f/ Tools vs FlashFlashApp

f/Tools is a toolkit for digital and film photography. Explore depth of field, compare defocus across lenses, and try different shutter speeds before you shoot. Plan your prints and calculate flash exposure, with interactive diagrams that make photographic concepts easier to understand. Features: • Depth of field and hyperfocal distance See near and far focus limits and how they change with aperture, focal length, and focus distance. • Defocus comparison Explore how focal length, aperture, and subject distance affect blur, with a magnifier for a closer look. • Freeze motion Calculate the shutter speed needed to limit motion blur based on subject speed, distance, and focal length. • Motion blur Try different shutter speeds and visualize the resulting motion trail. • Diffraction and resolution Explore Airy disc size and estimated effective resolution as you change the aperture. • Framing and prints Calculate scene dimensions, adjust cropping, and find the circle of confusion and minimum resolution needed for your print size and viewing distance. • Flash exposure Calculate exposure at different distances using guide number, flash power, aperture, and ISO. • Your cameras and lenses Save your equipment and set lens limits for aperture, focal length, and focus distance. Get started quickly with built-in camera presets. Built-in help explains the controls, calculations, and photographic terms within each tool.

Know your flash settings before you shoot — not after three test frames. FlashFlash is a manual flash calculator built on the Guide Number method. It solves in both directions: POWER CALCULATOR Set your aperture. FlashFlash tells you exactly what power fraction to dial in — 1/4, 1/16, whatever the shot needs. APERTURE RECOMMENDER Set your power level. FlashFlash tells you exactly which f-stop to use. Battery-constrained, locked into a specific power level, planning a shot before you arrive — this is the tab for it. No test shots. No chimping. Enter your settings, read the answer, nail the exposure. WHAT YOU ENTER · Guide Number — type it manually or pick from 100+ built-in presets (Godox, Canon, Nikon, Sony, Profoto, Elinchrom, and more) · ISO · Aperture or power level — depending which tab you're on · Flash-to-subject distance · Flash zoom from 24 mm to 200 mm · Filter compensation for gels, diffusers, and softboxes WHAT YOU GET · The exact power fraction or f-stop, snapped to a real standard setting · Effective GN and Required GN — so you know exactly how much headroom you have · A live scene visualization: your flash, your subject, your light cone, updating in real time · A power bar showing at a glance how hard your flash is working ON CAMERA OR OFF FlashFlash always asks for flash-to-subject distance — not camera-to-subject. Because when your flash is on a stand three feet from your subject and you are eight feet away, those numbers are not the same. And that difference is everything. FULLY OFFLINE No account. No network connection. No subscription. One purchase. Your settings are saved on your device. Works anywhere you shoot.