SVBONY SV905C 1.25″ Colour Guide Camera (USB-C, ST4)

Product Overview

The SVBONY SV905C is a compact colour guide camera in a 1.25″ barrel format. It records 1280 x 960 (1.2 MP) with 3.75 µm pixels on a 1/3″-class sensor (4.8 x 3.6 mm image area, 6 mm diagonal), with 4.0 e⁻ read noise, a 13 ke⁻ full well and 12-bit ADC. It connects by USB 2.0 Type-C, carries an ST4 guide port, draws under 0.5 W and weighs 60 g, according to SVBONY.

Who It's For

This is a good match if you need a light, inexpensive guide camera for a guide scope or off-axis guider, with direct ST4 corrections or ASCOM pulse guiding through PHD2. The 3.75 µm pixels suit short guide scopes, and the 1.25″ body slides into a standard guide-scope focuser or OAG.

Key Features & Design

• High-sensitivity guiding sensor: 3.75 µm pixels and low read noise for picking up faint guide stars.
• USB 2.0 Type-C and ST4: one cable for data and an ST4 port for the mount's autoguider input.
• 1.25″ barrel, 36 mm diameter: fits 1.25″ focusers, guide scopes and OAGs.
• CS front interface with a CS-to-C adapter ring for C-mount lenses.
• Snap ring and scale mark: lets you return the camera to the same focus position in a guide lens.
• M28.5 x 0.6 female filter thread and AR-coated protective window.

Camera Design

Guiding needs a camera that can see faint stars in one- to few-second exposures and report their position accurately. The SV905C's 3.75 µm pixels collect more light per pixel than small-pixel planetary sensors, and HCG mode lowers read noise. Exposures run from 64 µs to 20 s, with ROI and 2 x 2 binning, at up to 39 fps.

Recommended Uses

• Autoguiding with a guide scope such as the SVBONY SV106 or SV165.
• Off-axis guiding through a 1.25″ OAG port.
• Planetary capture: SVBONY also lists planetary imaging, with AVI video output.

Compatibility and Accessory Notes

• Software: SharpCap, FireCapture, PHD2 and ASCOM on Windows; AstroDMx Capture on Linux, Raspberry Pi and macOS; SVBONY also lists MDL, N.I.N.A. and TheSkyX.
• Operating systems: Windows 7 and Windows 10, mainstream Linux, Raspberry Pi and macOS.
• Back focus: SVBONY publishes 8.5 mm / 12.5 mm.
• Driver interface: DirectShow.

Good to Know Before You Order

• USB 2.0: ample for guide frames; planetary frame rates top out at 39 fps.
• Computer required: guiding runs from PHD2 or similar software.
• Imaging only: no application in visual observing.
• Published figures: SVBONY lists peak QE as 80% in the specifications and 75% in its description.

Frequently Asked Questions

Is it difficult to set up?

No. Slide the camera into your guide scope or OAG, connect the Type-C cable to your computer and the ST4 cable to the mount (or use ASCOM pulse guiding), then calibrate in PHD2.

Which guide scopes does it fit?

Any guide scope or OAG with a 1.25″ eyepiece holder. SVBONY pairs it with its SV106 guide scope as a kit.

Can I use a C-mount lens?

Yes. The front is CS-mount, and a CS-to-C adapter ring is provided for C-mount lenses.

Bottom Line

In short: a 60 g, 1.25″ colour guide camera with 3.75 µm pixels, ST4 and USB-C, built to slip into a guide scope or off-axis guider and run with PHD2.