Catadioptric telescopes
Eight inches with a hand control, or five inches driven from a phone?
Both fold a long focal length into a short tube, and both find objects for the observer. They differ in aperture, 203 mm against 127 mm, in corrector design, and in how they are told where to go: a NexStar+ hand control against a phone over Wi-Fi. Neither US listing publishes its focal length.
| Compared on | NexStar 8SE (11069) | SkyMax-127 AZ-GTi |
|---|---|---|
| Aperture | 8 in (203 mm), stated | 127 mm (5 in), stated |
| Folded focal length and ratio | Not published in the listing’s specification bullets. | Not published in the Amazon.com listing. |
| Corrector design | Schmidt-Cassegrain · StarBright XLT coatings | Maksutov-Cassegrain · 94% reflectivity mirrors · MHTC-coated corrector |
| Obstruction | Not published by the maker. | Not published by the maker. |
| Cool-down guidance | Not published by the maker. | Not published by the maker. |
| Tube weight | About 24 lb total, per the review in the listing | Mount 8.6 lb (3.9 kg), stated |
| Mount supplied | Computerized single-arm GoTo · NexStar+ with 40,000+ objects · SkyAlign | AZ-GTi Wi-Fi GoTo · 11 lb payload · Freedom Find encoders |
| Listed on amazon.com | Yes | Yes |
A tick means one listing published something the other did not, or published a better figure. It does not mean the product is better, and the column is not a score out of anything: a maker who says less loses lines here without losing a comparison. The two verdicts below are where the page is settled.
The aperture. Eight inches gathers about 2.6 times the light of five, and on planets, globular clusters and galaxies that is the figure that decides how much detail there is to see. SkyAlign and Solar System Align make it quick to start. Budget for a power supply and a second eyepiece.
The compact one that publishes its build. The listing gives the mirror reflectivity, the mount weight and an 11 lb payload, and the Freedom Find encoders let it be pushed by hand without losing alignment. Control is from a phone, which means one less thing to carry and one more that needs a charge.
About 2.6 times the light and 60% finer resolution. Globular clusters resolve more stars, galaxies show more structure, and Jupiter and Saturn show more detail on a steady night.
A Maksutov usually has a smaller central obstruction and a longer focal ratio, which suits planets and needs longer cool-down. A Schmidt-Cassegrain gives more aperture for the money. Neither listing here publishes its obstruction.
Yes, both, and neither listing says so. A closed tube brought from a warm house needs 30 to 60 minutes outside before the image settles; larger apertures take longer.
8-inch (203 mm) Schmidt-Cassegrain · computerized GoTo single-arm mount · 40,000+ objects · SkyAlign
Celestron's NexStar 8SE: an 8-inch Schmidt-Cassegrain with StarBright XLT coatings on a computerized single-arm GoTo mount, with the NexStar+ hand control, a 40,000-object database and SkyAlign.
Best for: Serious aperture that still fits in a car trunk and sets up in minutes
≈ $1,499
127 mm (5 in) Maksutov-Cassegrain · AZ-GTi Wi-Fi GoTo mount · 11 lb payload · mount 8.6 lb
Sky-Watcher's SkyMax 127 Maksutov-Cassegrain on the AZ-GTi, a Wi-Fi GoTo alt-azimuth mount controlled from a phone, with an 11 lb payload, Freedom Find encoders and an aluminum tripod.
Best for: Lunar, planetary and double-star observing from a small or awkward site, driven from a phone
≈ $839
Any figure written into the body of this page was true on the day it was written. The amount shown next to each instrument is requested from the retailer as the page loads, and it is that amount, not the text, that stands.
