FITS Blaster

FITS Blaster is a fast, focused image culling tool for astrophotographers. Open a folder of FITS files and instantly see which frames are keepers — and which ones to reject. MEASURE IMAGE QUALITY FITS Blaster analyses every frame directly from raw pixel data, computing FWHM (sharpness), eccentricity (round vs. elongated stars), signal-to-noise ratio, star count, PSF and background. No guessing — just numbers. FAST BY DESIGN GPU-accelerated rendering means even large 20-megapixel+ images appear instantly. The loading pipeline processes multiple frames in parallel so you spend your time reviewing, not waiting. CULL WITH CONFIDENCE The session chart gives you a visual overview of frame quality across your entire session. Drag across the chart to batch-reject outliers in one gesture. Set auto-reject thresholds and let FITS Blaster do the work. FILTER-AWARE FITS Blaster groups your frames by filter — Ha, OIII, SII, RGB, and more — so you can evaluate each filter channel independently. Perfect for narrowband and multi-panel workflows. BUILT FOR REAL SESSIONS - Recursive subfolder scanning for multi-night , multi-filter or multi-target sessions - Rejection moves files to a REJECTED subfolder — nothing is deleted - Undo rejection with a single key press - Configurable keyboard shortcuts for every action - Simple mode hides metrics for a clean, distraction-free view PRIVATE BY DESIGN No internet connection required. No analytics, no telemetry, no data collection of any kind. Your images and your data stay on your Mac. FITS Blaster Pro (annual subscription) unlocks unlimited frames per session and the full metrics suite. The free tier allows up to 50 frames so you can try before you subscribe.