The SWAN 2", 33mm eyepiece from William Optics is a very high quality wide angle eyepiece. With a 72° field of view, it offers a vast panorama for observing extended deep sky objects for example.
The lens surfaces are all multi-coated (FMC coating), offering high light transmission. The eyepiece gives high image quality with equally good contrast. The anti-reflective black coating is an additional plus.
The eyepiece has no problems when used with fast telescopes and is excellent from f5 up. The rubber eyecups can be folded down and the specially roughened surface of the eyepiece provides a secure grip.
It has a very comfortable-to-use 25mm of eye relief.
According to the manufacturer's specifications, the five elements in the eyepiece are arranged in four groups.
These Williams eyepieces are built to be parfocal with each other. That means they do not have to be refocused when switching from one eyepiece to another.
weight: 410g
Our expert comment:
Compare: you can get a similar eyepiece which is better value for money
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