Equipment

Manage your telescopes, eyepieces, Barlow lenses, and filters to automatically calculate magnifications, fields of view, and optical limits.

Telescopes

Open the equipment manager via the hamburger menu → “Equipment” → “Telescopes” tab.

Adding a Telescope

Tap “Add Telescope” and enter:

The app automatically calculates:

• Focal ratio (f-ratio)
• Maximum useful magnification (approx. 2× aperture in mm)
• Dawes limit (resolving power in arcseconds)
• Light gathering power (compared to the naked eye)

Telescope Details

Tap a telescope to see details, including a table of all eyepiece combinations:

Color warnings for:

• Red: Magnification exceeds the useful maximum
• Orange: Exit pupil > 7 mm (light misses the eye)

Default Telescope

Swipe right on a telescope to set it as the default. The default telescope is automatically entered when logging an observation.

Eyepieces

Switch to the “Eyepieces” tab.

Adding an Eyepiece

Default Eyepiece

Swipe right to set an eyepiece as the default.

Barlow Lenses

Switch to the “Barlows” tab.

Adding a Barlow

Barlow lenses are included in observation recommendations and displayed as combinations with eyepieces (e.g. “+2× Barlow — 240×”).

Observation Recommendations and Aperture

Observation recommendations take into account the aperture of your telescope. Magnification ranges are calculated dynamically based on the exit pupil:

• Magnification = aperture / exit pupil: A 200mm telescope delivers twice the magnification of a 100mm telescope at the same exit pupil
• Warning for insufficient aperture: If your telescope does not meet the minimum aperture for an object, a warning is shown (e.g. globular clusters typically require at least 100mm)
• Exit pupil in quality rating: Combinations with a very small exit pupil (< 1mm, image too dark) or very large exit pupil (> 7mm, light is lost) are downgraded in the rating

Default Barlow

Swipe right to set a Barlow as the default.

Filters

Switch to the “Filters” tab.

Adding a Filter

Filters are matched against observation recommendations — if a recommended filter is present in your equipment, it is displayed.

Default Filter

Swipe right to set a filter as the default.