Magna Calc vs Star Archive

Astronomers often need to calculate the magnification derived from their telescope focal length and eyepiece. MagnaCalc provides an easy way to calculate this value for both amateur and professional astronomers. Additionally, Magna Calc provides a 2x to 5x Barlow lens option. Whether you're an amateur or professional astronomer, you'll find Magna Calc helpful in your everyday passion for astronomy. Magna Calc Features... - Telescope Focal Length (in Millimeters) - Eyepiece Focal Length (in Millimeters) - Barlow Lens Option (1x, thru 5x) - Magnification Calculation

An app for visual astronomy — observing through a telescope or binoculars with your own eyes. · Sky chart — 5.5 million stars with your own fields of view overlaid, opened from plans, observing and object pages. · Plan and recommend — only what your aperture can show under your site's sky (1,272 objects judged in advance), placed into hour slots, rehearsed on the chart. · Observe and record — step through objects on the chart, check, rate and write; review by night or by object. ■ A built-in sky chart · About 5.5 million stars to 13th magnitude and 16,000+ deep-sky objects. Drag and pinch anywhere. · Sky as it looks right now (zenith up) or north up — one tap on the compass at top left. · Build fields of view from your telescope, eyepieces and finder and overlay several at once. Plan objects as rings, observed ones checked. · Open the chart from a plan, the observing screen or an object page, and come straight back. ■ One unbroken night · Plan — added objects settle into hour slots on their own; drag to rearrange. Tap an object for its altitude curve and suggested magnification right there. · Rehearsal — walk the night on the chart before you leave. Course editing handles hour slots, order and start stars on one screen. · Observing — step through objects on the chart, check them off, rate and write notes. Dictate by voice. · Records — enter the night's conditions once, then review by night or by object. Long-term plans spanning months, too. ■ Data and learning · 2,400+ visual guides — how to find it and what each aperture shows. 4,600+ observing points to rate. · Lists such as Messier, Caldwell, Herschel 400 and 1001, plus your own lists and courses. · Star hopping with 126 routes (using the chart's field-of-view settings); Messier marathon prep and a 110-object night. ■ Also Night mode (red screen, shake to toggle, automatic after sunset) · six themes · sketch albums · eyepiece-view simulator · tonight's clouds and seeing · real-time planets · spreadsheets in and out, full backup · on a bigger screen at starnotearchive.com · Korean, English and Japanese. Free. No ads, no purchases. No account in the app; make a web account only if you want the website. Records stay on your phone; only what you send goes up to the web (site names visible only to you). With weather on, the forecast point's location is passed to the weather service. The 13th-magnitude star data downloads only when you ask. Made as a hobby by one observer.