Spectrum Optical DS 10" f/5 Dobsonian Reflector Telescope

The Light Bucket That Opens the Deep Sky—Without Breaking Your Back

The Spectrum Optical DS 10 Dobsonian is for observers ready to step into serious aperture territory. With a 10-inch (254mm) parabolic mirror, this telescope brings the cosmos to life in bold, high-contrast detail—offering a viewing experience that rivals what many consider “big league” astronomy, all in a package that remains manageable for one person to transport, set up, and enjoy.

This is a telescope that doesn’t just show you the sky—it immerses you in it. Compared to an 8" model, the DS 10 gathers 160% more light, offering a substantial visual upgrade that becomes obvious the first time you turn it toward a galaxy cluster or rich star field. Dim planetary nebulae, subtle spiral structure in galaxies, the delicate lanes of the Veil Nebula—this is where they start to shine.

Deep Aperture, Fine Optics

At the heart of the DS 10 is a 254mm f/5 parabolic primary mirror, precision-aligned and coated with enhanced aluminum for 93% reflectivity. The fast f/5 focal ratio gives this telescope a wide field of view, perfect for sweeping nebulae and scanning rich Milky Way star clouds, while still delivering enough focal length for high-power planetary work when conditions permit.

Unlike mass-market 10" scopes with spherical mirrors, the DS 10 uses a true parabolic mirror, maintaining sharp focus across the entire field and minimizing off-axis aberrations.

Built for Smooth, Intuitive Motion

Big aperture doesn’t have to mean bulky or awkward. Spectrum Optical has done an impressive job keeping the mechanics elegant and user-friendly:

• Curved spider vanes hold the secondary mirror without introducing the diffraction spikes common to straight-vane designs, delivering cleaner star images and less scattered light around bright objects.

• Altitude tension knobs make it easy to balance the telescope when switching between lightweight eyepieces and heavier 2" glass, without tools or counterweights.

• Teflon azimuth bearings on the rocker box ensure smooth, low-resistance motion across the sky, perfect for star hopping or panning through the Milky Way.

Precision Focus, Even at High Magnification

At f/5, focus is critical—and the DS 10 delivers with a 2" dual-speed Crayford-style focuser. The 10:1 microfocus knob allows for ultra-fine adjustments, essential when observing subtle planetary detail or trying to get pinpoint stars across a wide field. The included 1.25" adapter gives you full compatibility with any modern eyepiece.

What’s in the Box:

• 10" f/5 optical tube assembly (OTA)

• Dobsonian rocker base with Teflon pads and tension-controlled altitude bearings

• Two 1.25" Plössl eyepieces: 23mm and 10mm

• 1.25" Barlow lens to double your eyepiece magnifications

• 8x50 straight-through optical finder scope with mounting bracket

• 2" to 1.25" eyepiece adapter

• Assembly tools

• Printed owner’s manual

Technical Specifications:

• Optical Design: Newtonian reflector on Dobsonian mount

• Aperture: 254mm (10")

• Focal Length: 1250mm

• Focal Ratio: f/5

• Primary Mirror: Parabolic, enhanced aluminum coating (93% reflectivity)

• Focuser: 2" Crayford-style with 10:1 microfocus and 1.25" adapter

• Mount Type: Alt-azimuth Dobsonian with adjustable altitude bearings and Teflon azimuth pads

• Finder Scope: 8x50 optical finder (straight-through)

• Included Eyepieces: 23mm and 10mm Plössl (1.25")

• Additional Accessories: 2x Barlow lens, finder bracket, adapter, tools, manual

• Part Number: DS10

Observing Tip:

The DS 10 is ideal for dark-sky observing, where its generous aperture can truly shine. Use a narrowband or OIII filter with a wide-field 2" eyepiece to unlock the full detail of faint nebulae like the Helix, the Crescent, or the California Nebula. Then shift to the 10mm Plössl and Barlow to split double stars or study fine planetary features like Saturn’s Encke gap or the bands on Mars.

For best results, collimate carefully with a laser or Cheshire tool before each session—especially at f/5—and your views will reward the effort.