Drop an .ARW file from your Sony Alpha A77 II (ILCA-77M2) and get the exact mechanical shutter actuation count in seconds — processed entirely in your browser, never uploaded anywhere.
Check Shutter Count →The Sony Alpha A77 II (2014) was Sony’s final flagship APS-C SLT camera. Using Single Lens Translucent (SLT) technology, the A77 II replaced the traditional moving mirror with a fixed, semi-transparent pellicle mirror that simultaneously directs light to both the sensor and a dedicated phase-detect AF module. This enabled continuous 12 fps shooting with full AF tracking — unprecedented for an APS-C camera at launch.
The 24.3 MP Exmor APS-C sensor, 79-point phase-detect AF system (all cross-type), and weather-sealed magnesium alloy body made the A77 II a serious sports and wildlife tool. The mechanical shutter is rated at 150,000 actuations.
| Camera | Type | Sensor | Rated Shutter | ARW Tag |
|---|---|---|---|---|
| Sony Alpha A77 II | SLT A-mount | 24.3 MP APS-C | 150,000 | 0x9050 |
| Sony A6700 (E-mount successor class) | Mirrorless | 26 MP APS-C | 150,000 | 0x9050 |
| Sony A9 (sports successor) | Mirrorless | 24.2 MP FF | 500,000 | 0x9050 |
The A77 II ARW file uses the same encrypted MakerNote structure as Sony’s E-mount cameras. ShutterCount decrypts the cubic residue cipher (modulo 249) entirely in your browser.
| Shutter Count | % of Rated Life | Assessment |
|---|---|---|
| 0 – 10,000 | < 7 % | Very low use — near new |
| 10,000 – 50,000 | 7 – 33 % | Normal use for casual shooter |
| 50,000 – 100,000 | 33 – 67 % | Moderate to heavy use |
| 100,000 – 130,000 | 67 – 87 % | Heavy use — negotiate price |
| 130,000 + | 87 %+ | Near or past rated life |
The A77 II’s 12 fps burst mode means sports and wildlife photographers could accumulate 150,000 actuations in 208 minutes of continuous shooting. Always verify the count via an original ARW file when buying. A used A77 II with under 30,000 actuations likely served a portrait or travel photographer rather than a sports shooter.
The Sony A77 II stores the mechanical shutter count in ARW MakerNote EXIF tag 0x9050. Like all Sony Alpha cameras — both A-mount SLT and E-mount mirrorless — the value is encrypted using a cubic residue cipher (modulo 249). ShutterCount decrypts and reads this value entirely in your browser.
JPEGs from the A77 II do not contain the encrypted MakerNote data needed to read the shutter count. Always use the original .ARW raw file for an accurate reading.
SLT (Single Lens Translucent) uses a fixed semi-transparent mirror to split light between the sensor and the phase-detect AF array. Unlike a conventional DSLR mirror that flips up for each exposure, the SLT mirror never moves. This means the mechanical shutter is the sole mechanical wear component — every shot, including live view and burst frames at 12 fps, increments the shutter counter. The advantage is near-silent shooting with no mirror vibration.
For photographers with a Minolta or Sony A-mount lens collection, yes. The 24.3 MP sensor, 79-point AF, 12 fps burst, and weather-sealed body remain competitive for stills. Limitations include the absence of 4K video (1080/60p max), the fixed SLT mirror reducing effective sensor exposure by approximately 1/3 stop, and the discontinued A-mount ecosystem. Used bodies with under 50,000 actuations offer substantial remaining shutter life at very attractive prices.
Slightly. The semi-transparent SLT mirror transmits approximately 70% of incoming light to the sensor and diverts 30% to the AF module, effectively reducing sensor exposure by about 1/3 stop. In practice, this is barely noticeable at base ISO but can be a marginal disadvantage at very high ISO settings compared to a mirrorless camera with identical sensor hardware.
The hardware shutter counter cannot be reset by user software. Only Sony authorised service centres can reset the counter. Always verify from an original ARW file rather than a JPEG or screenshot when assessing a used A77 II.