AstroLabSouth African astronomy
Know your setup. Plan your image.
Explore optics, exposure, seeing and framing before heading outside.
Explore tonight’s skyTools for your next clear night
Free to use. No account needed.
Observing
Telescope Calculator
Magnification, focal ratio, exit pupil and field of view.
TonightClear Sky Indicator
South African cloud, wind and observing conditions.
TonightMoon & Darkness Planner
Find moonless hours and astronomical darkness.
ImagingAstrophotography Field of View
Frame a target with your telescope and camera.
ObservingDew Risk Calculator
Estimate the dew point and condensation risk.
TonightWhat Can I See Tonight?
Explore 250 catalogue objects on an interactive sky map.
ImagingBarlow / Reducer Calculator
Compare the effect of optical multipliers on your setup.
ImagingSub-exposure Optimizer
Balance read noise, sky brightness and exposure length.
TonightPlanetary Seeing Forecast
Upper-air forecasts for high-resolution observing.
ObservingEyepiece View Simulator
Compare the apparent views of the Moon and planets.
ImagingDeep-Sky Exposure Planner
Plan total integration time for your target and equipment.
TonightMonthly Night-Sky Guide
Seasonal targets, lunar phases and a South African sky archive.