The three adapters you mention—LA-EA3, LA-EA4, and LA-EA5—all let you mount older Sony/Minolta A-mount lenses on newer E-mount mirrorless bodies, but they differ quite a lot in how autofocus is handled and what lenses they support.
🧩 Core idea (quick intuition)
- LA-EA3 → “dumb tube” (no AF motor, uses camera AF)
- LA-EA4 → “self-contained AF system” (mirror + dedicated AF module)
- LA-EA5 → “modern hybrid” (uses camera AF plus adds motor support)
🔍 Side-by-side comparison
| Feature | LA-EA3 | LA-EA4 | LA-EA5 |
|---|---|---|---|
| Autofocus system | Uses camera AF (on-sensor) | Built-in AF module + translucent mirror | Uses camera AF (on-sensor) |
| Built-in AF motor (for screw-drive lenses) | ❌ No | ✅ Yes | ✅ Yes |
| Works with SSM/SAM lenses (motorised lenses) | ✅ Yes | ✅ Yes | ✅ Yes |
| Works with older screw-drive lenses | ❌ No | ✅ Yes | ✅ Yes (only on supported bodies) |
| Eye AF / modern AF features | ✅ Yes (depends on camera) | ❌ No (limited, older AF system) | ✅ Yes (best support) |
| Light loss | ❌ None | ⚠️ Yes (translucent mirror) | ❌ None |
| AF coverage / tracking | Uses full sensor AF | Limited AF points (older system) | Uses full sensor AF |
| Size / design | Simple tube | Bulkier (mirror housing) | Compact |
Sources: Sony’s official comparison tables
📸 What actually matters in real use
1) Autofocus behaviour
- LA-EA3: relies entirely on your mirrorless camera’s AF → good for modern lenses, but no AF at all with screw-drive lenses.
- LA-EA4: has its own AF system (like an old DSLR) → works with all lenses, but AF is limited and dated.
- LA-EA5: best of both → uses modern on-sensor AF and supports screw-drive lenses (if your body supports it).
👉 In practice:
- EA4 = reliable but “old-school”
- EA3 = modern but limited compatibility
- EA5 = modern + broad compatibility (best if supported)
2) Lens compatibility
- SSM/SAM (motorised lenses) → all three work
- Older Minolta screw-drive lenses:
- EA3 ❌
- EA4 ✅
- EA5 ✅ (but only with newer bodies)
3) Image quality & light
- LA-EA4 loses light due to its translucent mirror (≈⅓ stop)
- EA3 & EA5 have no mirror → no light loss, cleaner imaging
4) Modern features (Eye AF, tracking, etc.)
- EA3 & EA5 can use your camera’s full AF features (Eye AF, tracking, etc.)
- EA4 cannot—it’s stuck with its internal AF module
🧠 Bottom line (how to choose)
- Go LA-EA3 if:
- You only use SSM/SAM lenses
- You want a simple, inexpensive adapter
- Go LA-EA4 if:
- You have older screw-drive lenses
- Your camera doesn’t support LA-EA5 fully
- You can tolerate older AF + slight light loss
- Go LA-EA5 if:
- You want the best autofocus performance
- You have mixed lenses (including screw-drive)
- You own a newer compatible Sony body
⚠️ One important caveat
The LA-EA5’s full capabilities depend heavily on the camera body—on older bodies it behaves more like an EA3.