Composition finder for plein air artist, urban sketch artist, & photographers. Size of a Credit Card - compact lightweightdesign fits in any wallet, camera bag or portable art kit Find the perfect proportion finder for any composition. Great Outdoor Activity for Kids; No More Screen Time. Golden Ratio / Fibonacci Rule / Fibonacci Sequence / Golden Mean / Golden Spiral / Golden Section Finder An American owned & operated company. The original Fibonacci viewer. This Golden Ratio/Fibonacci viewer is one of the best tools to help any artist compose their image. Whether you're a photographer, sketch artist, or plein air painter, use this viewfinder to find your composition before you press the button or commit paint to canvas. The Golden Ratio (aka the Fibonacci Rule) has been around since the 1200's and is a proven way to create the perfect proportion in your compositions. These viewers can be used as a great low tech activity by encouraging kids and adults to look for the Golden Ratio in their surroundings and out in nature. What a wonderful way to reduce screen time. The Golden Rule/Fibonacci pattern is etched into these crystal clear, 2mm, acrylic cards so they're completely waterproof and nearly unbreakable. They're also the size of a credit card (85.6 mm X 53.98 mm) making it easy to keep in any wallet, camera bag or plein air painting kit for all of you urban sketch artist. Want a place to keep all of your viewers and SD cards in one place? Add a wallet, also available separately. They make for great gift or stocking stuffers too!