Brightwell Dayspring 7 mm wide-field eyepiece, with soft pouch

Specifications

Description

The Dayspring 7 mm is a five-element wide-field eyepiece with a 60-degree apparent field and a 1.25 in barrel. It gives a wider view than a standard Plössl at the same focal length, which makes it easier to keep a target in view as the telescope tracks across the sky. The barrel is threaded for standard 1.25 in filters. It is a practical choice for a second eyepiece in a set that starts with a longer focal length.

A 7 mm eyepiece gives high power. In a 1,200 mm telescope it produces 171x, and in a 2,032 mm Schmidt-Cassegrain it produces 290x. At that magnification the true field narrows to about 0.35 degrees in the 1,200 mm telescope, or roughly 21 arcminutes, which is about two-thirds of the apparent diameter of the Moon. Use this eyepiece for compact targets such as planetary disks, double stars, and small globular clusters on nights when the air is steady.

The design uses five elements with fully multi-coated lens surfaces and blackened barrel edges to limit internal reflections. The 6.8 mm field stop sets the true field at the focal plane. In telescopes slower than about f/6 the image is sharp across most of the field. In faster telescopes, expect some softening and field curvature toward the edge, particularly in fast Newtonians.

Eye relief is 13 mm, which suits observers who do not wear glasses. Eyeglass wearers may find the eye point tight, so test the eye position before relying on the full field. The rubber eyecup twists up to block stray light and can be removed for a closer eye position. At 165 g, the eyepiece is light enough for most compact focusers and diagonals.

About this configuration

This listing covers one configuration of the Brightwell Dayspring 7 mm wide-field eyepiece, defined by its case, eyecup, finish, and edition year. The soft pouch keeps dust off the eyepiece and fits in a jacket pocket during a session. A soft pouch protects the lenses from scratches when you carry the eyepiece between the car and the telescope. The fold-down rubber eyecup blocks stray light, and you can fold it back if you observe with glasses.

The black body with a color ring lets you tell focal lengths apart quickly under a red flashlight. This is the 2023 edition of the Dayspring line, the earliest version that is still listed in the catalog. 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 rubber eyecup
• Top and bottom dust caps
• Padded storage case
• Soft padded pouch

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 across most of the field at f/6 and slower; softer at the edge in faster telescopes.