Having seen some excellent work done by Weihao Wang with this lens, I bought one recently. But I don't know the max operational/available aperture of this lens. Please tell me if you have known the answer, thanks.What's the max operational aperture of Sigma 180 2.8 APO Macro?
Having seen some excellent work done by Weihao Wang with this lens, I bought one recently. But I don't know the max operational/available aperture of this lens. Please tell me if you have known the answer, thanks.
Camera lenses state the max. aperture (photographic term. Not the actual diameter. Best named focal ratio) in their "full name"
Therefore, the Sigma 180mm f2.8 will have a maximum focal ratio of f/2.8
If you want the lineear aperture diameter you calculate: D = FL/f = 180/2.8 = 64mm
Therefore, the Sigma 180mm f2.8 will have a maximum focal ratio of f/2.8
If you want the lineear aperture diameter you calculate: D = FL/f = 180/2.8 = 64mm
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