This particular lens has a 0.14 magnification ratio. The aperture of the lens is maximum ƒ/1.7 and minimum ƒ/22.
From London Camera Exchange
Panasonic Lumix G 25mm F1.7 ASPH Silver (H-H025E-S)
Camera Centre
Panasonic 25mm f1.7 Lumix G ASPH Micro Four Thirds Lens - Black
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