Explore Scientific AR102 f/6.5 Air-Spaced Doublet OTA

Like its two larger brothers, the AR127, and the AR152, these are classic air-spaced, crown-and-flint, doublet achromatic refractors with superior-class optical figure, in a short (f/6.5) focal length design. These optics are an extreme value, produce stunning images of deep sky objects, double stars, planets, and the moon that are a small fraction of the price of comparable aperture apochromat refractors. Finally one can own a diffraction-limited high quality refractor for a relatively modest investment.

Designed to handle the rigors of public star parties and educational outreach, the Explore Scientific AR Series has standard hardware which includes a precision two-speed focuser, a 99% reflective 2-inch diagonal mirror, and an 8x50 finder scope. You can be confident that the quality and construction of these telescopes will allow heavy use for many years. The optics in their collimatable lens cell are fully multi-coated to eliminate light scatter and maintain image contrast. We precision collimate every Explore Scientific telescope at our factory to give optimum performance. Although you may never need to adjust optical alignment, the AR Series allows for collimating the lens set should the telescope ever require it. Deluxe two-speed focuser the Explore Scientific Air-Spaced Doublet AR Series telescopes include a precision 2-inch two-speed as standard equipment. The eyepiece holder uses a compression ring to prevent the eyepiece or camera barrel from scoring. Perfect focus is easily achieved with the Explore Scientific ten-to-one, two-speed focuser on those prestine nights of steady seeing, Saturn’s rings can forever affect the hearts and minds of almost anyone who lays eyes on them. It’s nights like these that astronomers like to set up their refractors and push the magnification to the limits, not only to see the magnificence of the planet at greater scale but to really test the optical and mechanical quality of the telescope. Many telescopes are only supplied with a standard single-speed focuser, you will find that a tiny nudge will throw out focus and turn your night into one of frustration. So we included as standard equipment, on all Explore Scientific AR Series, a two-speed Crayford-style precision focuser with tension adjustment and lock to obtain and hold perfect focus. We think you’ll agree that such precision is worth it.

Features:

• Optical design: air-spaced doublet achromatic refractor
• Clear aperture: 102mm
• Focal length: 663mm
• Focal ratio: f/6.5
• Resolving power: 1.14 arc seconds
• Coatings: fully multi-coated
• Limiting stellar magnitude: 12.5
• Focuser: two-speed Crayford-style, w/adjustable tension and lock
• Finder Scope: 8x50 straight; adjustable objective focus; dual-ring, six-point, bracket w/quick release shoe
• Cradle/saddle plate: dual ring style – fits Explore Scientific mounts; and other third party mounts that accept Vixen-type rail
• Tube diameter: 3.96” – 100.7mm
• Dew-sield diameter: 7.5” – 100.7mm
• Tube length 25.5” – 648mm
• Tube construction: aluminum; stainless steel

The kit includes:

• Optical tube with removable dew-shield
• Front and rear dust covers
• Cradle rings with handle and univsersal saddle plate
• Two-speed focuser 2.0” I.D.
• 8x50 finderscope with six point adjustable racket
• 2.0” 99% reflective mirror diagonal with 1.25” adapter