SVBONY SV535 f/2.8 7-Element 5-Group APO Astro Camera Lens

SVBONY SV535: A 105mm Lens for Astro & Terrestrial Imaging

SVBONY designed the SV535 to optimize image quality for astrophotography while also meeting the needs of terrestrial imaging. Its form factor resembles a traditional camera lens, making it intuitive for photographers transitioning to astronomical targets. However, its internal design and external features are purpose-built for the demands of capturing faint celestial objects.

The 105mm focal length provides an expansive field of view for capturing large-scale structures in the night sky or framing broad landscapes during the day. Its integrated structure removes the need for additional optical accessories, which keeps a portable imaging setup simple.

A 7-Element, 5-Group APO Design at f/2.8

At the core of the SV535 is its apochromatic (APO) optical system. The 7-element, 5-group lens configuration is designed so that edge distortion and chromatic aberration (false color fringing, most noticeable around bright stars in simpler lens designs) are greatly controlled.

The fast f/2.8 focal ratio is a key advantage for astrophotography. It allows your camera's sensor to gather light rapidly, enabling shorter exposure times for faint targets like emission nebulae and galactic dust lanes. The optics are fully multi-coated (FMC) to improve light transmission and reduce internal reflections.

The M42x0.75 Connection: Short Back Focus Explained

The SV535 connects to your camera via a standard male M42x0.75 thread, often referred to as a T-thread. However, its back focus is short: 24mm, measured from the rear thread surface.

Because of this, the SV535 does not support DSLR cameras or the commonly used T-mount camera adapters. For mirrorless cameras, SVBONY offers Sony E-mount, RF mount and Z mount adapters (sold separately if needed); with the Sony E-mount adapter (5.5mm) the camera's own 18.5mm flange distance completes the 24mm. For astronomy cameras, the recommended combination is a 6.5mm M42 extension tube plus an 11mm M42 extension tube plus the camera's own 6.5mm flange distance.

Fine-Tuning Focus with the SV535's Helical Focuser

The SV535 focuses manually with a helical focuser: you rotate the threaded focusing ring. For landscapes, focus comes quickly; for night sky work, turn the ring slowly to fine-tune focus.

Use the screen magnification function most cameras offer: point at a bright star, magnify the live view and turn the focusing ring slowly until the star is at its smallest.

Vixen and Arca-Swiss Plates

The SV535 comes with two mounting plates: a Vixen dovetail plate and an Arca Swiss plate, the two common saddle standards in astronomy and photography.

The standard Arca and Vixen plates connect easily to most equatorial mounts and camera tripods, so no tube rings are needed.

M48 Threading for Standard 2-Inch Filters

The front of the SV535's objective is equipped with a female M48x0.75 thread, a standard interface in astrophotography. This allows you to directly attach standard 2-inch astronomical filters for light pollution suppression or narrowband imaging. The included M48 metal lens cover protects these threads when not in use.

Adding a filter is essential for imaging from urban or suburban skies. A dual-band or multi-bandpass filter increases the contrast of emission nebulae against a bright sky background.

Full-Frame Coverage for Expansive Targets

The SV535 is full-frame compatible. On a full-frame camera, the 105mm focal length gives a field of roughly 19 by 13 degrees, enough for some of the largest objects in the night sky in a single frame.

• Massive Nebulae: Targets like the North America Nebula (NGC 7000) or the Vela Supernova Remnant fit comfortably within the frame.
• Galaxies: Frame the Andromeda Galaxy (M31) with its satellite galaxies M32 and M110.
• Constellation Portraits: The wide field suits imaging entire constellations or prominent asterisms, revealing faint dust clouds and star-forming regions that connect the bright stars.

The Complete SV535 Kit: 8 Included Pieces

The SVBONY SV535 arrives as a complete package, ready for the field. A soft padded case is included for transport and storage.

Inside the case, you will find the SV535 lens itself, along with essential accessories. It includes a Vixen dovetail plate, an Arca Swiss plate, an M42 metal lens cover, an M48 metal lens cover, a wrench and screw, and the instruction manual.

Getting Started with the SV535: A 5-Step Guide

Deploying the SV535 is straightforward, especially if you are familiar with manual camera lenses. Following these steps will help you achieve a successful first night of imaging.

1. Attach Your Camera: Connect your astronomy camera (with the specified M42 extensions) or your mirrorless camera (with an E-mount, RF or Z mount adapter) to the rear M42x0.75 male thread so the 24mm back focus is met.
2. Mount the Lens: Secure the Vixen or Arca Swiss plate into the matching saddle on your equatorial mount, star tracker, or tripod. Ensure it is balanced properly.
3. Frame Your Target: Point the lens toward your desired object in the sky. Use short test exposures to confirm your framing and composition.
4. Achieve Critical Focus: Aim at a bright star near your target. Using your camera's live view, zoom in digitally as far as possible. Slowly rotate the helical focuser until the star is a sharp, tiny point of light. A Bahtinov mask can help achieve accurate focus.
5. Begin Imaging: Once focused, slew back to your target and begin your sequence of light frames. Remember to use the included dew shield to protect the front element from stray light and moisture.