Durst Neonon 50/2.8 [Pentax V1]

AKA Agfa Magnolar enlarger lens. Made in Japan (Pentax?). Version 1 has a three-row stippled rubber aperture ring that functions as a stepless aperture ‘clutch. Serials (all 5xxxxx) engraved on fascia.

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Dimensions	50 mm
Focal Length (mm)	50
Max Aperture (f)	2.8
Min Aperture (f)	22
Aperture Blades	8 (Straight)
Elements	6 / 4
Rear Mount	M39
Production	1978-c.1985
Serial Numbers	510473, 520755, 527763, 537072