Halden Sable 7 mm wide-field eyepiece, with hard case

Specifications

Description

The Sable 7 mm is a six-element wide-field eyepiece with a 52-degree apparent field and a 1.25 in barrel. Its 6.5 mm field stop sets a true field that stays narrow enough for planetary and double-star work while keeping the view comfortable. It is designed for observers who want more magnification than a standard 10 mm eyepiece provides without giving up contrast or edge control.

A 7 mm eyepiece gives high power in most telescopes: 86x in a 600 mm refractor, 143x in a 1,000 mm telescope, and 286x in a 2,000 mm Schmidt-Cassegrain. At these magnifications, atmospheric steadiness matters more than optical design, so you should choose the power to suit the night. In a 1,000 mm telescope, the true field of 0.37 degrees is enough to frame a planetary disk or a tight double star with room to spare.

The six-element design uses a field lens group and a field-flattening arrangement to keep stars sharp to near the edge in telescopes slower than about f/7. In faster systems, some edge softness and mild field curvature remain, and you may notice them more in a fast Newtonian. All glass surfaces are fully multi-coated, and the internal baffles are blackened to reduce scattered light.

Eye relief is 11 mm, which suits most observers who do not wear glasses and works for many who do with the eyecup folded down. The fold-down rubber eyecup is standard. The barrel is threaded for standard 1.25 in filters, and the eyepiece weighs 110 g, so it balances well in lightweight diagonals and focusers.

Because the eyepiece is compact, it fits easily in a travel case alongside a 10 mm and a 25 mm eyepiece. Keep the dust caps on when it is not in use, since the field lens is exposed in the barrel and collects dust quickly.

About this configuration

All configurations of the Halden Sable 7 mm wide-field eyepiece share the same optical design; the options change the eyecup, the case, and the finish. The hard foam-lined case protects the eyepiece from knocks during travel and stacks neatly with other cases. A hard case keeps the eyepiece safe in a busy accessory box at a star party or an outreach event. A fold-down eyecup is simple and has no moving parts that can loosen in cold weather.

The silver anodized body is easy to find in a dark accessory case and wipes clean after dewy nights. The optics in the 2024 edition match the other years; the changes concern the housing only. To find the magnification, divide the focal length of your telescope by the eyepiece focal length in the specifications.

What's in the box

• Eyepiece with fold-down rubber eyecup
• Top and bottom dust caps
• Padded storage case
• Hard foam-lined case

Compatibility notes

• Fits any 1.25 in focuser, diagonal, or Barlow lens.
• The barrel accepts standard 1.25 in filters (M28.5 x 0.6 thread).
• Sharp to near the edge at f/7 and slower; some edge softness in fast Newtonians.