Lens barrel with iris diaphragm calibrated 1-5. Four elements 15/25/35/45 in five normal, five wide angled and four landscape combination. Emil Busch. Busch Combination Lens Aplanat Series I
Busch Wideangle Aplanat lens No 4. Series C f16 10in. Rotating aperture plate with f16,22, 32,45,64,88. Busch Wideangle Aplanat Lens No 4
Busch's portrait aplanat No.2 lens F.8 with 7 inch f.l. with a ring type iris diaphragm. c.1910. Busch's portrait aplanat No.2 lens circa 1910