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Parts ranked by focal ratio

f/13
Celestron NexStar 4SE specifications has the highest focal ratio in the dataset, at f/13.

Which part has the highest focal ratio?

Celestron NexStar 4SE specifications, at f/13, tops the 15 parts we hold a published focal ratio for. The full ranking is below.

#PartsFocal ratio
1Celestron NexStar 4SE specificationsf/13
2Sky-Watcher Skymax 127 specificationsf/12.1
3Celestron StarSense Explorer LT 80AZ specificationsf/11.25
4Celestron NexStar 8SE specificationsf/10
5Celestron NexStar 6SE specificationsf/10
6Celestron NexStar 5SE specificationsf/10
7Celestron C6 optical tube specificationsf/10
8Celestron C8 optical tube specificationsf/10
9Celestron AstroMaster 114EQ specificationsf/8.77
10Celestron PowerSeeker 127EQ specificationsf/7.87
11Celestron StarSense Explorer 8-inch Dobsonian specificationsf/5.9
12Sky-Watcher Classic 200P (8-inch Dobsonian) specificationsf/5.9
13Orion SkyQuest XT8 Classic Dobsonian specificationsf/5.9
14Celestron AstroMaster 130EQ specificationsf/5
15Sky-Watcher Heritage 130P specificationsf/5

Data as of 2026-09-05.

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