# Sony A7S III and A7 IV shutter angle hack: what works and what it risks

> A7S III owners are adding shutter angle, Variable Shutter and BIG6 via Sony's USB service mode. What works, what survives a reboot, and the warranty risk.

- URL: https://www.4filmmakers.co/news/sony-a7s-iii-a7-iv-shutter-angle-hack/
- Publisher: 4FILMMAKERS (https://www.4filmmakers.co/)
- Topic: Cameras & drones (https://www.4filmmakers.co/topics/cameras/), Software (https://www.4filmmakers.co/topics/software/)
- Published: 2026-11-05
- Updated: 2026-11-05
- Keywords: Sony A7S III shutter angle, A7S III shutter angle hack, Sony A7 IV shutter angle, A7S III Variable Shutter, Sony BIG6 home screen, Sony service mode hack, Sony cameras with shutter angle

Since mid-October, owners of the Sony A7 IV and A7S III have been switching on video features that Sony keeps for its Cinema Line bodies. They use the camera's USB service mode and an open GitHub research project, with no new firmware flashed. On 22 October a reader told SonyAlphaRumors that one changed setting gave an A7S III on firmware 5.01 a shutter angle display. On 3 November a Reddit user showed Variable Shutter and the BIG6 home screen running on the same camera. Sony hasn't commented, and its European guarantee excludes "upgrading the product beyond specifications or features described in the instruction manual".

Nothing here is an official update. Sony's current firmware is 6.02 for the A7 IV and 5.01 for the A7S III, both released on 28 May 2026, and neither adds these menus. If you want shutter angle or BIG6 with support behind it, you still need an FX3, FX30, FX2 or FX5.

## In short

- A7S III, firmware 5.01: one reader enabled shutter angle by changing a single stored setting in service mode. It survives a reboot and you can write the old value back.
- A7S III: a Reddit user patched Variable Shutter and BIG6 into memory over USB. Those patches vanish on reboot, though the user says one write to the settings memory makes Variable Shutter stick.
- A7 IV, firmware 6.02: the GitHub project behind the work lists the shutter angle display as verified, but says you still can't adjust the angle.
- Cine EI, base ISO selection and open gate stay locked. The reader who tested the A7S III found them tied to the FX3's product class in firmware.
- Risk: the first A7 IV hacker warned about bricking, and Digital Camera World reported a boot loop after an 8K attempt. Sony's warranties in Europe and the US both exclude unauthorised modifications.

## What have owners switched on so far?

Three separate reports, on two cameras that share the same CXD90057 processor platform. They don't all use the same method, and the results differ more than the headlines suggest.

Table: Reported hacks on the A7 IV and A7S III, October to November 2026

| Date | Camera | Feature | Method | After a reboot | Status |
|---|---|---|---|---|---|
| 15 Oct | A7 IV | Shutter angle | Firmware decrypted through a path traversal bug; enabling steps not published | Not stated | Reddit post; the bug details stayed private |
| Ongoing | A7 IV, fw 6.02 | Shutter angle, custom LUT, open gate, de-squeeze | Service mode, stored settings only | Stored settings persist | Angle display verified, adjustment "still gated"; LUT gate unresolved; open gate unproven; de-squeeze untested |
| 22 Oct | A7S III, fw 5.01 | Shutter angle | Service mode, one stored setting from 00 to 01 | Persists; write 00 to undo | Shown in Movie mode after a cold restart, per one reader |
| 3 Nov | A7S III | Variable Shutter, BIG6 | Code run over a hidden USB update channel, menus patched in RAM | RAM patches are lost; one write to settings memory keeps Variable Shutter | Screenshots from one Reddit user |

The A7 IV row and the A7S III rows don't agree on one point. The GitHub README says the A7 IV shows the angle setting but routes the dial away from it, so you can't change the value. The A7S III reader describes the mode switching on with a default of 180 degrees and doesn't mention that limit. Until someone posts footage shot at several angles, treat adjustable shutter angle on either body as unconfirmed.

## How does it work without new firmware?

Sony cameras keep their settings in a backup memory that survives power cycles. The GitHub project, by leogenot and released under the MIT licence, maps which stored values switch which menus, and changes them through the USB service mode that the open-source Sony-PMCA-RE tool can reach. The reader on the A7S III took a full backup of the settings first, changed one value, pulled the battery for ten seconds, and found the shutter angle option in Movie mode.

The 3 November report goes further. The Reddit user describes a hidden update channel, called Jiritsu in the firmware, that stays open over USB even in plain Mass Storage mode and lets their own code run with full system access. With that, they patched the per-model menu tables in memory so the greyed-out Variable Shutter and BIG6 entries appear. A restart wipes those patches. The user then says a single write to the settings memory makes Variable Shutter permanent, and our sources don't show anyone else repeating it yet.

We're not publishing the steps. The GitHub README opens with "Use this at your own risk, I am not responsible for any damages", and on a camera you earn money with, that line deserves a second read.

## Which Sony cameras have these features officially?

We checked each camera's help guide. Variable Shutter here means Sony's fine shutter adjustment against flicker in movie mode; BIG6 is the six-box home screen with frame rate, ISO, shutter, iris, look and white balance.

Table: Official support, from Sony's help guides (checked 5 November 2026)

| Camera | Shutter angle | Variable Shutter in movies | BIG6 home screen |
|---|---|---|---|
| FX3 | Yes, from firmware 6.00 | Not listed | Yes, from firmware 7.00 |
| FX3A | Yes | Not listed | Yes |
| FX30 | Yes, from firmware 5.00 | Yes | Yes, from firmware 6.00 |
| FX2 | Yes | Yes | Yes |
| FX5 | Yes, Step and Continuous modes | No separate entry; Continuous sets any speed or angle | Yes |
| A7 IV | No | Yes | No |
| A7S III | No | No (stills anti-flicker only) | No |
| A7 V, A1 II, A7C II, A9 III, ZV-E1, A6700 | No | Yes | No |

The A7 IV already has Variable Shutter, so the hack only adds shutter angle there. The A7S III, Sony's video-first Alpha, is the one body in this list with neither feature, and that's why its owners care. Sony shipped shutter angle to the FX3 in 2024 and BIG6 in August 2025; the A7S III shares the FX3's sensor and has had no feature update of that kind.

## Is it worth the risk for your shoots?

Shutter angle is another way to express exposure time, and the image comes out the same. At 25p, 180 degrees is 1/50 s, and you can dial 1/50 on any A7S III today. The angle earns its place when you switch frame rates often, because it keeps the motion blur constant without you doing the maths, and when your crew talks in degrees.

Variable Shutter is the more useful one. In Europe, mains lighting runs at 50 Hz, so at 25p or 50p a shutter of 1/50 or 1/100 keeps most practical lights clean. LED walls, monitors in shot and cheap LED panels don't follow those numbers, and fine shutter steps are how you get rid of their banding. That's the feature an A7S III owner shooting events or interviews would miss most.

Table: Our take by situation

| You are | Our advice | Why |
|---|---|---|
| Paid shooter with one A7S III | Leave it alone | A bricked body costs you the job; Sony can refuse warranty repairs |
| Owner of a spare, out-of-warranty A7S III | Wait for more reports | Only one person has shown each result so far |
| A7 IV owner who wants shutter angle | Not yet | The project says the angle can't be adjusted on 6.02 |
| Fighting LED flicker on an A7S III | Shoot tests at fixed speeds first, or rent an FX3/FX30 for the job | Variable Shutter on the A7S III comes from one Reddit report |
| Buying a body for these menus | FX30, FX3 or FX2 | Shutter angle and BIG6 come with support and updates |

## What happens to your warranty?

Sony's European guarantee, the document Sony Europe publishes for its consumer products, excludes "adjustments or adaptations without Sony's prior written consent", including "upgrading the product beyond specifications or features described in the instruction manual". Shutter angle on an A7S III isn't in its manual. The US limited warranty for Sony's interchangeable-lens cameras goes further and excludes "rooting or other modifications to control the behavior of the product or any factory installed operating system".

Sony's European text also says it doesn't affect your statutory rights against the shop that sold you the camera. In the EU that legal guarantee lasts at least two years from delivery. If a fault turns up after you've been in service mode, expect the seller and Sony to ask what you changed. Writing the original value back undoes the A7S III shutter angle setting, according to the reader who tried it, but nobody has published what a Sony service centre can or can't see afterwards.

Table: Pros and cons of the service-mode route

| Pros | Cons |
|---|---|
| No firmware flash; the stored-setting change can be reversed | Sony's guarantee excludes features beyond the manual |
| Free, open-source research you can read before deciding | One report per result, no footage tests at different angles |
| Variable Shutter would fix a real gap on the A7S III | The deeper method runs your own code on the camera, where a mistake can brick it |
| Doesn't touch image processing or codecs | A future Sony firmware could reset or block the change |

If you're on the A7S III and want to stay inside Sony's support, our [Sony timecode guide](https://www.4filmmakers.co/news/sony-timecode-dji-mic-3-rode-wireless-pro/) covers what the camera can lock to today, and our [Monitor & Control guide](https://www.4filmmakers.co/news/sony-monitor-control-a6700-zv-e10-ii/) explains Sony's official app route for extra monitoring tools. For the newest Cinema Line body with every one of these menus, see our [FX5 shipping update](https://www.4filmmakers.co/news/sony-fx5-shipping-date/).

## Questions people ask

**Q: Does the Sony A7S III have shutter angle?**
Not officially. Sony's help guide for the A7S III lists no shutter angle mode, and firmware 5.01 doesn't add it. One owner enabled it through service mode in October 2026, which Sony doesn't support.

**Q: Is the A7S III shutter angle hack permanent?**
The reader who did it changed one stored setting, which survives a reboot. Writing the original value back undoes it. The separate Variable Shutter and BIG6 patches live in memory and disappear on restart, unless you also write to the settings memory.

**Q: Does the hack void the Sony warranty?**
Sony's European guarantee excludes adaptations made without its consent, including upgrades beyond the features in the manual. The US warranty excludes rooting and modifications to the camera's operating system. Your statutory rights against the seller still apply.

**Q: Can the A7S III get Cine EI or open gate this way?**
No. The A7S III tester found Cine EI, base ISO selection and the Cinema Line menu tied to the FX3's product class, and found no open gate readout mode for the A7S III sensor in the firmware.

**Q: Which Sony cameras have shutter angle officially?**
The FX3 (from firmware 6.00), FX3A, FX30 (from firmware 5.00), FX2 and FX5. No Alpha body in Sony's current help guides has it, including the A7 V and A1 II.

## Sources

- SonyAlphaRumors: [A7 IV shutter angle (15 Oct 2026)](https://www.sonyalpharumors.com/curiosity-guy-on-reddit-enabled-shutter-angle-on-the-a7iv-by-doing-some-reverse-engineering/), [A7S III shutter angle (22 Oct 2026)](https://www.sonyalpharumors.com/new-shutter-angle-hack-works-on-the-sony-a7siii-too/), [Variable Shutter and BIG6 on the A7S III (3 Nov 2026)](https://www.sonyalpharumors.com/the-hacking-continues-variable-shutter-and-big6-added-on-the-sony-a7s-iii/)
- GitHub, [leogenot/sony-a7iv-feature-research](https://github.com/leogenot/sony-a7iv-feature-research) (README and research status table, read 5 Nov 2026)
- Digital Camera World, [Videographer hacks Sony A7 IV](https://www.digitalcameraworld.com/cameras/mirrorless-cameras/videographer-hacks-sony-a7-iv-to-add-this-feature-i-found-a-path-traversal-bug-allowing-me-to-get-the-fully-decrypted-firmware) (19 Oct 2026); DIYPhotography, [Hackers unlock hidden Sony A7S III Variable Shutter feature](https://www.diyphotography.net/hackers-unlock-hidden-sony-a7s-iii-variable-shutter-feature/) (4 Nov 2026)
- Sony help guides: [FX3 shutter mode](https://helpguide.sony.net/ilc/2210/v1/en/contents/TP1001690662.html) and [home screen](https://helpguide.sony.net/ilc/2210/v1/en/contents/TP1002071061.html), [FX3A](https://helpguide.sony.net/ilc/2510/v1/en/contents/241h_shutter_mode.html), [FX30](https://helpguide.sony.net/ilc/2220/v1/en/contents/TP1001690662.html), [FX2](https://helpguide.sony.net/ilc/2530/v1/en/contents/241h_shutter_mode.html), [FX5](https://helpguide.sony.net/ilc/2630/v1/en/contents/shutter_adj.html), [A7 IV Var. Shutter](https://helpguide.sony.net/ilc/2110/v1/en/contents/TP1000659392.html), [A7S III](https://helpguide.sony.net/ilc/2410/v1/en/index.html), [A7 V](https://helpguide.sony.net/ilc/2540/v1/en/contents/201h_anti_flicker_comparison.html), [A1 II](https://helpguide.sony.net/ilc/2440/v1/en/contents/201h_anti_flicker_comparison.html)
- Firmware dates: Newsshooter, [A7S III and A7 IV firmware updates](https://www.newsshooter.com/2026/05/29/sony-a7s-iii-a7-iv-firmware-updates/); Brian Smith on [FX3 6.00 / FX30 5.00](https://briansmith.com/sony-releases-major-firmware-updates-for-fx3-fx30-cinema-cameras/) and [FX3 7.00 / FX30 6.00](https://briansmith.com/sony-releases-fx3-ver-7-00-fx30-ver-6-00-firmware-updates/)
- Warranty: Sony Europe, [European guarantee terms](https://services.sony.ie/support/files/warranty/pdf/warranty_en_IE.pdf); Sony US limited warranty for interchangeable-lens cameras (document 4-698-500-64, [copy hosted by Abt](https://content.abt.com/documents/176488/sony-camera-ILMEFX2-warranty.pdf))
- Cover: Sony A7S III, image from [Sony UK's product page](https://www.sony.co.uk/interchangeable-lens-cameras/products/ilce-7sm3), graded by 4FILMMAKERS