Explore Scientific FirstLight 254mm f/5 Alt-Az Dobsonian Telescope

BH #EXFL10STD • MFR #FL-DOB1005-01
Explore Scientific
Explore Scientific FirstLight 254mm f/5 Alt-Az Dobsonian Telescope
Key Features
  • Large 254mm Aperture
  • 1270mm Focal Length, f/5 Focal Ratio
  • Low-Expansion Glass Primary Mirror
  • Borosilicate Glass Secondary Mirror
Sporting a distinctive large aperture and deep light bucket, the Explore Scientific FirstLight 254mm f/5 Alt-Az Dobsonian Telescope gives users powerful performance at a reasonable price. Its large parabolic primary and smaller secondary mirrors are made from low-expansion glass to eliminate distortion across the entire field of view, especially at the edges, while allowing sharp resolution of star clusters and nebulae that smaller apertures cannot achieve.
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Expected availability: Oct 06, 2021
$849.99
$71/mo. suggested payments
with 12 Mos. Promo Financing* 
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Explore Scientific FirstLight Overview

  • 1Description
  • 2Optical Tube
  • 3Mount
  • 4Focuser
  • 5Included Accessories

Sporting a distinctive large aperture and deep light bucket, the Explore Scientific FirstLight 254mm f/5 Alt-Az Dobsonian Telescope gives users powerful performance at a reasonable price. Its large parabolic primary and smaller secondary mirrors are made from low-expansion glass to eliminate distortion across the entire field of view, especially at the edges, while allowing sharp resolution of star clusters and nebulae that smaller apertures cannot achieve.

The fast f/5 focal ratio and hexagonal rack-and-pinion focuser make this an ideal choice for imaging, by enabling shorter exposure times with the ability to achieve tack-sharp focusing with the strength to handle large imaging rigs and eyepieces. This 2.5" focuser is designed to eliminate vignetting when using large wide-field eyepieces when observing, and when using large imaging sensors for astrophotography. Reducer adapters are included allowing the use of both 1.25" and larger 2" eyepieces and accessories.

The heavy base provides a rock-steady platform with very low vibrations. This alt-az rocker mount features Teflon pads on the ground plate, and large altitude wheels for smooth and easy movement along both axes with little vibration. Dual mounting rings allow the OTA to be precisely balanced for even smoother movement, and the altitude wheels can be removed and replaced with a Losmandy-style dovetail plate so the OTA can be used with EQ and GoTo mounts mounted on large tripods or piers.

Optical Tube

  • 254mm (10") aperture
  • f/5 focal ratio
  • 1270mm focal length
  • Optical design: Dobsonian-variant of a Newtonian reflector
  • Low-expansion H-PZ33 glass primary mirror
  • 74mm low thermal-expansion Borosilicate glass secondary mirror resists expansion to limit aberrations

Mount

  • Alt-az rocker design
  • Large aluminum altitude wheels allow for smooth movement and tracking with reduced vibration
  • Teflon pads on ground plate enable smooth 360° rotation
  • Adjustable mounting rings enable precision balancing when using lighter or heavier accessories for smoother motion
  • Mounting rings allow the altitude wheels to be removed and replaced with a Losmandy-style dovetail for attachment to an EQ, alt-az, or GoTo mount head for tripod/pier use

Focuser

  • Large 2.5" hexagonal rack-and-pinion design
  • Provides strength and rigidity to handle heavy eyepieces and imaging rigs with little backlash, tilt, or shifting
  • Large drawtube prevents vignetting with wide-field eyepieces during observation, or when using large imaging sensors for astrophotography
  • Includes 2" and 1.25" eyepiece adapters to allow use of a variety of eyepieces and accessories

Included Accessories

    Super Plössl eyepiece:
  • 1.25" diameter barrel
  • 25mm yields 51x power
    Finderscope:
  • Conventional 6x30
  • Wide-field for fast subject acquisition and easy star hopping
UPC: 812257018284

Explore Scientific FirstLight Specs

Optical Tube Assembly
Optical DesignDobsonian Reflector
Aperture254 mm / 10"
Focal Length1270 mm
Focal Ratiof/5
FocuserRack-and-Pinion
Eyepiece Barrel Diameter1.25", 2"
DiagonalNone
FinderscopeYes
MountingLosmandy Style
Optical Tube Dimensions47.2 x 11.8" / 120 x 30 cm
Mount
TypeManual; Alt-Azimuth
General
BatteriesNone
GPSNo
Wi-FiNo
Weight28.7 lb / 13 kg (OTA)
61.5 lb / 27.9 kg (Fully Assembled)
Packaging Info
Package Weight82 lb
Box Dimensions (LxWxH)58 x 20.4 x 19.8"
See any errors on this page? Let us know

YOUR RECENTLY VIEWED ITEMS

Bought a diagonal prism for the unit it does not ...

Bought a diagonal prism for the unit it does not work I can take the inch and 1/4 adapter off and the focuser extension shell off and slide my diagonal prism in it works but I have very little movement with it don't have much of a focal range do yall sell a diagonal prism that comes with the unit that works with the unit
Asked by: Erich
Newtonian style telescopes are not designed to use a diagonal. the mirror in the diagonal will prevent you from getting a focused image.
Answered by: Damon
Date published: 2020-05-05

What material is the tube composed of?

What material is the tube composed of?
Asked by: Jim
The tube is composed of metal. Probably a sheet metal such as steel or aluminum.
Answered by: Dan
Date published: 2020-10-28

Can I attach my Canon 6D or T2i to this?

Can I attach my Canon 6D or T2i to this?
Asked by: Kenneth
Yes you can, you will just need an adapter like the Vello T-Mount Lens to Canon EF/EF-S-Mount Camera Lens Adapter, BH #VELACEFT. https://bhpho.to/2gWc43b
Answered by: Joseph
Date published: 2019-10-03

question

Where is the assembly manual
Asked by: Anonymous
It's on explore scientific webpage for this telescope under the extra tab below the description tab
Answered by: John
Date published: 2020-05-06
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