About Nikon 55-300mm VR Nikkor lens?

How much can a 55-300mm lens zoom? Up to how many times can it zoom? For ex.: 3x zoom, 5x zoom…

Nikon AF-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR Lens
Rs. 19550
A DX-format super-telephoto zoom lens with built-in vibration reduction for simple and enjoyable 5.5x super-telephoto shooting.
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You are now using a dSLR, so you can forget using any zoom range.

Here is why. I have a 12-24 mm wide angle zoom or a 2X. I also have a 200-400 mm telephoto lens also a 2x. As you can see the optical zoom range is not related to anything once you move from P&S cameras.

The 55-300 mm lens costs just under $400 and gives you a longer reach than the 55-200 mm lens.

Here is how to understand how those different focal lengths "see" the images.

http://imaging.nikon.com/...simulator/

If you want a single lens solution, the look at the 18-200 mm or 28-300 mm lenses

The "x" rating is simply a ratio of the longest to shortest focal length. So 300/55 = 5.4x

But realize, like Ace above that being a relative rating, there could be several combinations of lenses that have the same "zoom power".

Zoom power in a DSLR is useful for a couple of things.

First, know that super-zoom lenses tend to have marginal quality. So an 18-200mm lens (11.1x) would be known as a super-zoom, and sure enough, it does have some sharpness issues when compared to a more traditional SLR lens which vary anywhere between 1.5x and 3x.

The second reason is to evaluate different lenses.

For instance if you are considering buying a 18-270mm or a 28-300mm lens, the zoom power will help you decide. The difference between 270 and 300mm is insignificant (300/270 = 1.1) which means almost no discernible difference, and if you compare photos of the same object taken at 270mm and 300mm, you will see that this is so.

But then, if you compare the low end of 18 vs. 28 (28/18 = 1.5), then the 18mm lens will have a 50% more coverage at the low end.

In reality though, say you have a 55-200mm lens, and are consider buying a 55-300mm lens. Even at 50% (300/200 = 1.5), the difference will be noticeable, but not significant. In my view, I would not buy the 55-300mm lens if I already owned the 55-200mm lens as you will never need to use both.

My personal preference is to not worry about the different focal lengths until you have at least a 2x difference. So if you have a 88-200mm lens, I would not buy a longer lens unless it is a 400mm lens, as 400mm is a 2x difference 200mm (400/200 = 2).

The reason all of this is true is that optics behaves according to the Inverse Square Law, and you need a 2x change to see any significant difference, whether it be focal length, exposure, or any other value.