SVBONY SV216 2X 4-Element Barlow Lens - 1.25"
- 2x Magnification Factor
- 4-Element Optical Design
- 1.25 inch Barrel Size
- 3-Screw Coaxial Clamping System
- Fully Multicoated Lenses
The SVBONY SV216 1.25" Barlow Lens doubles your telescope's effective focal length using an advanced 4-element optical design to maintain a flat, sharp field of view. Its coaxial clamp utilizes 3 M3x10 thumbscrews for precise optical alignment, and the barrel's M28.5x0.6 threads accept standard 1.25" filters for enhanced planetary contrast.
Unlike standard 2-element Barlows, the SV216 uses a 4-element lens group to deliver superior optical correction. This design significantly reduces chromatic aberration and flattens the field, ensuring stars remain sharp points even at the edge of wide-angle eyepieces. Fully multicoated surfaces on all elements maximize light transmission for bright, high-contrast views of planetary details like Jupiter's Great Red Spot or the Cassini Division in Saturn's rings.
The SV216 replaces the single-screw standard with a robust 3-screw clamping system. This design allows you to apply even pressure from multiple points, forcing the eyepiece barrel to align perfectly with the Barlow's optical axis. This coaxial alignment is critical for high-magnification imaging and viewing, preventing optical tilt that can soften an entire side of the image. A brass compression ring prevents the stainless steel thumbscrews from marring your eyepiece barrels.
A standard 2-element achromatic Barlow, like a Celestron Omni, is often lighter and more affordable, making it a common entry-level choice. However, the optical and mechanical design of the SVBONY SV216 provides distinct advantages for serious planetary observation and imaging.
The primary advantage of the 4-element design is superior optical correction compared to simpler 2-element Barlows. It produces a flatter field of view, meaning stars stay sharp closer to the edge, and it significantly reduces chromatic aberration (color fringing) on bright objects.
The 3-screw clamp ensures your eyepiece or camera is held perfectly on the optical axis (coaxially). A single thumbscrew can push the eyepiece slightly to one side, creating tilt that degrades sharpness, especially at high magnification. The SV216's design provides even pressure for a more precise, stable optical train.
Yes. The 1.25" barrel is threaded with standard M28.5x0.6 threads, allowing you to attach any standard 1.25" filter. This is ideal for using color filters to enhance planetary features or a UV/IR cut filter for imaging.
Absolutely. An 8" SCT has a focal length around 2000mm. The SVBONY SV216 2x Barlow will double this to 4000mm (f/20), providing the ideal image scale for capturing fine detail in Jupiter's cloud bands with most modern planetary cameras. The flat-field 4-element design will keep the planet sharp across the entire sensor.
Yes, it's an excellent match. Fast telescopes (f/4-f/5) and wide-angle eyepieces are very demanding on optics. The SV216's 4-element design provides the necessary correction to control aberrations like coma and astigmatism at the edge of the field, which would be amplified by a simpler Barlow.
Most likely, yes. The SVBONY SV216 weighs 7.72oz (219g), which is significantly heavier than a standard eyepiece or a lightweight Barlow. You should expect to adjust your counterweights or tube position to maintain proper balance, especially on smaller mounts.
| Brand | SVBONY |
| Magnification Factor | 2x |
| Barrel Size | 1.25 inch |
| Lens Elements | 4 |
| Lens Coatings | Fully multicoated |
| Filter Threads | M28.5x0.6 |
| Compression Ring | Yes |
| Barrel Material | Stainless Steel |
| Barrel Type | Straight Barrel |
| Thumbscrews | 3 |
| Thumbscrew Thread | M3x10 |
| Insertion Depth | 1.55 inch / 39.5 mm |
| Length of Upper Body | 2.34 inch / 59.5 mm |
| Max Diameter | 1.73 inch / 44 mm |
| Net Weight | 7.72 oz / 219 g |