Zoom eyepieces
The one that fits everything, or the one that states its field?
Identical focal length ranges, and almost no overlap in what the two listings publish. One gives the mechanical reach — both barrel sizes and a camera thread; the other gives the optical figure that a zoom is actually judged on, which is how much field it keeps at the long end.
| Compared on | Hyperion Universal Mark IV 8-24 mm | 8-24 mm zoom (93230) |
|---|---|---|
| Focal length range | 8 mm to 24 mm, continuously variable | 8 mm to 24 mm, continuously variable |
| Apparent field at both ends | The listing does not carry it | 40 to 60 degrees across the range, as the maker states it |
| Eye relief | Not published by the maker. | Fold-down eyecup, for use with or without spectacles |
| Parfocality | Not published by the maker. | Not published by the maker. |
| Action | 1.25 in and 2 in, both, with an M43 thread | Not published by the maker. |
| Barrel size | Not published by the maker. | 1.25 in |
| Coatings | Not published by the maker. | Multi-coated on every lens surface, per the maker |
| Body | The listing does not carry it | Not published by the maker. |
A tick means one listing published something the other did not, or published a better figure. It does not mean the product is better, and the column is not a score out of anything: a maker who says less loses lines here without losing a comparison. The two verdicts below are where the page is settled.
The one that goes everywhere. Fitting 1.25 in and 2 in focusers and carrying an M43 camera thread makes it the eyepiece that works on whatever is in the garage, and it is supplied with an extensive accessory set. It publishes no apparent field at all, which on a zoom is the figure a buyer most wants.
The one that answers the zoom question. Forty degrees at the long end rising to sixty at the short end is exactly what a zoom does and what most makers decline to print. It also names its coating and its eyecup, and it fits one barrel size only.
Because the field stop is fixed by the barrel while the focal length changes. At 24 mm the apparent field is at its narrowest — here 40 degrees — and it widens as the eyepiece is zoomed in.
A parfocal zoom holds focus as it is turned, so magnification can be changed without refocusing. Neither of these publishes it, which means it has to be found out at the eyepiece.
It matters if the telescope has a 2 in focuser and the observer does not want an adapter in the train. It does not widen the field: that is set by the eyepiece, not the barrel.
8–24 mm variable · 1.25 in and 2 in · M43 camera thread
An 8–24 mm zoom that fits both 1.25 in and 2 in focusers and carries an M43 camera thread, supplied with an extensive accessory set.
Best for: An owner of both 1.25 in and 2 in focusers who also photographs through the eyepiece
≈ $396 / €275
8–24 mm variable · 40°–60° apparent field · 1.25 in
An 8–24 mm zoom eyepiece in a 1.25 in barrel, multi-coated, with a fold-down eyecup and an apparent field running from 40 to 60 degrees across the range.
Best for: Observers who want to stop swapping eyepieces in the cold
≈ £125 / €126
Any figure written into the body of this page was true on the day it was written. The amount shown next to each instrument is requested from the retailer as the page loads, and it is that amount, not the text, that stands.
