SkyMaster Pro 20x80 vs 15x70 Pro: Which Should I Buy in 2026?

SkyMaster Pro 20x80 vs 15x70 Pro: Which Should I Buy in 2026?

Celestron's SkyMaster Pro line sells both of these as separate products, and the choice is a real trade-off: per Celestron's own pages, the Pro 15x70 is lighter and shows a wider field of view, while the Pro 20x80 gathers more light and reaches higher magnification at the cost of nearly double the weight and a narrower view. One detail matters before either number: the Amazon listing this page links is for Celestron's standard SkyMaster 15x70, a related but different product from the SkyMaster Pro 15x70 named in the question above, so this page also covers the gap between the two 15x70 versions.

Updated October 2026.

We did not test this product ourselves; this review is built from the manufacturer's published specifications and Amazon's product listing.

Two Celestron Lines, Not Just Two Sizes

Celestron sells the 15x70 and 20x80 combination in at least two separate tiers: a standard SkyMaster line and a SkyMaster Pro line. Per Celestron's own product pages, the Pro tier uses "superior optics, coatings, internal parts and housing materials" than the standard tier, and both Pro models add a Reflex Sight Rail (RSR), interchangeable flared eyecups, a nitrogen-filled waterproof body, and Celestron's "Fully Multi-Coated - XLT Coatings" lens treatment. The product this page's Amazon link actually points to -- the standard SkyMaster 15x70 -- ships with a shorter accessory list (tripod adapter, objective lens caps, rainguard, neck strap, lens cloth, and an instruction manual), and Celestron's own page for that standard model lists its coating simply as "Multi-Coated," its environmental protection as "Water Resistant" rather than "Waterproof," and does not list a nitrogen fill at all.

SkyMaster Pro 20x80 vs SkyMaster Pro 15x70: What Celestron's Pages State

Within the Pro line, the two models differ mainly in magnification, aperture, field of view, and weight. The Pro 20x80 is rated for 20x magnification through an 80mm (3.15") objective lens, with a 3.2° angular field of view and a 4mm (.15") exit pupil, per Celestron's own page. The Pro 15x70 is rated for 15x magnification through a 70mm (2.75") objective, with a wider 4.4° angular field of view and a larger 4.6mm (.18") exit pupil. A larger exit pupil generally means more of the light the objective lens gathers actually reaches your eye in dim conditions, while the Pro 20x80's larger objective gathers more total light to begin with -- the two numbers pull in different directions, which is why Celestron sells both rather than treating one as a strict upgrade of the other.

Weight is the other large difference: Celestron's page lists the Pro 20x80 at 86.4 oz (2449 g), almost double the Pro 15x70's 51 oz (1450 g). Both models share the same close-range convenience features per their respective pages -- a Reflex Sight Rail, interchangeable flared eyecups, a nitrogen-filled waterproof housing, and BaK-4 prisms with Celestron's XLT coatings -- so the decision between the two Pro models comes down to whether the extra aperture and magnification of the 20x80 is worth carrying almost twice the weight and losing more than a full degree of field of view.

Key Specs

Spec	SkyMaster Pro 20x80	SkyMaster Pro 15x70	SkyMaster 15x70 (standard -- this page's link)
Magnification	20x	15x	15x
Objective lens	80mm (3.15")	70mm (2.75")	70mm (2.75")
Angular field of view	3.2°	4.4°	4.4°
Exit pupil	4mm (.15")	4.6mm (.18")	4.7mm (.18")
Eye relief	15.5mm (.61")	17mm (.67")	18mm (.71")
Close focus	66.2 ft (20.2 m)	49.2 ft (15 m)	43 ft (13 m)
Weight	86.4 oz (2449 g)	51 oz (1450 g)	48 oz (1361 g)
Lens coatings	Fully Multi-Coated -- XLT	Fully Multi-Coated -- XLT	Multi-Coated
Environmental protection	Waterproof, nitrogen filled	Waterproof, nitrogen filled	Water Resistant
Extra hardware	Reflex Sight Rail, flared eyecups	Reflex Sight Rail, flared eyecups	Not listed

All figures are per Celestron's own product pages for each specific model.

What the Standard 15x70 Leaves Out

Set next to the Pro 15x70, the standard SkyMaster 15x70 that this page's Amazon link covers trades "Fully Multi-Coated - XLT Coatings" for plain "Multi-Coated," trades "Waterproof" for "Water Resistant," drops the nitrogen fill, and loses the Reflex Sight Rail and interchangeable eyecups, per Celestron's own pages for each. On the specific numbers in the table above, the standard model is not behind the Pro: its eye relief (18mm) and close-focus distance (43 ft) are actually slightly better than the Pro 15x70's (17mm and 49.2 ft), per Celestron's own figures for each model. And per both Celestron's page and the Amazon listing, the standard model keeps the same core optical numbers as the Pro: 15x magnification, a 70mm objective, and a 4.4° field of view. For a reader deciding purely on the headline 15x70-vs-20x80 question, the standard model answers it the same way the Pro model would; the Pro-specific extras matter most if coatings, full waterproofing, or the sight rail specifically are the deciding factors.

Checking Which One Fits How You'll Use It

Two numbers do most of the deciding. Field of view tells you how much sky you see at once -- useful for sweeping star fields, locating comets, or scanning the Milky Way, which is how the Amazon listing frames the standard 15x70's intended use. Weight tells you whether you can hold the pair steady by hand or need a tripod: Celestron's page lists a tripod adapter as included on every model here, so mounting either pair is already accounted for, but the 20x80's 86.4-ounce weight, per Celestron's page, is heavy enough that, in practice, a tripod becomes more of a practical necessity than an option for extended sessions, while the 15x70's 48-to-51-ounce weight, depending on version, is light enough to hand-hold for short stretches.

If you want the widest view of a star field and the lightest pair to carry, the 15x70 numbers -- in either the Pro or standard version -- are the ones to check against your own expectations. If you want more light gathered per look and more magnification, and you don't mind the tripod and the weight, the 20x80's numbers are the ones that matter, keeping in mind that this page has no Amazon link to a specific 20x80 listing to check.

What Stands Out

• The field-of-view gap is over a full degree. 4.4° on the 15x70 versus 3.2° on the 20x80, per Celestron's own pages -- a real difference when you're sweeping for a comet or a star cluster rather than centering on one object.
• The Pro tier adds real hardware, not just a name. A Reflex Sight Rail and interchangeable flared eyecups appear on both Pro models' pages and not on the standard 15x70's page.
• Weight roughly doubles from the 15x70 to the 20x80 within the Pro line (86.4 oz vs 51 oz, per Celestron's own figures) -- the single biggest practical difference between the two sizes Celestron's Pro-line pages give numbers for.
• The standard 15x70 keeps the same core numbers as the Pro 15x70 -- 15x magnification, 70mm objective, 4.4° field of view -- while giving up weather sealing and included hardware, per both Celestron pages.
• Every model in this comparison lists a tripod adapter as included, per Celestron's pages, so mounting isn't an extra purchase either way.

Where It Might Not Fit

• Neither 20x80 model has an Amazon link on this page. If you specifically want the 20x80, this page can describe Celestron's own published specs for it but can't point you to a current listing.
• The 20x80's narrower field and heavier body work against quick handheld sweeps. Celestron's own weight and field-of-view figures make a tripod the more realistic way to use it for any length of time.
• The standard 15x70 doesn't match the Pro 15x70 on weatherproofing or included hardware, per Celestron's own pages for each, even though the core optics are the same.

How It Compares to Other Binoculars on This Site

For a wider look at how the 10x50, 15x70, and 20x80 sizes compare across more than just Celestron's own two tiers, this site's binocular-size breakdown covers the aperture-versus-portability trade-off in more depth. And since any pair of astronomy binoculars left outside on a clear night will eventually fog up, this guide to dew control is worth reading before your first long session with either size.

Verdict

For most readers asking this exact question, the 15x70 -- in either the Pro or standard version -- is the easier pair to live with: it's lighter, shows more sky at once per Celestron's own field-of-view figures, and still gathers enough light for comet-hunting and wide star fields, which is how the Amazon listing frames the standard 15x70's intended use. Check the current price of the Celestron SkyMaster 15x70 on Amazon to see the listing this page is actually linking. The 20x80's extra aperture and magnification are real advantages per Celestron's own numbers, but they come with close to double the weight -- heavy enough, in practice, that a tripod stops being optional for long sessions -- and this page has no current Amazon listing for that size to point to.

Check the current price of the Celestron SkyMaster 15x70 on Amazon before deciding between the two sizes.

See our full shortlist of gear this site has reviewed.

Sources

• Celestron -- product page for the SkyMaster Pro 20x80mm Porro Binoculars (celestron.com).
• Celestron -- product page for the SkyMaster Pro 15x70mm Porro Binoculars (celestron.com).
• Celestron -- product page for the SkyMaster 15x70mm Porro Binoculars, standard line (celestron.com).
• Amazon product listing for the Celestron SkyMaster 15x70 Binoculars, per First Light's cleaned copy of the listing.