The Download Now link directs you to the Apple iTunes Store, where you can continue the download process. You must have an active iTunes account to download the application. This download may not be available in some countries.
LensTutorial is a free app that allows to manipulate a photographic lens in a virtual environment. You can interactively slide focal length (zoom the lens), lens aperture and focusing distance. The app will show you how depth of field, angle of view and size of the model being photographed is changing according to your selection.
Lens Tutorial is providing ways to play with new zoom values to investigate photographic opportunities and see how lenses in different focal ranges behave in reality. Visual and interactive style simplifies learning for beginner photographers. Experienced photographers will find use for hard numbers that LensTutorial provides in a classic dof calculator fashion. Large font/hi-contrast mode will work well in studio or outdoor environments.