The Sony a1 claims a maximum frame rate of 30 fps using the electronic shutter with AF/AE tracking.
However, in order actually achieve 30 fps there are some pretty stringent prerequisites that will need to be met.
This article takes a look at these prerequisites and I also test the fps speed with each file type and drive mode.
Prerequisites for 30 FPS with Autofocus Continuous (AF-C)
- You need to be shooting in Compressed Raw, JPEG or HEIF file format.
- Focus mode should be set to AF-C and drive mode to Hi+.
- Electronic shutter speed between 1/250 – 1/32000 sec.
- Priority Set in AF-C set to ‘Release’. The default is ‘Balanced Emphasis’. With it set to ‘Release’ the shutter will be released even if the subject is out of focus. With ‘Balanced Emphasis’ the camera tries to achieve a balance between focus and shutter release, however this reduces the maximum FPS slightly.
- Use a focus mode other than tracking. If any of the tracking focus modes are used then you will not achieve the maximum FPS.
- Have the latest lens firmware version installed.
- A compatible lens.
Maximum FPS by File Format & Drive Speed
For these tests I used a Sony CEA-G CFexpress Type-A 160GB memory card. To avoid any possibility of slowing down the fps these tests were shot in manual mode with manual focus.
|Lossless Compressed RAW||20||20||15||5|
|JPEG Extra Fine||30||20||15||5|
|Uncompressed RAW + JPEG Extra Fine||20||20||15||5|
|Compressed RAW + JPEG Extra Fine||30||20||15||5|
|Lossless Compressed RAW + JPEG Extra Fine||20||20||15||5|
|HEIF (4:2:0) Extra Fine||30||20||15||5|
|HEIF (4:2:2) Extra Fine||30||20||15||5|
Just like Sony says, only Compressed Raw, JPEG or HEIF file formats are capable of achieving the maximum frame rate of 30 fps.
Priority Set in AF-C & FPS Speed
The Sony a1 has a setting in the AF/MF menu called “Priority Set in AF-C”. This allows you to set whether to release the shutter even if your subject is not in focus. However, the setting you choose here can also impact your FPS speed.
There are three different settings:
- AF: Prioritizes focusing.
- Release: Prioritizes the shutter’s release. The shutter will be released even if the subject is out of focus.
- Balanced Emphasis (default): Shoots with a balanced emphasis on both focusing and shutter release.
Balanced Emphasis is the default setting for the a1. So if for some reason such as poor lighting the a1 struggles to acquire focus, the maximum number of frames per second will drop when using balanced emphasis.
If you change this setting to Release it will fire the shutter even if the shot is out of focus, but I wouldn’t recommend this except for in a few situations.