The Sony a7 IV claims a maximum frame rate of 10 fps using both mechanical and electronic shutters with AF/AE tracking.
However, if you check the footnotes of the specs page on Sony’s UK site you’ll find the following statement:
Maximum continuous shooting speed is 6 fps when shooting uncompressed RAW / uncompressed RAW+JPEG images.
And on the Sony US site the specs include a footnote that states:
Up to 10 fps in continuous “Hi+” mode and up to 8 fps in continuous “Hi” mode. Maximum continuous shooting speed is reduced when shooting lossless or uncompressed RAW / RAW+JPEG images. Maximum fps will depend on camera settings. Sony test conditions.
So according to the UK site shooting uncompressed RAW / uncompressed RAW+JPEG images reduces the maximum frame rate to 6 fps. The US site does not give a number and just says that the maximum continuous shooting speed is reduced when shooting lossless or uncompressed RAW / RAW+JPEG images.
So to be perfectly clear about the maximum fps you can expect depending on the file format that you are shooting in and your shooting speed I’ve put together for the following table from my own tests.
Maximum FPS by File Format & Drive Speed
For these tests I used a 64 GB Sony SF-G Tough UHS-II memory card. I shot the tests using manual exposure and manual focus. I’ve also shot the same tests using AF-C and the Priority set to “Release” and the results were the same.
|Lossless Compressed RAW||6||6||6||3|
|JPEG Extra Fine||10||8||6||3|
|Uncompressed RAW + JPEG Extra Fine||6||6||6||3|
|Compressed RAW + JPEG Extra Fine||10||8||6||3|
|Lossless Compressed RAW + JPEG Extra Fine||6||6||6||3|
|HEIF (4:2:0) Extra Fine||10||8||6||3|
|HEIF (4:2:2) Extra Fine||10||8||6||3|
I also completed the same tests using a Sony CEA-G CFexpress Type-A 160GB memory card and the results were the same.
Priority Set in AF-C & FPS Speed
The Sony a7 IV has a setting in the AF/MF menu called “Priority Set in AF-C”. This basically allows you to set whether to release the shutter even if the subject is not in focus when continuous AF is activated and your subject is in motion. The setting you choose here can also impact your FPS speed.
There are three different settings to choose from:
- 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.
It’s important to note that “Balanced Emphasis” is the default setting for the a7 IV. So if for some reason such as poor lighting the a7 IV struggles to acquire focus, the maximum number of frames per second will drop.
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.
If you want to achieve the maximum frame rate of 10 fps when shooting in Hi+ mode you’ll need to shoot in either compressed RAW, JPEG or HEIF file format.
If you shoot in uncompressed RAW, lossless compressed RAW, uncompressed RAW + JPEG or lossless compressed RAW + JPEG then the maximum frames per second is reduced to 6 fps.
Priority Set in AF-C is set by default to “Balanced Emphasis”. This can also reduce the maximum fps possible depending on your shooting conditions and subject.
For further details on memory cards for the a7 IV please visit my Sony a7 IV Memory Card Guide where I’ve tested over 18 memory cards in camera and include buffer tests results for each card.