i am reading this: http://en.wikipedia.org/wiki/Aperture
and i have a few questions...
the article states that "The photography term "one f-stop" refers to a factor of √2 (approx. 1.41) change in f-number, which in turn corresponds to a factor of 2 change in light intensity." and states that there are got f1.4 f2 f2.8 f4 f5.6 f8...
Q1. (dslr) which means when we up 1 stop f2 becomes f2.8? correct?
Q2. (dslr) my nikkor len is f3.5 - f5.6, how come the f3.5 is not anywhere on that scale? there is only f2.8 and the next stop is f4, how does f3.5 comes in?
Q3. (pns) there are 2 f stop, one is on the len, Maximum aperture f/2.8 - f/3.5, but on my pns camera, the f appears from f3.2 - f8... how come got this difference? and which one is accurate? does that means anything from f3.5 onwards, it is non existence for that camrea?
Q4. (pns) Focal length 5.8 - 58 mm (35 mm equivalent: 38 - 380mm). So for this PnS, do i need to multiply the crop factor to get the actual mm? or 38 is already factor in the crop factor?