Assertion: inexpensive eyepiece | /r/HasProperty | great performers
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text: Then better inexpensive eyepieces such as Edmunds Rank Kellner Eyepiece, Koenig, Koenig II (University optics), Erfle (a design going back to WW1, newer ones can be great performers, Plossl (been around for quite some time but did not become popular until about 1984 when Clave Paris came out with a premium design) there are many types, brands..even the inexpensive ones can be great performers.