A reliable, open-source camera driver for the SIGMA fp L and fp, built for unattended astrophotography with NINA, SharpCap and any ASCOM Alpaca client. Stock colour and mono-converted bodies are supported.
Download the latest release · Installation guide · Source code
Why this driver
The earlier community driver for the fp L worked, but froze whenever the camera’s USB connection reset during an exposure: NINA waited forever, and only restarting NINA and power-cycling the camera helped. This driver was written from scratch to survive whole nights unattended.
| Never hangs | one camera thread, a timeout on every USB transfer, a watchdog |
| Self-healing | a lost USB connection is reported within seconds and re-established automatically; the sequence continues |
| Fast | 10 s frame delivered about 16 s after start; a 61 MP image reaches NINA in about 0.15 s |
| Exact data | DNG decoded in-process, bit-for-bit identical to LibRaw, no processing |
| Mono and colour | bodies recognised by serial number; mono-converted bodies are never debayered |
| Exposures | 1/8000-30 s and 300 s under USB control; any length 1-300 s in Mass Storage mode (Yepkit YKUSH XS + USB relay, together < 100 EUR) |
| Standards | ASCOM Alpaca ICameraV4; passes ASCOM ConformU with no errors, warnings or issues (USB control mode) |
| Hands-off | runs as a Windows service: starts with Windows, restarts itself |
Guides
- Installation: camera settings, USB 2.0, the libusb-win32 driver with Zadig, installing the service.
- Using with NINA and SharpCap: gain/ISO, exposure lengths, mono/colour, what happens on errors.
- Mass Storage mode: 60 s, 120 s, 180 s or any length up to 300 s with a Yepkit YKUSH XS and an LCUS-1 relay.
- DngToTiff: DNG to 16-bit TIFF without interpolation, with flat-field correction, for mono-converted cameras.
- Troubleshooting: common problems and their fixes.
- Developer notes and protocol notes.
Quick start
- Camera: USB mode = Camera Control; plug it into a USB 2.0 port with a good cable of 4 m or less, and clamp the cable at the camera: the USB-C socket does not hold the plug firmly, and any movement drops the connection.
- Zadig: install libusb-win32 for the camera (
1003:C442fp L,1003:C432fp). - Run
Install-SigmaFpAlpaca.ps1from the release in Terminal (Admin). - NINA: Equipment > Camera > refresh > choose the camera > Connect.
- Mono-converted body? Set it to Monochrome on the setup page (http://127.0.0.1:11111/setup).
- Need 60, 120 or 180 s? Set up Mass Storage mode. It needs both a Yepkit YKUSH XS (with its free
ykushcmd.exetool) and an LCUS-1 relay (together < 100 EUR); without them only USB control (up to 30 s and 300 s) is available.
Tested with
| Camera | | |—|—| | SIGMA fp L (mono-converted) | NINA sequences (all night, 274 frames without a failure), USB pull, power-cycle and cable-swap recovery; ConformU | | SIGMA fp L (colour) | Mass Storage mode in NINA: autofocus with 5 s frames, 16 x 120 s in a row | | SIGMA fp (colour) | connection, frames, raw size 6064 x 4042 | | SIGMA fp (mono-converted) | DngToTiff | | Clients | NINA 3.2, SharpCap 4.1, ASCOM ConformU 4.5 |
© 2026 Mark Ford · MIT licence · Developed with Claude Code (Anthropic)
Not affiliated with SIGMA Corporation. “SIGMA”, “fp” and “fp L” are trademarks of SIGMA Corporation.