Your telescope. Your eyepieces. One field sheet.
Turn the eyepieces you already own into a comparison table and printable observing cards. No sky map to learn.
Try 3 decks/day without signing up. Create a free account for 50 decks/month. Your setup is saved only when you choose; no account key is saved.
The example uses a 1000 mm telescope. Its 25 mm eyepiece gives 40× power; a 60° apparent field estimates a 1.5° true field.
Enter your own setup and build a deck to compare power, exit pupil and framing. Then take the printable cards outside.
Which eyepiece gives the smallest field that fits your target and chosen margin? What magnification and exit pupil does each setup produce?
This is a geometric planning tool. It does not forecast visibility, weather, altitude, seeing or telescope performance. Apparent-field calculations are approximate; a supplied field stop takes priority.
Print one card per target with space for time, conditions and notes. Name targets yourself: no catalog account or external connection is needed.