SpyderLensCal provides a fast, reliable method of measuring the focus performance on your camera and lens combinations. It allows photographers to obtain razor sharp focusing or check to see that their lenses are working at their peak performance. This device is compact, lightweight and durable, with integrated level and tripod mount.
The problem Photographers have enjoyed the benefit of autofocus for 25 years now, but many still struggle with its accuracy and repeatability.
The solution Many newer DSLR cameras now offer a method to correct this issue: they allow you to store auto-focus correction data for several of your most important lenses