what is the meaning of "Nikon AF 28-200mm f/3.5-5.6 G IF ED?"

[marissawu]

i like to see some gears on the internet,including lenses but i do not understand why some lenses are named like this or like that .so,i found a lens,it's "Nikon AF 28-200mm f/3.5-5.6 G IF ED" and i am curious what it means.needing your help people..thanks

p.s: perhaps sample images will help me to understand more

[inkista]

Nikkor means it's a Nikon lens.

AF means it autofocuses on bodies that can do that. With digital SLRs, it means that it will only autofocus on bodies that have a focus motor built in (i.e., not on the D40/D60/D3000/D5000).

28-200mm is the focal length--its zoom in quantitative terms. It's a wide angle to telephoto on full-frame, a widish to very telephoto on a crop body.

f/3.5-5.6 is its maximum aperture(s) at the ends of the zoom range, so at 28mm, the widest the aperture can be set is f/3.5, and at 200mm, the widest it can be set is f/5.6.

G means it's a G-mount lens, and has no aperture ring.

IF means it doesn't change its length as you focus it.

ED means Extra-low Dispersion glass was used in the lens to control chromatic aberration.

Nikon's website has a glossary where you can look up most of this stuff, and I'd recommend looking at this lens primer to learn the basics of lenses.

[Almond.Butterscotch]

inkista nailed it.

AF variations include AI, AI-S, AF, AF-D, AF-S (and some others that are too rare to mention). All AI-S are AI plus some (both are always manual focus); AF is AI-S plus autofocus; AF-D is AF plus digital bonuses, AF-S is AF-D but uses electrical contacts instead of a screw to autofocus. AF-G is AF-S without the aperture ring (unless I'm mistaken the two are mutually exclusive to each other).

28-200 is 28-200 on a full-frame/FX camera and 42-300mm** on a DX body.

IF is a plus in lenses- fewer externally moving parts makes it harder for 'stuff' to get into your lens.

ED means better quality.

**EFFECTIVE

[dakwegmo]

Originally Posted by Almond.Butterscotch

28-200 is 28-200 on a full-frame/FX camera and 42-300mm on a DX body.

This is incorrect. The focal length is constant regardless of the body it is placed on. The amount of the image circle used changes depending on the size of the sensor, but the focal length does not.

[vandergus]

Originally Posted by Almond.Butterscotch

inkista nailed it.

AF variations include AI, AI-S, AF, AF-D, AF-S (and some others that are too rare to mention). All AI-S are AI plus some (both are always manual focus); AF is AI-S plus autofocus; AF-D is AF plus digital bonuses, AF-S is AF-D but uses electrical contacts instead of a screw to autofocus. AF-G is AF-S without the aperture ring (unless I'm mistaken the two are mutually exclusive to each other).

28-200 is 28-200 on a full-frame/FX camera and 42-300mm on a DX body.

IF is a plus in lenses- fewer externally moving parts makes it harder for 'stuff' to get into your lens.

ED means better quality.

The D in AF-D actually stands for distance not digital. It means that the lens sends information about the focus distance back to the camera so it can make smarter decisions about metering (mostly TTL flash metering). Not terribly important. And G lenses are not necessarily AF-S. The lens in this post, for example, is a G lens but not AF-S. And while I'm at it I'll be picky and say that the lens is still a 28-200mm lens on a DX body, but it is has a field of view equivalent to a 43-300mm lens mounted on a FX body. Sounds like a silly correction but I'm hoping it will prevent lot's of future misunderstandings.

[OsmosisStudios]

Originally Posted by dakwegmo

This is incorrect. The focal length is constant regardless of the body it is placed on. The amount of the image circle used changes depending on the size of the sensor, but the focal length does not.

A fair point, however, most writings consider the DX crop factor and will write it as 28-200 FX and 42-300 DX