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Sony made a big leap in technology, but no one is talking about it

Sony has created what could be called a game changer for cameras with its current flagship Sony a1. Although this camera offers a number of new features that most reviews rave about. This feature is to speed up the flash sync speed to his 1/400 second shutter speed.

The Sony a1 is one of the best full-frame mirrorless cameras on the market. Not only can you shoot high resolution 50 megapixel files, but you can also capture this much resolution at 30 frames per second. It wasn’t until recently that we thought it was impossible to combine speed and high resolution based on current technology. You can have a high resolution camera that captures a lot of detail, or a low resolution camera that shoots very fast in high speed situations. Sony was able to do both in one camera.

Additionally, Sony has managed to squeeze 8K 30p and 4K 120p into a 4:2:2, 10-bit recording. Basically the Sony a1 is a great camera system. However, these features are obvious upgrades that are inevitable in the grand scheme of things: most people expected Sony to manufacture his 8K-capable camera system, but Sony No one expected to improve the shutter mechanism and sync speed of the Sony A1.

What is a focal plane shutter?

A focal plane shutter is basically a shutter mechanism found in almost all DSLR and mirrorless cameras. The focal plane shutter is inside the camera, in front of the camera sensor. A focal plane shutter has two parts, called the front curtain and the rear curtain.

After the front curtain is open and the sensor is full, the rear curtain is lowered and the shutter is closed. The time it takes for the shutter to open and close depends on the shutter speed.

The main advantage of focal plane shutters is their ability to manage higher shutter speeds than leaf shutter mechanisms (discussed below). Most high-end DSLR and mirrorless cameras can manage shutter speeds up to 1/8000s. This is considerably faster than leaf shutter cameras.

Another advantage of the focal plane shutter is that it works inside the camera. This means that virtually any type of lens can be attached and the shutter mechanism can be activated. You can also use a pinhole body cap on your camera and the shutter will work to expose the image.

The downside is that the focal plane shutter can only stay fully open up to a certain speed. For most cameras, this shutter speed is 1/200 second. Above this speed, the shutter blades do not fully open as they move down the sensor to expose the image. Increasing the shutter speed narrows the opening of the shutter. Unless you’re shooting with flash, this isn’t a big deal. If the shutter blade opening is smaller than the sensor, the entire sensor will not be exposed when the flash is triggered.

As you can see in the comparison above, when shooting faster than sync speed, most of the flash hits the shutter blade instead of the sensor. To solve this, you can use a feature called Fast Sync. In this mode, the flash fires multiple times at high speed to follow the shutter blades moving along the sensor. Unfortunately, this feature significantly reduces flash power and is less than ideal in many situations.

What is Leaf Shutter

Leaf shutters are relatively rare when it comes to camera systems. The biggest and most obvious difference between a leaf shutter and a focal plane shutter is that the leaf shutter operates inside the lens instead of the camera. This severely limits third-party compatibility. Another obvious difference is the construction of the leaf shutter.

The focal plane shutter moves in one direction (usually top to bottom) over the sensor. A leaf shutter opens and closes in a circular motion similar to the opening and closing of diaphragm blades. It is this design difference that makes the biggest difference. Unlike the focal plane shutter, the leaf shutter mechanism has no flash sync speed limit. A leaf shutter lens can be synchronized with the flash at any shutter speed you can manage.

For example, current Hasselblad lenses are able to sync the flash even at shutter speeds of 1/2000s without the need for fast sync mode. The downside of the leaf shutter is that the highest speed currently available is his 1/2000th of a second, which is considerably slower than his 1/8000th, which is the speed a focal plane shutter can achieve.

How did Sony manage this?

Camera shutter mechanisms generally operate with a spring-loaded system. A focal plane shutter camera loads and fires two curtains when the shutter button is pressed. Spring-loaded systems have worked very well in cameras for decades. However, this system has also not been updated for a long time.

Sony’s α1 equipped with a dual-drive focal plane shutter has appeared. The shutter mechanism of this camera works with a spring-loaded system and a magnetic system. The spring-loaded system is active at most shutter speeds, both fast and slow. The magnetic system is only active between shutter speeds of 1/320s and 1/400s.

These are the two fastest points at which the Sony a1 can sync the flash in full frame mode. A magnetic system allows the shutter curtain to move faster across the frame. The front curtain can open fast enough so that by the time the rear curtain is ready to close, the sensor is fully open for exposure.

This is the main difference. The magnet method allows the shutter curtain to move faster than the standard mechanism. That extra speed helps ensure that the full sensor is open for exposure, as opposed to the portion blocked by the shutter blades.

Why this is a big update

The Sony a1 is currently the only full-frame camera on the market that can sync with flash at a shutter speed of 1/400 second. That’s twice his speed for most full-frame cameras, including Canon and Nikon’s flagship systems. When shooting in APS-C mode, this sync speed can go even faster to his 1/500 second shutter. This kind of speed is on par with some leaf shutter lenses.

Interestingly, even with such a fast sync speed on the Sony a1, the camera’s shutter is durable for over 500,000 cycles. However, it’s important to mention that Sony has not disclosed a durability rating for the shutter mechanism when flash sync priority is enabled.

Nonetheless, for photographers who do a lot of work, this increased sync speed offers more real benefits than improved dynamic range or increased resolution.

Having a lot of resolution is great, but after a certain point, a few extra pixels makes little difference to how you shoot and the results you get. It’s flexible enough that adding a half stop doesn’t make much of a difference to your workflow. Features like megapixels and dynamic range might make great headlines, but broadly speaking, it’s just marketing. It is now possible to shoot with 100 million pixels or more even with a smartphone.

Increased sync speed makes a big difference in your workflow. Shoot at a faster shutter speed regardless of the type of flash you use. You can even delay the need for high-speed sync shooting entirely. This is especially useful when shooting in a controlled or studio-based environment.

For a long time, 1/200th of a second was probably the maximum shutter speed you could choose when shooting in a studio. Being able to shoot at faster shutter speeds in a controlled environment will most likely mitigate potential problems. For example, if you’re shooting a person, introducing motion into the shot reduces the likelihood of motion blur.

This is arguably one of the hardest and best technological leaps we’ve seen to achieve in a long time, and Sony should be applauded for achieving this.

final thoughts

This is a big step forward for working professionals, and the best thing is that it won’t take long for this feature to show up in cheap cameras. You may start to see synchronous speeds.

What’s unclear at this point is whether Sony can take this dual-drive mechanism further. It’s arguably fair to assume that the magnetic system could possibly manage even faster shutter speeds. It was probably a durability concern that limited the speed to 1/400th of a second.

Hopefully, we’re just the beginning of what’s possible with magnetic shutter drives. Sony’s upcoming flagship camera may even sync flashes at 1/1000th of a second.