nikon lens 70-300mm- ED,

[siva_ethir]

HI: all

In the above lens, if it is written like this "Nikon ED AF Nikkor 70-

300mm f1:4-5.6 D" What does it means by f1:4-5.6 D. it is confusing

me. What is the minimum aperture of this lens. pls help me out. I

bought this lens as used one to use on my nikon d 70s as telephoto

lens.Is it ok for my need?

thanks

siva

[peter_nikodem]

at 70mm it is 4

at 300 it is 5.6

[steve_dawson1]

The maximum aperture (smallest f number) varies according to focal length. As Peter said it is f4 at 70mm and f5.6 at 300mm. If you search photo.net you will see that a number of people have posted that this lens is pretty good for its price, size and weight. And it works fine with the D70s.

[siva_ethir]

Thanks for all for the answer and the time spent on my request.

thanks

siva

[yeux tortu]

The D means that the lens will tell your D70 the distance of the subject to the focal plane of the sensor, which in turn improves your exposure metering ("3D matrix metering")according to Nikon marketing.

 

It should be okay for your needs, for best results, in my experience, stay away from 300mm and stop down to F8. Google "Thom Hogan" and "Ken Rockwell" for two opposite opinions about this lens.

[lex_jenkins]

That's called a variable aperture zoom. As other folks have noted, the lens is "faster" (larger maximum aperture) toward the short end and a bit "slower" (smaller maximum aperture) toward the long end. This applies whether it's a telephoto zoom such as yours, a midrange zoom (typically something like my 28-85mm AF-Nikkor) or a wide angle zoom such as Nikon's less expensive 17-35mm lens (not the f/2.8 version). All have variable apertures.

 

This design allows lens makers to provide lenses of good quality that are more affordable than faster non-variable aperture zooms. It's a tradeoff and usually a pretty reasonable one.

 

Other lenses may also vary in maximum aperture, but this isn't noted in the nomenclature of the lens. For example, some macro lens designs are such that when the lens is at maximum magnification the effective maximum aperture decreases. This is sometimes referred to as the "bellows effect" because the same thing happens when using a bellows for macrophotography, altho' I'm not sure the term is really self descriptive. My older 55mm f/3.5 AI'd Micro-Nikkor starts out at f/3.5 at infinity focus but decreases in speed toward minimum focus/maximum magnification.

 

Some lenses are designed to avoid this effect, but there may be other tradeoffs, such as a change in effective focal length, even tho' it's a prime lens.

 

Don't worry about any of this for most purposes. Your camera's TTL metering will automagically compensate for these variations. So will dedicated flash with the later model autofocus lenses. It may be necessary to manually determine the actual aperture when using non-dedicated flash whether on the hotshoe or monolights.

[juan_su]

Is it ok for my need?

 

To answer this questions, we need to know what your needs are? Franckly, it doesn't really matter what any one else thinks about this. Only you can really know if it is enough for your needs, if you find that it is not, then let us know how it isn't meeting your needs and we can assist. Happy ShootinG!