Astro Tools

A small collection of tools I have built for astronomical photography and observation planning. More to come.

Capture Eclipse Visualizer (2026) - An interactive timeline view of CaptureEclipse XML scripts. Upload a script exported from Capture Eclipse, and see every photo plotted on a totality timeline with exposure-duration-scaled widths. You must be using at least version 2.2 of Capture Eclipse that support embedded absolute timings for the events.

This is just a way to visualize scripts generated with Robert J. Hawley’s Capture Eclipse software, to help optimize script editing. Credit goes back to Robert and Fred Espenak who have done the hard work implementing into software fairly complex solar eclipse timing calculations.

Resolution Limits Visualizer (2026) - Compares the achievable angular resolution of different camera and lens/telescope combinations. It combines seeing, guiding, diffraction, and sensor (pixel sampling) blur in quadrature.

Electron Count & SNR Visualizer (2026) - For a given camera, target and sky, estimates the per-pixel electrons (or ADUs) from signal, sky glow, thermal current and read noise, how each contributes to the total noise, and how the stacked SNR varies with sky brightness and sub-exposure length. Includes presets for popular targets and the Bortle sky-darkness scale.

Twilight vs Light Pollution Planner (2026) - For high latitudes around midsummer, when the Sun never reaches astronomical darkness: compares the zenith sky brightness of residual twilight against your site’s light pollution (Bortle/SQM) and moonlight, for any city and date. Shows the brightness components through one night with the crossover times where twilight stops being the limit, plus a full-year overview of each night’s darkest point and the dates when your site actually reaches its light-pollution floor. Twilight model calibrated against ESO Paranal measurements (Patat et al. 2006, via hnsky.org); moonlight from Krisciunas & Schaefer (1991).