The Sony 400mm f/2.8 GM and the 600mm f/4 GM are both professional super-telephoto primes. The 400mm f/2.8 gathers more light and suits fast sports in poor light, while the 600mm f/4 reaches farther and suits distant wildlife. They are specialist tools, so the right choice follows your subject distance.
What Each Lens Is For
The 400mm f/2.8 is the classic sports lens. Its very wide aperture supports fast shutter speeds under stadium lights and renders strong background separation, and its focal length frames field sports well from the sidelines.
The 600mm f/4 is the classic wildlife lens. The extra reach brings distant birds and animals closer, and f/4 is still bright enough for early and late light.
Key Differences
| Trait | 400mm f/2.8 GM | 600mm f/4 GM |
|---|---|---|
| Reach | Shorter | Longer |
| Aperture | f/2.8, brighter | f/4, one stop slower |
| Main users | Sports, news, events | Wildlife, birding, motorsport |
| Handling | Heavy, sideline work | Heavy, usually used on a support |
Both are large, heavy lenses. Check the maker’s page for weight, minimum focus distance and teleconverter support before you commit.
How to Choose
- Subject distance: if you can usually get within reasonable range, 400mm is easier to compose. If subjects stay far away, 600mm is the better tool.
- Light: evening games and indoor arenas reward f/2.8. Daylight wildlife is often fine at f/4.
- Teleconverters: a converter extends reach at the cost of light. Check which converters each lens supports and how it affects autofocus.
- Support: a monopod, gimbal head or tripod is normal for both. Plan for the weight.
- Travel: these lenses need dedicated cases and often airline planning, so consider how often you will move them.
As general guidance, a shutter speed of roughly 1/1000 or faster helps freeze most sports and bird action at these lengths.
Who Should Choose Which
- Choose the 400mm f/2.8 if you shoot night games, indoor events or fast sports where light is limited.
- Choose the 600mm f/4 if you shoot wildlife or birds and need more distance.
- Consider renting before a large commitment so you can test the weight on a real outing.
FAQ
Can I use a teleconverter on the 400mm to get near 600mm?
Yes, with a compatible converter you gain reach, but you lose some light and may see a small drop in autofocus performance. The 600mm native lens remains a different tool.
Are these lenses practical for hobbyists?
They are designed for professional workloads. Many hobbyists find lighter zooms more practical, though renting these primes for special trips is common.
The Short Version
The 400mm f/2.8 is the brighter sports lens, and the 600mm f/4 is the longer wildlife lens. Choose by your usual distance and lighting, and confirm current specs on the maker’s page.
