Telescopes
Celestron Inspire 100AZ review
Nearly the same telescope as the DX 102AZ, minus the app that finds things and plus the bracket that photographs them.
By Scooter M. · published September 26, 2026
I'm not an astronomer and I don't have a lab. I'm someone who's genuinely into this — I read the manuals, compile the published specs, and do the arithmetic the box doesn't do for you. No lab coat. How we pick.
How this is funded. Lens & Lightyear earns a commission when you buy through a link on this page, at no extra cost to you. It does not change which products we pick or what we say about them — every card below carries a real reason to skip it. Prices are pulled live and were last verified October 18, 2026. Full disclosure.
The short answer
Buy the Inspire if someone in the house can already find things and wants to photograph them — the optics match Celestron's pricier DX 102AZ, it is 1.8 lbs lighter, and the phone adapter is built in. Buy the DX instead if nobody can navigate the sky, because its app solves that and this does not.
This is an unusually clean comparison to write, because Celestron sells two 660mm f/6.5 refractors that differ by 2mm of aperture and by almost nothing else optically. Everything that should decide your purchase is in the box, not in the tube.
The two near-twins, side by side
| Inspire 100AZ | StarSense Explorer DX 102AZ | |
|---|---|---|
| Aperture | 100mm | 102mm |
| Focal length / ratio | 660mm, f/6.5 | 660mm, f/6.5 |
| Eyepieces supplied | 20mm + 10mm (33x / 66x) | 25mm + 10mm (26x / 66x) |
| Published ceiling | 241x | 240x |
| Limiting stellar magnitude | 12.5 | 12.5 |
| Finding help | StarPointer Pro red dot | Red dot plus the StarSense app |
| Slow-motion controls | None — panning handle with clutch | Dual axis |
| Phone photography | Integrated smartphone adapter | Not included |
| Also in the box | Erect image diagonal, red LED flashlight | — |
| Kit weight | 12.4 lbs | 14.2 lbs |
| Price bracket | Lower | Top of our range |
Celestron's published specifications for items 22403 and the DX 102AZ, linked below. Bold marks the advantage where there is one. The aperture difference is about 4 percent of the light — 100 squared against 102 squared.
Two telescopes, one optical formula, two completely different evenings. The DX spends its extra money on finding things; the Inspire spends its on recording them and on being lighter to carry.
How much of the telescope is in the box
Our standing arithmetic: focal length divided by eyepiece focal length, set against the manufacturer's own published highest useful magnification. Celestron's 241x here is the usual 60x per inch — 3.94 inches times 60 is 236, published as 241.
| Combination | Magnification | Exit pupil | Share of the 241x ceiling |
|---|---|---|---|
| 20mm eyepiece | 33x | 3.03mm | about 14% |
| 10mm eyepiece | 66x | 1.52mm | about 27% |
| No Barlow supplied | — | — | — |
Exit pupil is aperture divided by magnification. Our arithmetic on Celestron's published figures.
Twenty-seven percent is low, and it is the same gap the DX 102AZ has for the same reason: no Barlow in a box at this price. One eyepiece around 6mm would give 110x here, comfortably inside the ceiling, and our Barlow lens guide covers the cheaper alternative of doubling what you already own.
What f/6.5 means for what you see
A two-element achromatic lens cannot focus every color at the same point, and the residual error grows as the lens gets faster. The guideline we use across this site is roughly f/3 per inch of aperture before it stops mattering — for a 3.94-inch lens that points at about f/12.
This telescope is f/6.5, so by design expect a violet edge on the Moon's limb and around bright planets. That is not a defect and it is not unique to the Inspire: the DX 102AZ review says exactly the same thing about the same focal ratio. It is the cost of keeping a 100mm tube short enough to sit on a 32-inch tripod.
A note on tube length, because our own pages could mislead you
Celestron lists the optical tube at 436mm for a 660mm focal length, and on our PowerSeeker 127EQ page we treat exactly that kind of gap as a red flag. It is not one here, and the difference is worth understanding.
In a refractor the light keeps traveling after it leaves the tube — through the focuser drawtube and then through a 90 degree diagonal — and that path is part of the focal length. A 436mm tube plus focuser plus diagonal reaching 660mm is ordinary. In a Newtonian the light folds inside the tube, so a 1000mm focal length in a 436mm tube means an optical element is stretching it. Same arithmetic, opposite conclusion, because the light paths are different.
The phone adapter, and what it will actually photograph
The integrated adapter is the Inspire's signature feature and the reason to choose it over the DX, so it deserves an honest account rather than a sales line.
- The Moon: genuinely good. Bright enough for a short exposure, and 100mm at 33x frames it well. This is the shot people actually want and it works.
- Jupiter and Saturn: a bright blob. Small on a phone sensor, and without tracking the planet drifts out of frame while you fiddle.
- Deep sky: no. Galaxies and nebulae need tracking mounts and stacked long exposures. No telescope on this page does that, and any guide implying otherwise is selling you something.
- Use the self-timer. Tapping the screen shakes the whole telescope — the single biggest cause of blurred results. Our smartphone adapter guide covers the rest.
Aperture per pound
| Model | Aperture | Kit weight | Aperture per pound |
|---|---|---|---|
| StarSense LT 114AZ | 114mm | 10.4 lbs | about 11.0 mm/lb |
| Inspire 100AZ | 100mm | 12.4 lbs | about 8.1 mm/lb |
| LT 80AZ | 80mm | 9.2 lbs | about 8.7 mm/lb |
| DX 102AZ | 102mm | 14.2 lbs | about 7.2 mm/lb |
| AstroMaster 70AZ | 70mm | 10.8 lbs | about 6.5 mm/lb |
Our arithmetic on published apertures and published total kit weights. The Inspire carries its aperture more efficiently than the DX it otherwise matches.
Who this is for
| Situation | Verdict |
|---|---|
| An adult or teen who knows the sky and wants photos | Buy it. Same optics as the DX, lighter, with the bracket built in. |
| Nobody in the house can find anything | The DX 102AZ — the app is the whole point. |
| A child will use it alone | Not this one. 12.4 lbs and a red dot finder. See ages 11-12. |
| Lunar detail with no false color | The AstroMaster 70AZ at f/13, for far less. |
| Faint galaxies are the goal | A reflector — see telescopes for deep space. |
| Daytime use as well as night | A strength. The erect image diagonal is included, so the view is the right way up. |
A note on availability
Celestron's own store currently lists this model as out of stock while it remains available at retail, which is why our button shows what the price feed sees today rather than a number we typed. If it is gone when you click, both alternatives above are stocked and reviewed here.
What we did and did not do
We have not handled this telescope. Every specification above was read from Celestron's own published page for item 22403, linked below and checked on the date at the top of this page; the magnifications, exit pupils, light ratios and shares are arithmetic on those figures, shown so you can repeat them. The note on false color is what the published focal ratio implies, not an observation we made.
No price appears in this prose. Live figures come only from our price feed with the date they were checked, and where there is no live figure the button reads *check price*. Our full method is on the methodology page.
The picks in full
Pick 1
Celestron Inspire 100AZ
An adult or teen who can find things, and wants to photograph them
The arithmetic
On paper this is the StarSense Explorer DX 102AZ with the app removed and a camera bracket added: the same 660mm focal length, the same f/6.5, the same published 12.5 limiting stellar magnitude, and a 241x ceiling against the DX's 240x. The aperture difference is 100mm against 102mm, which by the square of the ratio is about 96 percent of the light — a difference no eye will detect. What differs is the weight (12.4 lbs against 14.2) and what Celestron puts in the box: an integrated smartphone adapter, an erect image diagonal and a red LED flashlight instead of a phone dock and guidance app. The supplied 20mm and 10mm give 33x and 66x, so the kit reaches about 27 percent of its own ceiling with no Barlow.
Read the specification sheet next to the StarSense Explorer DX 102AZ and the two are near-twins: 660mm focal length, f/6.5, a published 12.5 limiting stellar magnitude, and ceilings of 241x here against 240x there. The aperture gap is 100mm against 102mm, which works out to about 96 percent of the light — a difference no eye will ever notice.
What Celestron puts in the box instead of a guidance app is a camera rig: an integrated smartphone adapter, an erect image diagonal so the view is the right way up, a StarPointer Pro finder and a red LED flashlight. For a household that already knows where Jupiter is, that is a more useful bundle than a dock.
It is also lighter than the DX — 12.4 lbs against 14.2 — with a 4.9 lb tube on an 8 lb mount and tripod, and it uses the same 32 to 51 inch steel-legged tripod as the rest of this Celestron tier.
The honest gaps: no Barlow, so the box reaches about 27 percent of its own 241x ceiling; optics Celestron calls *fully coated* rather than fully multi-coated; and no slow-motion controls, so tracking at high power is a hand-nudge job.
Skip it if
Nobody in the house can navigate the night sky. This has a red dot finder and nothing else — no app, no slow-motion controls — and finding a faint target with a red dot is a skill, not a feature.
| Item number | 22403 |
|---|---|
| Optical design | Refractor |
| Aperture | 100mm (3.94") |
| Focal length | 660mm (25.98") |
| Focal ratio | f/6.5 |
| Optical tube length | 436mm (17.2") |
| Optical coatings | Fully coated |
| Eyepieces supplied | 20mm (33x) and 10mm (66x) Kellner |
| Barlow | Not included |
| Diagonal | Erect image 90 degree, 1.25" |
| Finderscope | StarPointer Pro red dot |
| Smartphone adapter | Integrated |
| Mount | Manual alt-azimuth, panning handle with clutch |
| Tripod | 812.8mm-1295.4mm (32"-51") height range, 1.25" steel legs |
| Highest useful magnification | 241x |
| Lowest useful magnification | 15x |
| Limiting stellar magnitude | 12.5 |
| Light gathering power | 212x the human eye |
| Optical tube weight | 4.9 lbs (2.2 kg) |
| Total kit weight | 12.4 lbs (5.62 kg) |
| Also included | Red LED flashlight, folding accessory tray |
| What the box does not do | No Barlow, no app guidance and no slow-motion controls — pointing is by hand on a panning handle with a clutch. The optics are "fully coated" rather than fully multi-coated, and at f/6.5 this is a fast achromatic doublet, so expect some violet fringing on the Moon and bright planets by design. Nothing needs collimating, ever. |
Specifications from Celestron — Inspire 100AZ specifications. We have not handled this one — everything above is the published spec sheet plus our own arithmetic on it.
Pick 2
Celestron StarSense Explorer DX 102AZ
The same optics when nobody can find anything
The arithmetic
The jump from 70mm to 102mm is the biggest single upgrade on this site: light-gathering scales with the square of aperture, so a 102mm objective collects about 2.1 times what a 70mm does. The published limiting magnitude moves from 11.7 to 12.5 and the useful ceiling from 165x to 240x. The cost is 14.2 lbs — this is a two-hands, one-trip-to-the-garden telescope, not a carry-it-yourself one.
The decision between these two is not optical. It is about who is standing in the garden.
The DX adds the StarSense app, which reads the sky through the phone camera and walks you to a target with arrows, plus dual-axis slow-motion controls — geared knobs that creep the tube along instead of pushing it. At 66x and above that is the difference between following Jupiter and chasing it.
What it gives up is the Inspire's camera bracket, the erect image diagonal and the red flashlight, and it asks for a compatible phone and more money.
Both ship without a Barlow and both land near a quarter of their published ceiling, so the eyepiece purchase applies either way. Full review.
Skip it if
The available phone is older than an iPhone XR or runs below Android 12, or weight matters. At 14.2 lbs it is 1.8 lbs heavier and it costs meaningfully more for optics that are, on paper, the same.
| Optical design | Refractor |
|---|---|
| Aperture | 102mm (4.01") |
| Focal length | 660mm (25.98") |
| Focal ratio | f/6.5 |
| Eyepieces supplied | 25mm (26x) and 10mm (66x) |
| Finderscope | StarPointer red dot |
| Mount | Manual alt-azimuth |
| Tripod | 1244.6mm (49") max height |
| Highest useful magnification | 240x |
| Limiting stellar magnitude | 12.5 |
| Total kit weight | 14.2 lbs (6.44 kg) |
| What the box does not do | No Barlow in the box, so the supplied top magnification is 66x against a 240x ceiling — you will want a shorter eyepiece eventually. At 14.2 lbs assembled, a child under about ten will not be setting this up alone. |
Specifications from Celestron — StarSense Explorer DX 102AZ specifications. We have not handled this one — everything above is the published spec sheet plus our own arithmetic on it.
Pick 3
Celestron AstroMaster 70AZ
Cleaner lunar views for a fraction of the money
The arithmetic
The number that separates this from every other 70mm on the site is the focal length: 900mm, where the AstroMaster LT 70AZ is 700mm and the Travel Scope 70 is 400mm. That makes it f/13 — the slowest, most color-corrected refractor we list. The supplied 20mm and 10mm give 45x and 90x, both inside Celestron's published 165x ceiling, so the box reaches about 55 percent of the telescope with no Barlow needed. The cost is carried in pounds: 10.8 lbs for 70mm of aperture works out to roughly 6.5mm per pound, the lowest ratio on this site.
The cheap alternative that beats both of these at one specific thing. At f/13 the AstroMaster 70AZ is slow enough that false color effectively disappears, where both 660mm f/6.5 telescopes on this page will show a violet edge on the Moon's limb by design.
It also supplies more usable magnification: 45x and 90x against the Inspire's 33x and 66x, because 900mm of focal length divides further.
What you give up is light — 70mm against 100mm is about half — and 10.8 lbs of weight for the privilege, which is the worst aperture-per-pound ratio on this site.
Skip it if
Deep-sky objects or photography matter. 70mm collects roughly half the light of 100mm, and there is no phone bracket in the box.
| Item number | 21061 |
|---|---|
| Optical design | Refractor |
| Aperture | 70mm (2.76") |
| Focal length | 900mm (35") |
| Focal ratio | f/13 |
| Optical tube length | 685mm (27") |
| Optical coatings | Fully coated |
| Eyepieces supplied | 20mm (45x) and 10mm (90x) |
| Barlow | Not included |
| Diagonal | Erect image 90 degree, 1.25" |
| Finderscope | StarPointer red dot |
| Mount | Manual alt-azimuth, panning handle with clutch |
| Tripod | 812.8mm-1295.4mm (32"-51") height range, 1.25" steel legs |
| Highest useful magnification | 165x |
| Lowest useful magnification | 10x |
| Limiting stellar magnitude | 11.7 |
| Light gathering power | 100x the human eye |
| Total kit weight | 10.8 lbs (4.9 kg) |
| What the box does not do | No Barlow, and the optics are "fully coated" rather than fully multi-coated — a single-layer coating that passes slightly less light than the multi-coated glass on Celestron's dearer models. The long 685mm tube catches wind and swings the eyepiece through a wide range of heights as it tilts, which a short child will feel. Being a refractor there is nothing to collimate, ever. |
Specifications from Celestron — AstroMaster 70AZ specifications. We have not handled this one — everything above is the published spec sheet plus our own arithmetic on it.
Questions people actually ask
- Is the Celestron Inspire 100AZ a good telescope?
- Yes, for someone who can already find things in the sky. It has the same 660mm f/6.5 optics and the same published 12.5 limiting magnitude as Celestron's pricier StarSense Explorer DX 102AZ, weighs 1.8 lbs less, and includes an integrated smartphone adapter, erect image diagonal and red flashlight.
- What is the difference between the Inspire 100AZ and the StarSense Explorer DX 102AZ?
- Optically almost nothing — 100mm against 102mm is about 4 percent of the light, on the same 660mm f/6.5 tube. The DX adds the StarSense finding app and dual-axis slow-motion controls; the Inspire adds a built-in phone adapter, an erect image diagonal and a red flashlight, and is lighter and cheaper.
- What magnification does the Inspire 100AZ give?
- 33x with the supplied 20mm eyepiece and 66x with the 10mm, from its 660mm focal length. Celestron publishes a 241x ceiling, so the box reaches about 27 percent of the telescope's stated limit — a 6mm eyepiece would add about 110x.
- Can you take photos with the Inspire 100AZ?
- Of the Moon, yes — the integrated smartphone adapter holds the phone steady over the eyepiece and lunar detail photographs well. Planets come out as small bright blobs, and galaxies and nebulae need tracking mounts and long exposures no telescope at this price provides.
- Does the Inspire 100AZ show false color?
- Some, by design. An achromatic doublet needs roughly f/3 per inch of aperture before color error becomes negligible, which for a 3.94-inch lens is about f/12. At f/6.5 expect a violet edge on the Moon's limb and bright planets, exactly as on the DX 102AZ.
- Is the Inspire 100AZ good for a child?
- As a shared telescope with an adult setting it up, yes — and the erect image diagonal makes it usable in daylight. As a child's own first telescope, no: 12.4 lbs, no slow-motion controls, and finding targets with a red dot finder is a skill that takes practice.
Sources
Read next
Where to go from here
- Celestron StarSense Explorer DX 102AZ review
102mm of sealed refractor on the steadiest mount in the StarSense range. What dual-axis slow-motion controls are worth, and why a cheaper sibling out-apertures it.
- Celestron AstroMaster 70AZ review
70mm at 900mm focal length — f/13, the slowest refractor on this site, with 45x and 90x in the box against a 165x ceiling. Excellent on the Moon, heavy for what it gathers.
- Smartphone telescope adapters: which one fits, and what it will really photograph
Eyepiece clamp range is the spec that decides fit, and almost nobody checks it. The two Celestron adapters compared, plus an honest account of what a phone can and cannot capture.
- The best telescopes under $500
Between $200 and $500 you can have aperture, a parabolic mirror, or guided finding — but not all three. What each choice costs, and who should make which.
- Refractor or reflector for a child?
Mirrors are cheaper per millimeter of aperture; lenses never need aligning. Which trade suits which child, with the arithmetic on both.
- The best kids' telescope to see planets
Planets are the one thing every child asks about. Which telescopes show them properly, and what Jupiter and Saturn genuinely look like at this aperture.