Lens guide · Sony E-mount
The Best Lenses for the Sony a7 III
The a7 III launched in 2018 at $1,999 for the body, and was also sold as a kit with a 28-70mm zoom. This guide is about what to buy next — what each step up gains over the kit lens, what it adds to a 650g (1.43 lb) camera, and what it costs.
We haven't shot with these lenses for this guide, so we don't rate sharpness or autofocus. Picks are made on published specifications, which we checked against the makers' own spec pages. Some links go to Amazon; as an Amazon Associate we earn from qualifying purchases.
Quick picks
| For | Lens | Aperture | Lens weight | With a7 III | Launch price |
|---|---|---|---|---|---|
| Kit-lens upgrade | Tamron 28-75mm F/2.8 Di III VXD G2 Check price on Amazon | 28–75mm f/2.8 | 540g (1.19 lb) | 1190g (2.62 lb) | $799 |
| First prime | Sony FE 50mm f/1.8 Check price on Amazon | 50mm f/1.8 | 186g (6.6 oz) | 836g (1.84 lb) | $249 |
| Portrait | Sony FE 85mm f/1.8 Check price on Amazon | 85mm f/1.8 | 371g (13.1 oz) | 1021g (2.25 lb) | $599 |
| Video | Sony FE PZ 16-35mm f/4 G Check price on Amazon | 16–35mm f/4 | 353g (12.5 oz) | 1003g (2.21 lb) | $1,199 |
| Landscape | Tamron 17-28mm F/2.8 Di III RXD Check price on Amazon | 17–28mm f/2.8 | 420g (14.8 oz) | 1070g (2.36 lb) | $799 |
| Astro | Sony FE 20mm f/1.8 G Check price on Amazon | 20mm f/1.8 | 373g (13.2 oz) | 1023g (2.26 lb) | $899 |
| Telephoto | Tamron 50-300mm f/4.5-6.3 Di III VC VXD Check price on Amazon | 50–300mm f/4.5–6.3 | 665g (1.47 lb) | 1315g (2.90 lb) | $699 |
| One-lens travel | Sony FE 24-105mm f/4 G OSS Check price on Amazon | 24–105mm f/4 | 663g (1.46 lb) | 1313g (2.89 lb) | $1,399 |
What the a7 III itself changes about lens choice
- It weighs 650g (1.43 lb) with battery and SD card (Sony's figure). The chart below shows what each pick brings that to.
- Stabilisation is in the body: five-axis, rated at 5.0 stops at launch. Every lens is stabilised, so lens OSS is an addition, not a requirement — most picks here don't have it.
- 4K/24p uses the full sensor width; 4K/30p uses a cropped area (about 1.2×). At 30p a lens frames narrower than its focal length suggests — a 16mm frames like about 19mm. That matters for the video and vlogging picks below.
- APS-C lenses work, at reduced resolution: the camera switches to its APS-C crop, roughly 1/2.25 of the sensor area, so about 10MP instead of 24.2MP. Every lens in this guide covers full frame.
Sources: Sony α7 III help guide — specifications (weight); Wikipedia, Sony α7 III (stabilisation and 4K readout, citing DPReview's review).
Upgrading from the 28-70mm kit lens
The a7 III was sold as a kit with the Sony FE 28-70mm f/3.5-5.6 OSS — 295g (10.4 oz), f/3.5–5.6. The usual reason to replace it is light: at its long end it is f/5.6. An f/2.8 zoom gathers two-thirds of a stop more light at the wide end and two stops more at 70mm. The cost is weight and price — this table shows both.
| Lens | Range | Aperture | Light vs kit at long end | Weight | With a7 III | Price | Sealed |
|---|---|---|---|---|---|---|---|
| Sony FE 28-70mm f/3.5-5.6 OSS | 28–70mm | f/3.5–5.6 | — | 295g (10.4 oz) | 945g (2.08 lb) | $299 | — |
| Tamron 28-75mm F/2.8 Di III VXD G2 | 28–75mm | f/2.8 | +two stops | 540g (1.19 lb) | 1190g (2.62 lb) | $799 | Yes |
| Sigma 28-70mm f/2.8 DG DN Contemporary | 28–70mm | f/2.8 | +two stops | 470g (1.04 lb) | 1120g (2.47 lb) | $899 | Yes |
| Tamron 20-40mm f/2.8 Di III VXD | 20–40mm | f/2.8 | +two stops | 365g (12.9 oz) | 1015g (2.24 lb) | $699 | Yes |
| Sony FE 24-50mm f/2.8 G | 24–50mm | f/2.8 | +two stops | 440g (15.5 oz) | 1090g (2.40 lb) | $1,099 | Yes |
| Sigma 24-70mm f/2.8 DG DN II Art | 24–70mm | f/2.8 | +two stops | 735g (1.62 lb) | 1385g (3.05 lb) | $1,199 | Yes |
| Sony FE 24-105mm f/4 G OSS | 24–105mm | f/4 | +one stop | 663g (1.46 lb) | 1313g (2.89 lb) | $1,399 | Yes |
| Sony FE 24-70mm f/2.8 GM II Lens | 24–70mm | f/2.8 | +two stops | 695g (1.53 lb) | 1345g (2.97 lb) | $2,298 | Yes |
28–75mmf/2.8540g (1.19 lb)117.6mm (4.6 in) long$799
On the a7 III: 1190g (2.62 lb)
Our pick: Tamron 28-75mm F/2.8 Di III VXD G2. 28–75mm at a constant f/2.8 for $799, 540g (1.19 lb), with Tamron's moisture-resistant construction. It keeps (and slightly extends) the kit lens's range while gaining two stops at the long end — and of the 9 constant-f/2.8 zooms in our E-mount data that reach 70mm, it has the lowest launch price. The trade-off: it weighs 245g (8.6 oz) more than the kit lens.
- Lighter: the Sigma 28-70mm f/2.8 DG DN Contemporary is 470g (1.04 lb) for $899, stopping at 70mm.
- Wider: the Tamron 20-40mm f/2.8 Di III VXD starts at 20mm and is 365g (12.9 oz), but ends at 40mm.
- More reach, constant f/4: the Sony FE 24-105mm f/4 G OSS goes to 105mm with optical stabilisation, at 663g (1.46 lb).
- The G Master several lists lead with: the Sony FE 24-70mm f/2.8 GM II Lens is $2,298 — $1,499 more than the Tamron. Some older lists still recommend the first-generation 24-70mm GM, which the Mark II replaced in 2022.
What each pick adds to the a7 III
- First primeSony FE 50mm f/1.8836g (1.84 lb)
- Kit lensSony FE 28-70mm f/3.5-5.6 OSS945g (2.08 lb)
- VideoSony FE PZ 16-35mm f/4 G1003g (2.21 lb)
- PortraitSony FE 85mm f/1.81021g (2.25 lb)
- AstroSony FE 20mm f/1.8 G1023g (2.26 lb)
- LandscapeTamron 17-28mm F/2.8 Di III RXD1070g (2.36 lb)
- Kit-lens upgradeTamron 28-75mm F/2.8 Di III VXD G21190g (2.62 lb)
- One-lens travelSony FE 24-105mm f/4 G OSS1313g (2.89 lb)
- TelephotoTamron 50-300mm f/4.5-6.3 Di III VC VXD1315g (2.90 lb)
- Often recommendedSony FE 24-70mm f/2.8 GM II Lens1345g (2.97 lb)
Best first prime: Sony FE 50mm f/1.8
50mmf/1.8186g (6.6 oz)59.5mm (2.3 in) long$249
On the a7 III: 836g (1.84 lb)
$249 and 186g (6.6 oz). f/1.8 gathers 3⅓ stops more light than the kit lens at its long end, and on full frame a wide aperture gives a shallow depth of field — the usual first reason to buy a prime.
Every full-frame autofocus E-mount lens in our data that launched under $500:
| Lens | Focal | Aperture | Weight | Price | Sealed |
|---|---|---|---|---|---|
| Viltrox AF 14mm f/4.0 AIR | 14mm | f/4 | 170g (6.0 oz) | $199 | Yes |
| Sony FE 50mm f/1.8 | 50mm | f/1.8 | 186g (6.6 oz) | $249 | — |
| Viltrox AF 85mm f/2.0 EVO | 85mm | f/2 | 340g (12.0 oz) | $275 | Yes |
| Sony FE 28-70mm f/3.5-5.6 OSS | 28–70mm | f/3.5–5.6 | 295g (10.4 oz) | $299 | — |
| Samyang AF 18mm f/2.8 FE | 18mm | f/2.8 | 128g (4.5 oz) | $299 | — |
| Samyang AF 45mm f/1.8 FE | 45mm | f/1.8 | 162g (5.7 oz) | $299 | — |
| Viltrox AF 26mm f/2.8 EVO | 26mm | f/2.8 | 130g (4.6 oz) | $299 | — |
| Samyang AF 16mm f/2.8 P FE | 16mm | f/2.8 | 225g (7.9 oz) | $349 | — |
| Viltrox AF 55mm f/1.8 EVO | 55mm | f/1.8 | 370g (13.1 oz) | $370 | Yes |
| Viltrox AF 35mm f/1.8 II EVO | 35mm | f/1.8 | 355g (12.5 oz) | $395 | Yes |
| Samyang AF 85mm f/1.8 P FE | 85mm | f/1.8 | 490g (1.08 lb) | $399 | — |
| Samyang AF 75mm f/1.8 FE | 75mm | f/1.8 | 232g (8.2 oz) | $399 | — |
| Viltrox AF 85mm f/1.8 II FE | 85mm | f/1.8 | 464g (1.02 lb) | $449 | — |
| Sony FE 28mm f/2 | 28mm | f/2 | 200g (7.1 oz) | $449 | — |
| Sony FE 28-60mm f/4-5.6 | 28–60mm | f/4–5.6 | 167g (5.9 oz) | $499 | — |
| Sigma 50mm f/2 DG DN Contemporary | 50mm | f/2 | 290g (10.2 oz) | $499 | — |
| Sony FE 50mm f/2.8 Macro | 50mm | f/2.8 | 236g (8.3 oz) | $499 | — |
For a wider everyday view, the Sony FE 28mm f/2 is $449 and 200g (7.1 oz).
Best portrait lens: Sony FE 85mm f/1.8
85mmf/1.8371g (13.1 oz)82mm (3.2 in) long$599
On the a7 III: 1021g (2.25 lb)
85mm at f/1.8 for $599, 371g (13.1 oz), dust- and moisture-resistant. The longer focal length lets you stand back for a head-and-shoulders frame, and the wide aperture separates the subject from the background.
- Faster: the Sigma 85mm F1.4 DG DN Art gains two-thirds of a stop (f/1.4) for $1,099, at 625g (1.38 lb).
- Cheaper: the Viltrox AF 85mm f/2.0 EVO is $275 at f/2, 340g (12.0 oz).
Best for video: Sony FE PZ 16-35mm f/4 G
16–35mmf/4353g (12.5 oz)88.1mm (3.5 in) long$1,199
On the a7 III: 1003g (2.21 lb)
A motorised power zoom (the "PZ") at a constant f/4, so exposure stays the same as you zoom; 353g (12.5 oz), weather-sealed. Because 4K/30p on the a7 III is cropped about 1.2×, the 16mm end frames like about 19mm at 30p — still wide enough for arm's-length vlogging, which a 28mm kit lens (about 34mm at 30p) is not.
The Tamron 20-40mm f/2.8 Di III VXD is the cheaper, brighter alternative (f/2.8, $699), framing like about 24mm at 30p. Shooting 4K/24p avoids the crop entirely.
Best for landscape: Tamron 17-28mm F/2.8 Di III RXD
17–28mmf/2.8420g (14.8 oz)99mm (3.9 in) long$799
On the a7 III: 1070g (2.36 lb)
17–28mm at f/2.8 for $799, 420g (14.8 oz), with a 67mm filter thread and Tamron's moisture-resistant construction.
| Lens | Range | Aperture | Weight | Filter | Price | Sealed |
|---|---|---|---|---|---|---|
| Tamron 17-28mm F/2.8 Di III RXD | 17–28mm | f/2.8 | 420g (14.8 oz) | 67mm | $799 | Yes |
| Sigma 16-28mm f/2.8 DG DN Contemporary | 16–28mm | f/2.8 | 450g (15.9 oz) | 72mm | $899 | — |
| Sony FE PZ 16-35mm f/4 G | 16–35mm | f/4 | 353g (12.5 oz) | 72mm | $1,199 | Yes |
The Sigma 16-28mm f/2.8 DG DN Contemporary starts wider at 16mm (450g (15.9 oz), $899). Sigma's spec page for it doesn't describe weather sealing, so we don't mark it as sealed.
Best for astrophotography: Sony FE 20mm f/1.8 G
20mmf/1.8373g (13.2 oz)84.7mm (3.3 in) long$899
On the a7 III: 1023g (2.26 lb)
Night-sky work wants a wide focal length and a wide aperture: 20mm at f/1.8 gathers 1⅓ stops more light than an f/2.8 zoom, for $899 at 373g (13.2 oz).
Every full-frame autofocus E-mount prime in our data at 24mm or wider with f/2 or brighter:
| Lens | Focal | Aperture | Weight | Price |
|---|---|---|---|---|
| Sony FE 14mm f/1.8 GM | 14mm | f/1.8 | 460g (1.01 lb) | $1,499 |
| Sigma 14mm f/1.4 DG DN Art | 14mm | f/1.4 | 1160g (2.56 lb) | $1,599 |
| Sony FE 16mm f/1.8 G | 16mm | f/1.8 | 394g (13.9 oz) | $1,099 |
| Sony FE 20mm f/1.8 G | 20mm | f/1.8 | 373g (13.2 oz) | $899 |
| Sigma 20mm f/1.4 DG DN Art | 20mm | f/1.4 | 630g (1.39 lb) | $999 |
| Sigma 20mm f/2 DG DN Contemporary | 20mm | f/2 | 370g (13.1 oz) | $549 |
| Sony FE 24mm f/1.4 GM | 24mm | f/1.4 | 445g (15.7 oz) | $1,399 |
| Sigma 24mm f/1.4 DG DN Art | 24mm | f/1.4 | 510g (1.12 lb) | $999 |
| Samyang AF 24mm f/1.8 FE | 24mm | f/1.8 | 213g (7.5 oz) | $599 |
| Sigma 24mm f/2 DG DN Contemporary | 24mm | f/2 | 360g (12.7 oz) | $549 |
Best telephoto: Tamron 50-300mm f/4.5-6.3 Di III VC VXD
50–300mmf/4.5–6.3665g (1.47 lb)150mm (5.9 in) long$699
On the a7 III: 1315g (2.90 lb)
Reaches 300mm for $699 at 665g (1.47 lb) — the lightest lens that reaches 300mm in our E-mount data, with optical stabilisation. It also focuses close: 0.5× at the wide end, per Tamron.
- Constant f/2.8: the Tamron 70-180mm F/2.8 Di III VC VXD G2 — 855g (1.88 lb), $999, with stabilisation.
- 400mm on a budget: the Sigma 100-400mm f/5-6.3 DG DN OS Contemporary — $759, but 1140g (2.51 lb).
The a7 III shoots up to about 10 frames per second (Sony's figure), which sets the pace for action.
Best one-lens travel zoom: Sony FE 24-105mm f/4 G OSS
24–105mmf/4663g (1.46 lb)113.3mm (4.5 in) long$1,399
On the a7 III: 1313g (2.89 lb)
24–105mm at a constant f/4, with optical stabilisation, 663g (1.46 lb), dust- and moisture-resistant. Against the kit lens it adds 35mm of reach and one stop at the long end, for $1,399.
Questions
Is the 28-70mm kit lens worth keeping?
At 295g (10.4 oz) it is lighter than every upgrade zoom in the table above. What it gives up is light — f/3.5–5.6 against f/2.8 for the f/2.8 upgrades.
Can I use Canon EF lenses on the a7 III?
Yes, with an adapter — for example Sigma's MC-11 or Metabones' EF-to-E adapters. Autofocus support depends on the adapter and lens combination, so check the adapter maker's compatibility list before buying. This guide only covers native E-mount lenses.
Do I need a lens with OSS?
No — the a7 III's in-body stabilisation works with any lens; lens OSS is an addition, not a requirement.
Which lens for video on the a7 III?
Something that starts wide, because 4K/30p crops about 1.2× — see video.
How we chose
- Search intent first. a7 III searches lean toward budget, first lenses and replacing the kit lens, then video, landscape, astro and portrait — so this guide is ordered that way.
- Specs, not impressions. We haven't tested these lenses for this guide and don't claim one is sharper or focuses faster.
- Checked against the makers. Third-party specs used here were re-checked against Sigma's and Tamron's own spec pages on October 26, 2026; body facts are cited above.
- Prices are launch prices (MSRP) in US dollars. Street and used prices vary.
- Weights are manufacturer figures; the body is weighed with battery and SD card: 650g (1.43 lb).