime anyway, but when we tested the lens we did find that there is an annoying 'clonking' sound from what we think is the AF actuator when the lens is removed from the camera and its AF system is not being powered.
Max angle of view (diagonal): 110 degrees (Full-frame)
Dimensions (WxL): 100x114mm
Weight: 685g
Reasons to buy
+
Solid build with florescent markings
+
Well-priced
+
Excellent centre-frame sharpness
Reasons to avoid
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Lacklustre corner sharpness
Designed in Switzerland and built in Korea, the full-frame compatible Irix 15mm is available in Firefly and Blackstone options. They’re optically identical, but the Blackstone has a magnesium alloy rather than plastic casing, four weather-seals instead of three, and fluorescent engraved markings for easy reading.
The lens is satisfying to operate, as we noted in our review. As a manual-focus lens, the focus ring has a smooth, precise operation and feels absolutely impeccable. A secondary ring enables you to lock the focus ring at any position. Another nice touch is that you can fine-tune the focus ring so that the distance scale is calibrated to your camera body.
Image quality is excellent, with minimal aberrations. Sharpness is excellent across most of the frame, even at the widest aperture. Vignetting isn’t too bad at f/2.4, but coma and astigmatism are pronounced, giving an irregular shape to stars. Both factors are improved by narrowing the aperture by an f/stop though.
This is a great wide-angle prime for general shooting, and comes at a very attractive price. Coma and astigmatism at the widest aperture are the only spoilers for astrophotography.
If you're picking an astrophotography lens, a wide-angle is almost certainly going to be the way to go. A lens with a nice, wide field of view is useful not only for getting as much of the night sky in the frame as possible, but also for minimising the "trailing" effect of stars. Astrophotography requires long shutter speeds, and assuming that you haven't mounted your camera and lens to a dedicated equatorial mount, too long a shutter speed will cause the stars to trail and blur across the sky as the Earth rotates. The shorter your focal length, the more leeway you have before this starts to happen.
This means that something else that can help is having a nice, wide maximum aperture, allowing the lens to drink in as much light as possible. You'll be able to use shorter shutter speeds at f/1.4 than you would at f/2.8 – however, you also need to balance this with the fact that you'll get better sharpness when you stop down.
For astrophotography lenses, it's especially important to look to minimise different types of distortion and aberration, all the way to the edges of the frame. Too much coma and astigmatism will give an irregular shape to stars, so it's a higher priority than usual to choose lenses that are as free as possible from these types of distortion. These are some of the many factors we assess when we test lenses, which you can read more about below.
We test lenses using both real world sample images and lab tests. Our lab tests are carried out scientifically in controlled conditions using the Imatest testing suite, which consists of custom charts and analysis software that measures resolution in line widths/picture height, a measurement widely used in lens and camera testing. We find the combination of lab and real-word testing works best, as each reveals different qualities and characteristics.
What focal length (mm) is best for astrophotography?
There are various focal lengths of lens that can be great for astrophotography, and which one is right for you will likely come down to personal preference. However, as a general rule you are looking for a wide-angle in order to fit in as much of the sky as possible and minimize star-trailing. Generally, you'll be looking at focal lengths between about 10mm and no more than 35mm on full-frame. Remember if you're using a smaller sensor size, you'll need to calculate the effective focal length using the crop factor (1.5x or 1.6x for APS-C; 2x for Micro Four Thirds), meaning you'll likely need the widest lens you can get your hands on.
Is f/2.8 enough for astrophotography?
While you naturally want as much light as possible when shooting at night, you don't necessarily always want to be shooting at a lens' maximum aperture for the simple reason that sharpness tends to suffer when a lens is wide-open – and sharpness is critical in astro. An f/2.8 lens will therefore be more than acceptable in getting great astro shots – as you'll be able to see from the fact that we've included plenty of them in this guide. Faster lenses, however, mean that you that you don't have to increase ISO so much - and therefore will tend to allow you to produce images with less noise.
What is the 500 rule in astrophotography?
The 500 rule is a simple means of roughly calculating how long an exposure you can get away with taking of the night sky before star trails start to appear. Because this is largely affected by the focal length of your lens, the formula works by taking the number 500 and dividing it by your lens' focal length (in mm). The answer is the number of seconds you can expect to open the shutter for before star trails appear
So, if we were using the Samyang XP 14mm f/2.4 from the top spot on our list, we would divide 500 by 14 to reach a result of 35.71 – about 35 seconds before we get perceptible star trails.
Matthew Richards is a photographer and journalist who has spent years using and reviewing all manner of photo gear. He is Digital Camera World's principal lens reviewer – and has tested more primes and zooms than most people have had hot dinners!
His expertise with equipment doesn’t end there, though. He is also an encyclopedia when it comes to all manner of cameras, camera holsters and bags, flashguns, tripods and heads, printers, papers and inks, and just about anything imaging-related.
In an earlier life he was a broadcast engineer at the BBC, as well as a former editor of PC Guide.