A professional flash photography calculator designed for both digital and analog photographers. Calculate optimal flash power, aperture, and distance combinations with ease.

• Digital Mode: Quick ISO adjustment on main screen
• Analog Mode: Set film ISO once in settings

• Distance-first workflow - set your target distance and get optimal settings
• Multiple viable power/aperture combinations
• Real-time calculations using Guide Number formula
• Quick Power Reference table with color-coded power levels

• Configurable Guide Number for any flash
• Custom aperture and ISO ranges
• Adjustable distance range (0.3m to 20m)
• Priority weights (power efficiency vs depth of field vs accuracy)
• Battery saving mode

• Offline-first: Works without internet connection
• Installable: Add to home screen like a native app
• Fast: Cached for instant loading
• Mobile-optimized: Touch-friendly sliders and controls

• Node.js 18+
• npm or yarn

# Clone the repository
git clone https://github.com/yourusername/flash-distance-calculator.git
cd flash-distance-calculator

# Install dependencies
npm install

# Start development server
npm run dev

# Build for production
npm run build

# Preview production build
npm run preview

1. Fork this repository

2. Update vite.config.js:

   export default defineConfig({
     base: '/your-repository-name/', // Change this to your repo name
     // ... rest of config

3. Enable GitHub Pages:

   • Go to repository Settings → Pages
   • Source: "GitHub Actions"

4. Push to main branch:

   git add .
   git commit -m "Initial deployment"
   git push origin main

5. Access your app:

   • Your app will be available at: https://yourusername.github.io/your-repository-name/

1. Set your flash's Guide Number in settings
2. Choose your photography mode (Digital/Analog)
3. Set target distance with the slider
4. Select from suggested aperture/power combinations
5. Use the Quick Power Reference for at-a-glance power levels

• Guide Number: Enter your flash's GN (usually 30-60 for speedlights)
• Photography Mode:
  • Digital: ISO controls on main screen
  • Analog: Fixed ISO setting in preferences
• Available Apertures: Select which f-stops you use
• Distance Range: Set your typical shooting distances
• Priority Weights: Adjust recommendations (efficiency/DOF/accuracy)

The app uses the standard flash photography formula:

Distance = (Guide Number × √(ISO/100) × √(Power)) / Aperture

Unlike traditional flash calculators that require you to input power and aperture first, this app lets you:

1. Set your desired shooting distance
2. See all viable power/aperture combinations
3. Choose based on your priorities (battery life, depth of field, etc.)

• Optimal: Best overall recommendation
• Perfect: Low power + deep depth of field
• Efficient: Battery-saving power levels
• Max DOF: Highest f-numbers available
• Deep DOF: Good depth of field options

Dynamic table showing:

• Your configured apertures (rows)
• Your distance range (columns)
• Color-coded power level bars
• Real-time calculations based on current ISO and GN

• React 18 - UI framework
• Vite - Build tool
• Vite PWA Plugin - Service worker and manifest
• Tailwind CSS - Styling (CDN)
• Lucide React - Icons

• Service Worker: Caches app for offline use
• Web App Manifest: Installable with app icons
• Local Storage: Persistent settings
• Responsive Design: Works on all screen sizes

• Chrome/Edge 88+
• Firefox 85+
• Safari 14+
• Mobile browsers (iOS Safari, Chrome Mobile)

• Full functionality without internet
• Settings persist between sessions
• Calculations work entirely client-side
• Service worker caches all assets

• Large touch targets for sliders
• Mobile-friendly button sizes
• Swipe gestures supported
• No accidental zoom on inputs

1. Chrome/Edge: "Install" button in address bar
2. Safari: Share → Add to Home Screen
3. Android: "Add to Home Screen" prompt

• Install once, works forever offline
• No data usage after initial install
• Perfect for location shoots without internet

• Set distance (1-3m)
• Choose f/2.8-f/5.6 for shallow DOF
• Get optimal power levels for soft lighting

• Configure 2-6m distance range
• Use f/4-f/8 for group shots
• Battery saving mode for long events

• Wide aperture range (f/2.8-f/16)
• Multiple flash units (different GN values)
• Precision distance calculations

• Set film ISO once per roll
• Clean interface without digital clutter
• Focus on aperture and power decisions

• Initial release
• Distance-first calculator
• Digital/Analog photography modes
• PWA with offline support
• Quick Power Reference table
• Customizable settings

1. Fork the repository
2. Create a feature branch: git checkout -b feature-name
3. Commit changes: git commit -m 'Add feature'
4. Push to branch: git push origin feature-name
5. Submit a pull request

This project is licensed under the MIT License - see the LICENSE file for details.

• Flash photography community for feedback and testing
• Open source contributors
• PWA community for best practices

• Issues: GitHub Issues
• Feature Requests: Create an issue with the "enhancement" label
• Documentation: See this README and inline help

• Update repository name in vite.config.js
• Update URLs in index.html meta tags
• Test build locally: npm run build && npm run preview
• Check PWA features work in production build

• Enable GitHub Pages with "GitHub Actions" source
• Push to main branch
• Wait for Actions workflow to complete
• Test deployed app on mobile device
• Verify PWA installation works

• Test offline functionality
• Verify settings persistence
• Check on different devices/browsers
• Update README with actual deployment URL

Your app will be live at: https://yourusername.github.io/flash-distance-calculator/

Built with ❤️ for photographers who love the perfect exposure