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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
Explore Scientific FirstLight 90mm Doublet Refractor with AZ Mount - Discontinued
Explore Scientific FirstLight 90mm Doublet Refractor with AZ Mount - Discontinued
Explore Scientific FirstLight 90mm Doublet Refractor with AZ Mount - Discontinued

Explore Scientific FirstLight 90mm Doublet Refractor with AZ Mount - Discontinued

by Explore Scientific
SKU ES-FL-AR90500AZ
Sold out
$89.99 - $89.99
$89.99
$89.99 - $89.99
$89.99
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  • 90mm Achromatic Doublet Refractor
  • 500mm Focal Length (f/5.5)
  • Manual Alt-Azimuth Yoke Mount
  • Includes 9mm & 20mm Kellner Eyepieces
  • Smartphone Camera Adapter Included
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • Explore Scientific FirstLight 90mm Doublet Refractor with AZ Mount

    The Explore Scientific FirstLight 90mm Doublet Refractor combines a 90mm aperture with a 500mm focal length for impressively wide fields of view. This fast f/5.5 optical system is packaged with 9mm and 20mm eyepieces, a stable alt-azimuth mount, and a smartphone adapter, creating a complete system for observing the Moon, planets, and bright deep-sky objects.

    The 90mm f/5.5 Air-Spaced Doublet Lens

    At the heart of this telescope is a 90mm air-spaced achromatic doublet objective lens. The fully multi-coated optics maximize light transmission for bright, contrast-rich images of everything from lunar craters to star clusters. The fast f/5.5 focal ratio creates a vast field of view, perfect for scanning the Milky Way or framing large objects like the Andromeda Galaxy (M31) or the Orion Nebula (M42).

    While this design delivers excellent wide-field views, the trade-off for a fast achromat is minor chromatic aberration (false color) on the brightest targets like Jupiter or Venus. This is a normal characteristic of this optical design and is well-controlled for its intended use.

    Alt-Azimuth Yoke Mount: Simple, Intuitive Sky Tracking

    Designed for simplicity, the FirstLight 90mm includes a manual alt-azimuth yoke mount. This grab-and-go setup allows you to point the telescope up, down, left, and right, making it easy for anyone to begin navigating the night sky. A slow-motion altitude control rod enables fine adjustments, which is critical for smoothly tracking planets as they drift across the field of view at higher magnifications.

    The mount is supported by a full-size aluminum tripod that provides a stable foundation, minimizing vibrations for steadier views. An integrated accessory tray keeps your eyepieces and other items organized and within reach during observing sessions.

    A Complete Kit with Two Eyepieces and Smartphone Adapter

    This package includes everything you need for your first night out. You get two Kellner eyepieces, a 20mm for low-power, wide-field observation and a 9mm for higher-magnification views of planets and the Moon. The included red dot finder helps you aim the telescope, and an erect-image diagonal provides correctly oriented views, making the scope equally useful for daytime terrestrial observation.

    For those looking to capture their discoveries, the included smartphone adapter allows you to secure your phone to the eyepiece. This setup makes it easy to take your first images of the lunar surface or bright planets, sharing the view with friends and family.

    FirstLight 90mm vs. a 70mm Refractor: The Aperture Advantage

    Many beginner telescopes feature a 70mm aperture, which provides a great introduction to the sky. However, the FirstLight's 90mm objective lens represents a significant step up in light-gathering ability. This increase in aperture directly translates to brighter images and better resolution.

    • Brighter Deep-Sky Views: The extra light grasp of the 90mm lens makes faint objects like the Orion Nebula (M42) appear more vibrant and extended.
    • Higher Resolution: You'll be able to resolve more detail, such as splitting tighter double stars or seeing more distinct cloud bands on Jupiter.
    • Greater Magnification Potential: The larger aperture can support higher useful magnification, allowing you to push the power on nights of steady seeing for closer looks at planetary detail.

  • What can I realistically see with the Explore Scientific FirstLight 90mm refractor?

    The FirstLight 90mm is a capable instrument for a wide range of celestial objects. You can expect detailed views of the Moon's craters and mountains, the rings of Saturn, the primary cloud belts of Jupiter and its four Galilean moons, and the phases of Venus. It will also show you dozens of bright star clusters like the Pleiades (M45), nebulae like the Orion Nebula (M42), and the Andromeda Galaxy (M31) from a dark sky location.

    Is the FirstLight 90mm telescope difficult for a beginner to set up and use?

    No, this telescope is designed for beginners. The alt-azimuth mount is intuitive—simply move it up, down, left, and right to point at your target. Assembly is straightforward and typically takes less than 20 minutes. The included red dot finder makes aiming the telescope much easier than a traditional finderscope.

    How does the FirstLight 90mm perform on Jupiter with the 9mm eyepiece?

    Using the 9mm eyepiece, you will achieve about 56x magnification. This is enough to clearly see Jupiter as a distinct disk, resolve its two main equatorial belts, and track the four bright Galilean moons as they orbit the planet. On nights with steady air, the view will be sharp and detailed.

    Can I use the FirstLight 90mm for daytime viewing of birds or landscapes?

    Yes. The telescope comes with an erect-image diagonal, which corrects the view to be right-side-up and left-to-right correct. This makes it an excellent scope for long-distance terrestrial viewing, such as birdwatching, whale watching from a coast, or enjoying scenic landscapes.

    What is the main benefit of the f/5.5 focal ratio on the FirstLight 90mm?

    The primary benefit of a "fast" f/5.5 focal ratio is a wide true field of view. This makes it easier to find objects and allows you to see large star clusters or nebulae in their entirety within a single view. This is a significant advantage over longer focal ratio telescopes, which have a more "zoomed-in" perspective.

    Can I take pictures of the Moon with the included smartphone adapter on the FirstLight 90mm?

    Absolutely. The Moon is the best target to start with. The smartphone adapter holds your phone's camera steady over the eyepiece, allowing you to take surprisingly detailed and sharp photos of lunar craters and seas, especially when using the lower-power 20mm eyepiece.

  • GTIN 8122570183906
  • Explore Scientific Warranty