quick lens comparison question

[lazysnowdog]

i bought the Letus Extreme for use with my HVX200a. The "kit" i got came with a 50mm Canon 1:1.8. I'm looking at a 1.2, but am curious as to how much of a difference i can expect in having more light...any ideas on this??? Thanks in advance for the help, and happy thanksgiving!

 

[Huy Vu]

f1.2 to f1.8 is about one stop so in theory it's about twice as bright. However no lense that I know, including the Canon, performs well wide open at f1.2. Sharpness will suffer as well as a bokeh rendition. Never plan on buying faster lens as a means to avoid getting more light in.

 

[Admir]

The main reason why you should buy lenses with lower f-stop than the usual (f1.8) is that they will be a bit sharper when stoped down a few stops, a 50mm f1.4 will be sharper at f1.8 than a 50mm f1.8 at 1.8 (wide open) .