Best Lens for Sony a6400: 4 Upgrades After the Kit Zoom

For most a6400 owners, the best lens after the 16-50mm kit zoom is a stabilized one: the Tamron 17-70mm F2.8 if you want a zoom, or the Sony E 35mm F1.8 OSS if you want a small prime.

Digital Camera World describes the 16-50mm power zoom that usually ships with the a6400 as very compact and convenient but a bit lacking in optical quality. Each lens below is a step up from it in a different direction. Before you buy, check the maker's compatibility list for the a6400 so you know the lens and its features are supported on your body.

Why stabilization matters on the a6400

When the camera body does not stabilize the sensor, the lens is what steadies your handheld shots. Optical stabilization goes by different names: Sony calls it Optical SteadyShot (OSS), and Tamron calls it VC, for Vibration Compensation.

Tamron says its VC system reduces blur from camera shake during handheld shooting at slow shutter speeds, for example indoors, at twilight or for nightscapes. For video, Tamron says the stabilization automatically adjusts to a wide range of shooting situations. Sony's lens literature for the E 35mm F1.8 OSS says the built-in Optical SteadyShot keeps both photos and videos crisp and blur-free.

Stabilization does not freeze a moving subject. It only cancels your own hand movement. A user review posted on Imaging Resource makes the same point about the Sony 35mm: the stabilization works well in darker conditions, but you should not depend on it too much.

How APS-C framing changes focal lengths

The a6400 uses an APS-C sensor, so every lens frames tighter than the same focal length would on a full-frame camera. The crop factor for Sony APS-C works out to 1.5x. Sigma lists its 30mm lens as a 45mm equivalent on an APS-C Sony body, and Digital Camera World gives the Sony E 18-135mm f/3.5-5.6 OSS an equivalent range of 27-202mm.

This matters when you choose a focal length. A 35mm prime, which is a classic wide-ish lens on full frame, behaves like a normal lens on the a6400. Sigma describes a prime of around 50mm equivalent as offering an angle of view very similar to human vision.

Lens	Focal length	Full-frame equivalent (x1.5)
Sony 16-50mm kit zoom	16-50mm	24-75mm
Tamron 17-70mm F2.8 Di III-A VC RXD	17-70mm	25.5-105mm
Sigma 18-50mm F2.8 DC DN Contemporary	18-50mm	27-75mm
Sigma 30mm F1.4 DC DN Contemporary	30mm	45mm
Sony E 35mm F1.8 OSS	35mm	52.5mm

The equivalents above apply the 1.5x factor that Sigma and Digital Camera World use.

The four lenses at a glance

Lens	Maximum aperture	Stabilization	Notable spec
Sony E 35mm F1.8 OSS	f/1.8	Yes, Optical SteadyShot	Compact second lens
Tamron 17-70mm F2.8 Di III-A VC RXD	f/2.8 constant	Yes, VC	525g, 4.1x zoom
Sigma 18-50mm F2.8 DC DN Contemporary	f/2.8 constant	Not listed in the evidence	Weather-resistant, 3x zoom
Sigma 30mm F1.4 DC DN Contemporary	f/1.4	No stabilizer	45mm equivalent

Sony E 35mm F1.8 OSS: the stabilized small prime

Sony's lens literature pitches the E 35mm F1.8 OSS as an ideal second lens that is easy to carry. Sony lists snapshots, night shots and portraits with defocused backgrounds among its uses, and credits the bright maximum aperture for the night shots. Sony also says newly designed optics reduce spherical aberration and coma for sharp images wide open.

The maximum aperture of f/1.8 lets in far more light than the kit zoom, and the built-in Optical SteadyShot steadies both stills and video. That combination makes it the most forgiving prime here for handheld shooting in dim rooms.

A user review posted on Imaging Resource says the lens delivers image quality well above the kit power zoom and calls it a good buy for its OSS and f/1.8 aperture. The same reviewer found the focus ring stiff to turn, which matters if you plan to focus manually for video.

Pick this lens if you want one small prime for travel, family and low light, and you value stabilization over the extra brightness of f/1.4.

Tamron 17-70mm F2.8 Di III-A VC RXD: the stabilized f/2.8 zoom

The Tamron 17-70mm covers 17mm to 70mm, a 4.1x zoom ratio that Tamron calls class-leading for an APS-C standard zoom. It keeps its f/2.8 maximum aperture across the whole range. Tamron builds it from 16 elements in 12 groups, including two LD and three aspherical elements.

In Sony E-mount it weighs 525g and measures 119.3mm long, with a maximum diameter of 74.6mm.

Video features

Tamron says the 17-70mm is engineered to suppress focus breathing, so the frame does not visibly shift when you pull focus between subjects. Its RXD stepping motor is designed to be quiet, which helps when the camera microphone is recording. Imaging Resource lists it as compatible with camera features including Fast Hybrid AF and Eye AF, with Direct Manual Focus.

Close-ups and build

The minimum focus distance is 0.19m at the wide end and 0.39m at the telephoto end, which Tamron says helps with tabletop shots and blurred backgrounds. Imaging Resource lists a moisture-resistant construction and a fluorine coating.

Pick this lens if you want one zoom that replaces the kit lens for both photo and handheld video, and you can accept the weight.

Sigma 18-50mm F2.8 DC DN Contemporary: the light all-round upgrade

Digital Camera World names the Sigma 18-50mm f/2.8 DC DN Contemporary its best everyday lens for the A6400. Its reviewer, Rod, writes that he would pick it over Sony's 16-55mm f/2.8 G, which he describes as rather massive and expensive.

The Sigma offers a constant f/2.8 aperture and a classic 3x zoom range. Rod describes it as smaller than you would expect for a constant-aperture zoom, with very good build quality and weather resistance. In his use, the autofocus was super-fast and virtually silent, and he was impressed by the image quality.

The evidence for this lens does not list optical stabilization. That makes it a better fit if you shoot in good light, use a tripod for slow exposures, or put the camera on a gimbal for video. For handheld low-light work, the Tamron's VC gives you more margin.

Pick this lens if you want a bright zoom that keeps the a6400 small and you are comfortable managing your shutter speed.

Sigma 30mm F1.4 DC DN Contemporary: background blur and low light

Sigma designed the 30mm F1.4 DC DN to be extremely compact for small mirrorless bodies. Its f/1.4 aperture is the brightest in this guide, and Sigma says it makes possible a shallow depth of field for a soft, blurred background.

Sigma says the focus group design gives fast, smooth autofocus for video, and that the lens fully accommodates the Fast Hybrid AF of Sony E-mount cameras. According to Sigma, face recognition AF keeps focus on faces even as subjects move. Sigma also says its Super Multi-Layer Coating reduces flare and ghosting in backlit scenes, and the lens comes with an extra-long hood.

The trade-off is stabilization. The Imaging Resource user review of the Sony 35mm suggests the Sigma 30mm is worth a look for its faster aperture, while noting it has no stabilizer. On a body without in-body stabilization, that puts the job of preventing shake blur on your shutter speed.

Pick this lens if background blur and dim indoor light are your main goals. For more on how aperture and distance combine, see the Sony a6400 background blur guide.

Shutter speed for sharp handheld shots

Shutter speed is your main defense against blur when the lens has no stabilizer. A faster shutter speed gives your hands less time to move during the exposure.

Sigma's own sample shot from the 30mm on an α6000 used 1/320s at f/1.4 and ISO 100 in Aperture Priority. That is a comfortably fast speed in daylight. As light drops, a bright aperture like f/1.4 or f/1.8 lets you keep the shutter speed up without pushing ISO as high.

A practical way to find your own limit:

• Set Shutter Priority and take a few frames of a still subject at a fast speed.
• Step the shutter speed slower, shooting a few frames at each setting.
• Zoom in on playback and note the speed where your frames start to soften.
• Stay one or two steps faster than that speed whenever you shoot handheld with an unstabilized lens.

Longer focal lengths magnify shake, so repeat the test at the long end of a zoom. With a stabilized lens like the Tamron 17-70mm or Sony 35mm, you can usually go slower than with the Sigmas, which is the situation Tamron describes for indoor, twilight and night shooting. If your shots still come out soft, the Sony a6400 blurry photos guide walks through the settings that fix them. The Sony a6400 low light settings guide covers ISO and slow-shutter choices in more depth.

Filter sizes

Screw-on filters must match the thread size on the front of your lens. A polarizer (PL) and an ND filter are the two most useful for photo and video.

Tamron says most of its mirrorless lenses feature a 67mm filter size, which lets you share expensive PL or ND filters across lenses. Thread sizes vary between brands and models, so look up the exact size on each maker's spec page before you order. If you plan to own two lenses, choosing models with the same thread size saves you from buying every filter twice.

Which one to buy

Match the lens to how you shoot most of the time:

• Handheld video and mixed photo work, one lens only: Tamron 17-70mm F2.8, for its stabilization, wider zoom range and quiet autofocus.
• Small, stabilized prime for travel and low light: Sony E 35mm F1.8 OSS.
• Lightest f/2.8 zoom, good light or gimbal: Sigma 18-50mm F2.8 DC DN.
• Maximum background blur and dim rooms: Sigma 30mm F1.4 DC DN.

A common pairing is one zoom plus one prime. The zoom handles general shooting and the prime covers low light and portraits. For more on mixing brands, see whether third-party lenses are worth it for Sony shooters.

After your first upgrade

Once you have a better standard lens, Digital Camera World's A6400 guide points to a few lenses for specific jobs:

• More reach in one lens: the Sony E 18-135mm f/3.5-5.6 OSS, which the guide calls practically a superzoom that holds its performance at the long end.
• Vlogging and interiors: the Sony E PZ 10-20mm f/4 G, with a power zoom suited to video, or the older stabilized E 10-18mm f/4 OSS.
• Wildlife and sports reach: the Sony E 70-350mm f/4.5-6.3 G OSS, with a 105-525mm equivalent range and OSS.
• Street and close-ups: the Tamron 20mm f/2.8 Di III OSD M 1:2, which frames like 30mm on the A6400 and offers 1:2 close-up capability.

Several of these include stabilization, which keeps your handheld options open as you add lenses.