Dallmeyer Serrac 4” (100mm) lens head f/4.5 609549
Has an easily removed optical flat on the front which has ensured the front lens is in wonderful condition. The rear group has some coating wear, but generally the glass is clean. The barrel has some wear (see photos). Iris stops down to f/32. Comes in 32mm screw-thread mount and has an adapter ring to a fine thread of about 35mm diameter.
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