The original post on this site was a product description of the Celestron ExploraScope 114AZ (model 22103). This rewrite uses Celestron’s current product page for verified specifications and explains one figure that beginners should treat with caution.
Verified specifications
From Celestron’s ExploraScope 114AZ product page:
- Optical design: Newtonian reflector
- Aperture: 114 mm
- Focal length: 1000 mm; focal ratio f/9
- Eyepieces: 20 mm (50x) and 4 mm (250x)
- Barlow lens: 3x (1.25-inch)
- Finder: StarPointer red dot finderscope
- Highest useful magnification: 269x
- Lowest useful magnification: 16x
- Limiting stellar magnitude: 12.8
- Light-gathering power: 265 times the unaided eye
- Optical tube length: 24 inches
- Mount: manual alt-azimuth, with a slow-motion rod control
- Tripod: aluminium, 52 inches maximum height, with accessory tray
- Total kit weight: 6.7 lb
- Software: Celestron Starry Night Basic Edition and the SkyPortal app
Understanding the “750x” claim
Celestron’s page says that, combined with the 3x Barlow lens, the telescope provides up to 150x with the 20 mm eyepiece or 750x with the 4 mm eyepiece. The arithmetic is correct: 250x × 3 = 750x. But the same page lists the highest useful magnification as 269x. Above that, the image gets larger but dimmer and blurrier, without showing more detail.
Orion’s AstroView manual explains why: every telescope has a useful limit of about 2x per millimetre of aperture, and higher claims are a misleading gimmick. For 114 mm that is about 228x, close to Celestron’s 269x. In practice, the 20 mm eyepiece alone (50x) and with the Barlow (150x) are the useful combinations. The 4 mm eyepiece (250x) is already near the limit and needs very steady air.
Magnification made simple
Magnification equals the telescope’s focal length divided by the eyepiece’s focal length:
- 20 mm eyepiece: 1000 ÷ 20 = 50x
- 4 mm eyepiece: 1000 ÷ 4 = 250x
- A Barlow lens multiplies these by its factor, here 3x.
Always start with the lowest power to find objects, then increase it. Orion’s manual explains that at higher powers an image is always dimmer and less sharp, and that a small but well-resolved image shows more detail than a dim, fuzzy, over-magnified one.
What the other numbers mean
- Light-gathering power, 265x: Celestron says the 114 mm mirror collects 265 times as much light as your unaided eye, which is why faint clusters and nebulae become visible.
- Limiting magnitude, 12.8: the faintest stars the telescope can show under good skies. Orion’s manual says a sky is transparent enough for faint objects when you can see stars of 6th magnitude or fainter with the unaided eye, so the telescope reaches far fainter stars than your eyes alone.
- Resolution, 1.02 arc seconds (Dawes): a measure of how close two stars can be and still be seen as two. Smaller numbers are better.
The mount and finder
The manual alt-azimuth mount moves up and down and left and right, which is intuitive for beginners. Celestron includes a slow-motion rod for smooth, accurate pointing. The StarPointer red dot finder projects a dot onto the sky to help you aim the telescope.
What can you see?
Celestron describes the ExploraScope 114AZ as designed for the beginner to discover the Moon, the rings of Saturn, the moons of Jupiter and the Orion Nebula. Orion’s manual for a similar-size beginner telescope adds realistic expectations:
- The Moon: best during partial phases, when shadows show craters clearly
- Jupiter: cloud bands and the four largest moons
- Saturn: the rings, and often the moon Titan
- The Orion Nebula and other deep-sky objects: soft grey glows rather than the colours seen in photographs
Beginner tips
Orion’s refractor manual gives general advice that applies to any telescope:
- Cool the telescope for at least half an hour outdoors.
- Dark-adapt for about 30 minutes and use a red light.
- Avoid heat sources such as rooftops and asphalt.
- Watch the seeing: if stars twinkle strongly, stay at low power.
Light weight, easy setup
At 6.7 lb for the whole kit, the ExploraScope 114AZ is easy to carry outside. Celestron says it offers quick, no-tool setup. That makes it more likely to be used often, which matters more than magnification.
Safety
Never look at the Sun through the telescope or its finder without a professionally made solar filter that completely covers the front of the telescope.
Quick summary
- 114 mm, 1000 mm, f/9 Newtonian reflector on a manual alt-az mount; 6.7 lb kit.
- 20 mm (50x) and 4 mm (250x) eyepieces plus a 3x Barlow.
- Highest useful magnification is 269x, so ignore the “750x” headline.
- Good for the Moon, Jupiter, Saturn and the Orion Nebula.
Jargon buster
- Barlow lens: an accessory that multiplies an eyepiece’s magnification.
- Highest useful magnification: the most power that still shows extra detail.
- Limiting magnitude: the faintest stars the telescope can show.
- Alt-azimuth mount: a mount that moves up-down and left-right.
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