Assertion: eyepiece | /r/HasProperty | rare
Facets:
Source sentences:
text: The disadvantages are that these eyepieces are somewhat rare, extremely expensive, up to 5 lbs in weight, and that only a few telescopes have focusers large enough to accept them.
text: The disadvantages are that these eyepieces are somewhat rare, extremely expensive, up to 5 lbs in weight, and that only a few telescopes have focusers large enough to accept them.
text: These eyepieces are rare and only commonly used in observatories.