Complex sentence: It was noteworthy for being the first digital SLR for a 35mm lens system to have an imaging chip the full size of a 135 film frame--all previous ones had a sensor smaller than that giving a cropped view (see magnification factor).
Split into simpler sentences: It was noteworthy for being the first full frame digital SLR--a camera for a 35mm lens system that has an imaging chip the full size of a 135 film frame. All previous dSLRs had a sensor smaller than that giving a cropped view (see magnification factor).