A lightweight super-telephoto prime for birds, wildlife, and fast-moving subjects
Introduction
For most of my wildlife photography, I use a 200–600mm zoom.
I've always appreciated the flexibility of being able to react when an animal moves closer, suddenly changes direction, or appears somewhere I wasn't expecting. Wildlife rarely follows the plan you have in your head.
So switching to a fixed 400mm lens changes the way I photograph.
I recently had the opportunity to field-test the new Sony FE 400mm F4.5 GM OSS, photographing birds, birds in flight, and larger wildlife in the same types of real-world situations where I normally use my 200–600mm.
There were a few things I expected from a G Master prime: sharpness, fast autofocus, and great subject separation.
What I didn't expect was just how light it would feel.
At approximately 994 grams, the 400mm F4.5 weighs under one kilogram, and that became one of the most important parts of my experience with it.
Why I Like 400mm for Wildlife
I've always considered 600mm close to the ideal focal length for small birds.
But wildlife isn't always small.
For larger birds and mammals, 400mm gives me a little more room to work with the subject and its environment.
That extra space can also become valuable when something starts moving.
A large bird flying toward me can quickly become difficult to keep in the frame at 600mm. At 400mm, I have more freedom to follow it and react to changes in direction.
The same applies to larger wildlife. Rather than filling the entire frame with the animal, I can decide whether I want a tight portrait or whether some of the landscape should become part of the photograph.
For birds, 600mm feels like the perfect focal length. For larger birds and wildlife, 400mm gives me a little more freedom to react and compose.
The First Thing I Noticed: The Weight
The weight was probably the biggest surprise.
A 400mm G Master prime sounds like equipment that should require a monopod or become tiring after a long period of handheld shooting.
This didn't feel that way.
Sony has kept the lens below one kilogram and positioned the centre of gravity toward the camera body to improve balance and handling.
That makes a meaningful difference when you're actually outside photographing wildlife.
I spend a lot of time walking with my camera ready. When I find a bird, I may then spend another extended period holding the camera up, waiting for a behaviour or a particular moment.
A few hundred grams might not seem dramatic when looking at specifications.
After hours in the field, it absolutely is.
Handholding a 400mm Prime
The lightweight construction also changed how I could use the lens.
Rather than treating it like a large super-telephoto that needed to remain supported, I could move around with it and shoot handheld.
That is particularly important for birds in flight.
When a bird changes direction unexpectedly, I want to be able to rotate, reposition and follow it without fighting the equipment.
The 400mm felt remarkably balanced in those situations.
Instead of thinking about the lens, I could concentrate on keeping the bird in the frame.
That's exactly what I want wildlife equipment to do.
F4.5 in Changing Light
The other advantage of this particular 400mm is its F4.5 maximum aperture.
Wildlife photographers spend a surprising amount of time working in poor light.
Birds disappear into forests. Clouds move in. The best activity can happen early in the morning or late in the evening.
That extra light becomes useful when I'm trying to maintain a fast shutter speed without pushing ISO unnecessarily high.
It's also part of what gives the lens its subject separation.
When the bird is positioned well away from the background, the combination of 400mm and F4.5 can create a beautifully clean image.
Sharpness and Bokeh
The image quality was exactly what I hoped to see.
Fine feather detail remained sharp, while backgrounds could become extremely smooth.
Sony uses three Super ED elements and one ED element in the optical design, along with an 11-blade circular aperture. The lens is also individually calibrated to help produce the smooth bokeh associated with the G Master line.
In the field, the result I cared about was much simpler:
The bird stood out.
A wildlife lens needs to resolve tiny details, but I think the quality of everything around the animal matters almost as much.
A distracting background can ruin an otherwise technically perfect photograph.
With the 400mm, I was consistently impressed by how clean those backgrounds could become.
Birds in Flight
Birds in flight are one of my favourite ways to test any wildlife lens.
They're unpredictable.
Speed changes constantly.
The subject can move toward you, away from you, or across the frame within seconds.
And sometimes you have almost no warning before the bird takes off.
The autofocus performance of the 400mm was excellent during these situations.
Both new lenses use two XD Linear Motors, with one driving each focus group, and they're designed specifically around rapidly moving and irregular subjects such as birds, wildlife, and sports.
That translated well into actual bird photography.
The autofocus reacted quickly, stayed connected to the bird, and allowed me to spend more attention on timing and composition.
Birds in flight are one of the best tests of any wildlife lens. The autofocus responded quickly, stayed with the subject and allowed me to concentrate on timing and composition.
Full-Time DMF
One feature I appreciated more than I expected was Full-time DMF.
It allows manual focus override while autofocus is active, without requiring me to stop and switch focusing modes.
Wildlife doesn't always appear in a clean opening.
A bird might be sitting behind a branch or surrounded by grasses where autofocus has several possible targets.
Being able to immediately make a manual adjustment and then continue shooting is a small feature that becomes very useful in those moments.
Again, it reduces the amount of time I'm thinking about the equipment.
Adding the 1.4× Teleconverter
This is where the 400mm became particularly interesting for me as a bird photographer.
The lens supports Sony's 1.4× and 2.0× teleconverters. With the 1.4× teleconverter, the 400mm becomes a 560mm F6.3.
560mm is very close to the 600mm focal length I already love for birds.
That gives me an interesting combination.
I can use 400mm F4.5 when I'm photographing larger wildlife, larger birds, or working in lower light.
Then I can add the 1.4× teleconverter when I need more reach for smaller birds.
Suddenly I have 560mm.
For me, that's what makes this lens considerably more versatile than the focal length initially suggests.
What I Missed From My 200–600mm
There is one unavoidable tradeoff.
It's a prime.
With my 200–600mm, if a bird suddenly flies toward me, I can pull back from 600mm to 400mm or 300mm almost instantly.
With the 400mm, my feet become the zoom.
And wildlife doesn't always give you the opportunity to move.
There were moments where I missed that flexibility.
But the tradeoff is an incredibly lightweight, balanced lens with fast autofocus, excellent image quality, F4.5 light gathering and beautiful subject separation.
Whether that trade makes sense depends heavily on what you're photographing.
Who I Think the 400mm F4.5 GM Is For
I see the 400mm as the more versatile wildlife lens of these two new primes.
It makes a lot of sense for larger birds, birds in flight, mammals and situations where subjects may approach unexpectedly.
The 1.4× teleconverter also changes the equation considerably for bird photographers by providing 560mm F6.3 when more reach is required.
It's particularly interesting for photographers who want prime-lens performance but don't want the physical burden normally associated with carrying a super-telephoto prime all day.
Conclusion
After field-testing the Sony FE 400mm F4.5 GM OSS, the thing I kept coming back to was how easy it was to use.
The image quality was excellent.
The autofocus was fast.
The F4.5 aperture gave me additional light and beautiful separation.
But the weight and balance are what changed the experience.
A great wildlife lens shouldn't make me think about carrying a great wildlife lens.
It should let me concentrate on the bird, anticipate what's going to happen next, and react when the moment arrives.
That's what I enjoyed about the 400mm.
"The 400mm is the versatile wildlife lens. It gives me room to react, and with the 1.4× teleconverter, I can get very close to my favourite focal length for birds."
– Jared VanderMeer
