Originally Posted by chris murphy
...the 25x MC is about a third cheaper than this at around £100. I have seen very little mention of this eyepiece in use....does anyone have experience with this EP or is it cheap because it's cack and no-one uses it?
I have that one, along with many others. It is a "conventional" eyepiece, which is to say not officially wide field, long eye-relief, or optically complicated. It is one of the oldest Fieldscope eyepiece still (or recently) in production, introduced (along with the short 40x with no eye-relief) for use as a 20x with the original Fieldscope. Nevertheless, it is an excellent eyepiece. The angular FOV is identical to the 30x WF/MC/DS model so it is plenty wide, but obviously the magnification is a bit lower. The eye relief is the same as the 30x WF/MC models, so adequate for most glasses wearers (~15+ mm). And despite its simple design, it has excellent sharpness across the field, comparable to the 30x WF and MC models (but not as flat as the 30x DS). I don't know how easy it is to find or what it goes for these days, but it used to be quite inexpensive.
Here is a picture of the eyepiece (it is #1) along with the later wide field MC models (which are more bulky because of twist up eyecups, and have updated coatings, but optically design otherwise identical to their WF predecessors). I really like the 24/30x MC and the 24/30x WF that it replaced.
Here are the DS models. I really like the 16/24/30x DS