Lens Confusion - Dx/Fx formats. (Buying new lens)

[Jasmeet]

Hi,

I have a Nikon D5000. First of all, am I right in thinking that it is a Dx format camera? And what are Dx and Fx formats?

Second question: I am going to buy a 55-200mm for my camera. There are two Nikkon Models - AF-S DX VR Zoom-Nikkor 55-200mm f/4-5.6G IF-ED (3.6x) [Fx Format] and AF-S DX Zoom-Nikkor 55-200mm f/4-5.6G ED [Dx format] that I found on their website. According to this link NIKKOR Lineup | Nikon , both lenses are marked as Dx format. But, as I click on AF-S DX VR Zoom-Nikkor 55-200mm f/4-5.6G IF-ED (3.6x) | Nikon , it says its an FX format.

Firstly, what is the difference between Dx and Fx in cameras and lenses and are they fully compatible with each other?
Secondly, what's the difference between these two lenses? Which one should I buy for my Nikon D5000?
And, just in case anyone's bought something from Dubai, which is the best place in Dubai for the above gear?

I would really appreciate any help as I'd be going in 2-3 days.

[Shokinen]

Hi Jasmeet,

Some people here can explain it every well technically but I will try summerize it in "normal" words. Think about you lens as a circle showing an image. Now think about your camera as a rectangle that fits perfectly in that circle and is only taking that protion of the image.

Keep that in mind while we focus a few seconds on the sensor size. Your D5000 has what we call a crop sensor. Full Frame sensor are the same size of a film we used to have in our camera (35mm). Crop sensor are smaller. So if we get back on the circle analogy, the Full Frame rectangle would touch the edge of the circle. The crop sensor (your camera) take a smaller portion because the rectangle is smaller.

Now that you know the theory, what is the difference between DX and FX lens ? DX lens are designed for smaller sensor meaning the circle is not super sharp up to the edges. There is no need because your rectangle is smaller. FX lens are sharp up to the edges of the circle because the rectangle is bigger.

Can you used FX lens with your D5000 ? Of course ! and if you ever upgrade to a Full Frame camera, you'll be able to use it's full potiential (if you use a DX on a Full Frame you have to set your camera or to use a smaller portion of the sensor which defeat the purpose). Some lens like the 70-300 are only FX, there is not DX alternative.

I currently own 2 DX lens and 1 FX and I wouldn't be able to tell you which one is what if it wasn't for the DX sign on the lens.

Hope this help

[Aegea]

To add a little more detail, the FX sensor is about 36x24mm. DX sensor is about 24x16mm.

The 55-200 is a DX lens, I can't see where it says or implies FX on the page you reference. In fact, if you look at the MTF charts on that page, the sharpness starts to fall apart at about 12mm, so the lens can't effectively cover much more than a 24mm diameter circle, i.e., DX sensor. I believe the difference between the two models is that one has VR and one doesn't. VR stabilizes the image so you can use slower shutter speeds without camera shake blurring the result.

[Jasmeet]

Thanks Shokinen,
That means both the lenses which I mentioned are DX format? And then what's the difference between both of them? What am I better off with?

[Jasmeet]

@ Aegea, Thanks, helpful.

AF-S DX VR Zoom-Nikkor 55-200mm f/4-5.6G IF-ED (3.6x) | Nikon

Look at the left of the image of that man with snow on his face. It says FX format.

[zona5101]

Both of those are DX lenses , one has the vibration reduction the other doesn't. For your D5000 you need to ensure the lens you choose has a built in focus motor. In the nikon lens line-up chart it is the coulm "swm". In the case of the two lenses you are considering, both have internal motors and will work fine with your camera.

Camera Lenses from Nikon

[OsmosisStudios]

Here's the long and short of it.

You have a D5000, which is a DX camera. That means you can use both FX and DX lenses.
If you have a full frame camera (as of now, the D700, D3, D3s and D3x), then you can only use FX lenses*

*You can use DX lenses, but with severe useability issues that dont make it viable.

[Shokinen]

Originally Posted by Jasmeet

Thanks Shokinen,
That means both the lenses which I mentioned are DX format? And then what's the difference between both of them? What am I better off with?

Yes they are both DX and the only difference is the VR.
At 200mm, you'll see that everything seems is shaking more than at 18mm. VR really shine with longuer focal lenght so I recommend to go with it. It's definitely worth the extra.

As for the Nikon website, this is a mistake. I use the Canadian site (faster and I like the way they classed the lens better) and you'll see that they are both in the DX section. Plus, as Aegea said, the MTF proves it.

http://www.nikon.ca/en/Lens.aspx

[Aegea]

@Jasmeet - you're right, I hadn't noticed that "FX Format". I think that's just wrong.

[Jasmeet]

Oh, thats a 100 dollars more expensive.. and i still have to consider the currency exchange charges.. but i guess, i'll still go for the VR..
Thanks for all your help.. Shokinen, osmosis, aegea, zona..