The 10" that covers 7x17 is the Wide Field Ektar, which is either a biogon type or double-gauss type design. The 10" Commercial Ektar is a Tessar, and barely covers 8x10. It is really a 5x7 lens. The 12" Commercial Ektar and 14" Commercial Ektar do cover 8x10 with movements. The 14" Commercial Ektar will cover 11x14 with limited movement.