hello boys and girls!
i have these questions which had been burning me up since last night!
1. wide-angle prime lenses!
i understand prime lenses when wide open at biggest apertures tend to have a relatively small area of focus compared with the rest of the image ie. background all oof. i thought when using wide-angle lenses, you want to take it all in with everything in sharp focus and doesnt that mean having to stop down to achieve overall sharpness for the whole image? that defeats the purpose of having a big aperture in the first place isnt it?
2. macro / zoom / tele lenses!
let's consider the 70-300 lenses from both canon and sigma. the sigma lenses states clearly it is capable of macro shots but the canon doesnt. can the canon lenses take good macro shots? in the case of the sigma, what is its primary function - a zoom, a tele and then to throw into the mix, a macro lens? what is this ratio thing for macro lenses, 1:1, 1:2, etc.?