Ephemis
Plan your astrophotography
Free
Find tonight’s best deep-sky targets, ranked for your telescope, your sky, and the Moon. Fully offline, with altitude charts, mosaics, and session logging.
Ephemis ranks the best deep-sky targets to photograph tonight — matched to your gear, your sky, and the Moon. It does the planning math so you can spend clear nights imaging instead of guessing.
Point it at a date and location, tell it about your telescope and camera, and Ephemis scores thousands of galaxies, nebulae, and clusters by how well they fit your field of view and how long they stay high in a dark sky.
WHAT IT DOES
• Ranks 16,000+ deep-sky objects for any night, at any site
• Scores each target on framing, altitude, available dark hours, Moon interference, and feasibility for your setup
• Models real darkness — astronomical, nautical, or civil twilight — not just sunset to sunrise
• Full Moon avoidance with broadband and narrowband profiles, plus per-night Moon tracks
• Field-of-view fit for your exact optic and sensor, including multi-panel mosaics
• Altitude charts with transit time, meridian flip, and your local horizon limits
• Save targets to a project list, set hour goals, and log your imaging sessions
• Best Nights view to find when a target peaks over the coming weeks
BUILT FOR THE FIELD
• Fully offline — every catalog is bundled, so it works with no signal under a dark sky
• Messier, NGC/IC, Sharpless, Barnard, van den Bergh, LBN and LDN catalogs included
• Native on iPhone, iPad, and Mac, with iCloud sync of your rigs, sites, and targets
• Deep links to AstroBin references and Clear Outside forecasts
Set up your rig and observing site once, and every night Ephemis tells you exactly where to point.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Moon-aware planning in My Targets: see broadband and narrowband moon-safe hours beside tonight's visibility, even for targets with logged sessions. Sort by either to find a suitable target. Near full Moon, broadband-safe hours count only when the Moon is below the horizon.
Open Moonlight & SNR from a saved target for an automatic, target- and night-specific reference: approximate integration time to match one moonless hour's signal-to-noise. Broadband uses a 400–700 nm reference; Hα and [O III] are illustrative narrowband examples. Matching the estimated SNR does not remove gradients or restore lost faint detail. Method and limits are available on demand.
The developer, David Roka, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- David Roka
- Size
- 5.7 MB
- Category
- Photo & Video
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - iPad
Requires iPadOS 17.0 or later. - Mac
Requires macOS 14.0 or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Ephemis