Confused needs clarification on photography terms!

[tokrot]

Hi guys,

was confused by several terms. Need help to clarify here...

1) example: Lens aperture normally labelled as F2.8 - F3.1. But mine s602z aperture is from F2.8 to F11. How does we calculate the aperture from the F values written on the barrel ring?

2) What does mulitpler in DSLR mean? like the 1.5? Isnt it better?

Thanks..

 

[showtime]

1. firstly, there is no NORMAL way of labelling a lens. they are all different and have different appertures. if you see a range of appertures ie f2.8-4, this means that at the widest focal length, the max apperture f2.8 and at the most tele focal length, the max apperture is f4. for lenses which state only one f stop number, this means that the maximum apperture is that number through out the focal length

2. 1.5 multiplier means that your angle of view is equivalent to a focalllength 1.5 times that of the lens that you are actually using. for instance, it you are using a nikkor 12-24mm dx lens with a nikon dslr with 1.5 multiplier, the effective picture angle that you will get is equivalent to shooting with a 18-36mm lens on a 35mm film camera...(12x1.5=18, 24x1.5=36)