[viovanda]

http://fstoppers.com/can-you-tell-the-difference-between-a-100-lens-and-a-1600-lens 不計較散景的話1.8 sharp d ,但其實大家好明白人像鏡散景先糸最重要

[siusiusiusun]

1.8 1.2 我都有, 但我愛用支1.2 多D

[chiuwater]

如果我無睇錯50 1.2影出到個satuation好似偏低,主體比較flat,但係點解同一光圈(f2),50 1.2散景咁出,同一焦距同一光圈,理論上景深範圈唔係相同架咩

[h0001244]

<<<同一焦距同一光圈,理論上景深範圈唔係相同架咩>>>

That's theoretical only, due to lens construction in real practice 50.2 tends to produce more blur in out of focus area. In areas that just a bit out of focal plane, 50.8 tends to give a sharper image, that's why the overall output gives a false perception to readers that it is way sharper than 50.2. But it fact, it cannot blur the out of focus area perfectly like 50.2