Giordano Observatory · free tools
Field of view calculator
Scegli telescopio e camera e guarda il campo inquadrato su una vera foto del cielo: scala in ″/px, campionamento, mosaici e rotazione. Gratis, anche dal telefono.
Tools for amateur astronomers are on their way
Free tools for anyone who observes and photographs the sky, designed by our observatory: we're testing them with a small group of amateur astronomers before opening them to everyone.
- Which telescope is right for you5 questions and the 3 right telescopes, with the reasons why
- Field of viewYour telescope with any camera, on a real photo of the sky
- What to image tonightThe best objects from your location, with the Moon, comets and meteor showers
- Astronomy weatherClouds, humidity, dew and wind, hour by hour, with satellite and radar
- Sky chart and MoonTonight's sky, the Moon's phases and sky events for your calendar
- Camera databaseAstronomy cameras, DSLRs and mirrorless cameras compared
- 21 calculatorsMagnification, exposure times, backfocus, mounts and more
- Your observing logThe objects you've seen and imaged, with the 110-object Messier challenge
We'll let you know as soon as they're ready
How to use the field of view calculator
Choose your telescope, or a camera lens, and your camera: the sensor frame appears on the photo of the sky, with the object shown at its true size. You can move it, rotate it, plan a mosaic and copy the link to get back to the same framing later.
What it calculates
The field of view in degrees or arcminutes, the image scale in arcseconds per pixel, the sampling relative to the seeing, the effective focal length with reducers and Barlow lenses and, for visual observing, magnification, true field of view and exit pupil.
Planets, Moon and Sun
Search for Saturn, Jupiter or the Moon: you see them at their true size on the sensor, with the number of pixels they cover, the ideal focal ratio for your camera, the recommended Barlow and the date of the next opposition.
Data: object catalogue from Stellarium (SIMBAD/VizieR, CDS Strasbourg); Digitized Sky Survey sky photos (STScI/NASA) via hips2fits (CDS); sky map by Giordano Astronomia with ESA's Hipparcos and Tycho-2 star catalogues; places: GeoNames (CC BY 4.0); sky darkness from the NASA Black Marble 2016 night lights (VIIRS, NASA Earth Observatory / GIBS); ephemerides computed with J. Meeus's algorithms and JPL orbital elements. Camera data from the manufacturers' official spec sheets.
✦ Tools designed and developed by Mattia Toto for Giordano Astronomia · @toto.astrophoto