I series | A new photographic experience, "Premium Compact Primes" for mirrorless usersThe Sigma I series features full-frame-compatible lenses that offer mirrorless users a new and better alternative, both in the experience of shooting with the lens and in the impressive results it is able to achieve.One of the key advantages of mirrorless cameras is their smaller form-factor, and this new 35mm optic is designed to be perfectly matched to these more compact systems without sacrificing performance. This combination of superb optical quality with exceptional portability, not previously possible with Dslr systems, will bring new opportunities to this and future generations of photographers.Simultaneously, Sigma is aware that, in this day and age when we have such huge diversity when it comes to what we use to photograph, as represented by smartphones, people look for something more than a mere act of "taking pictures" when they choose to own a camera and lenses.