Comparison
Sony A7 III vs. A7 IV: few reasons to upgrade when buying used
I compare the Sony A7 III and A7 IV from a used buyer's perspective. When is the newer model worth the extra money, and when should you stick with the proven A7 III?
The Sony A7 III is still a very solid body today, and on the used market you can get one for a fraction of the price of a new one. The A7 IV is better in many respects – but the question is whether the difference is big enough in practice to justify paying more.
Sensor and resolution
The A7 III has 24.2 MP, the A7 IV 33 MP. Higher resolution gives you more room for cropping, large-format printing and demanding retouching. If you shoot landscapes or portraits and every detail matters to you, those extra 9 MP or so are noticeable.
For most everyday needs, though, including social media and standard prints, the A7 III is plenty. In dynamic range and high-ISO noise, the differences between the two bodies are small – certainly not as dramatic as between the A7 II and A7 III.
Autofocus: a leap, or just an improvement?
This is where it gets interesting. The A7 III had great autofocus for its time, but the A7 IV introduced newer real-time subject tracking. Eye, head and body detection is faster and more reliable, especially with moving subjects, animals and sports.
If you shoot athletes, birds or kids who won't sit still, the A7 IV won't let you down. The A7 III is still capable, but it loses fast-moving subjects more often. With static portraits and landscapes, the difference is less noticeable. The A7 IV also has a new, clearer menu system, which makes it easier to use.
Video: this is where the A7 IV leads
If you plan to shoot video, the A7 IV is the clear choice:
- 4K 60p (with a crop) in 10-bit 4:2:2, which you'll appreciate when color grading and editing
- more effective stabilization
- better heat management during long takes
The A7 III shoots 4K 30p, but only in 8-bit – that will hold you back for more demanding video. If you only shoot stills, though, the video specs may not matter to you.
When to upgrade and when not to
Upgrading to the A7 IV makes sense when
- you shoot video often and need 10-bit and 4K 60p
- you shoot sports, wildlife or action and need more reliable autofocus
- you need higher resolution for printing or cropping
- you have the budget and want a body that will last you several years
Stick with the A7 III when
- you mostly shoot static scenes (landscapes, portraits, architecture)
- your A7 III works reliably and the autofocus isn't holding you back
- you're looking for the best value for money and want to put the savings into a better lens
- you don't plan to shoot demanding video
Conclusion
The Sony A7 III is still a great camera – you can get one at a good price on the used market, and it takes excellent photos. The A7 IV is better in almost every way, but the gap isn't as big as it was with the previous generation.
If you're happy with your A7 III, there's no need to rush. But if resolution, autofocus or video is holding you back, the A7 IV is a sensible investment. Often, though, money spent on a lens does more than a body upgrade.
Fotoaparát
Sony A7 III