Nikon lens FX vs DX

[kenleyfred]

A few questions if I may for you more knowledgeable people.
As I mentioned a little while ago in the favourite lens thread, I will quite soon be getting my first DSLR. Have chosen the NikonD7000. That decision came after quite a few favourable comments here and some good links to read.

The lens to go with it is less easy.
The D7000 is DX format ( I'll be honest, have no idea what DX and FX means)
Does this mean it can only use DX lenses of which there seems to be a limited range when compared to FX.

My camera use will be general family shots,holiday, camping, trying to take wildlife photo's of whatever gets close to me.

In the DX I am looking at the AF-S VR11 18-200 Zoom and the AF 50mm F1.8.

In FX I'm looking at AF-S 28-300F3.5-5.6 ED VR Zoom and the AF 50mm F1.4.

Any comments please
Kenley

[dmdigital]

A DX lens is for the DX sensor (APS-C) cameras which have a smaller sensor than the FX which is equivalent to a full frame in 35mm.

On an FX camera a DX lens will cause the image to the sensor to be cropped to the DX size. On an DX camera either lens is fine to use. So in you case the answer is: "it doesn't matter".

Of the two lenses you mention the 28-300 would be the better choice as it is a better super zoom than the 18-200.

Either of the 50mm are good but the f/1.4 gives a softer look.

This might help: https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/23822/~/what-is-the-difference-between-fx-format-and-dx-format%3F

[33chinacars]

Not sure I quite aggre with dmdigital

Yes DX lenses are for Nikon APS-C / digital size sensors while FX lenses are for 35mm & full frame digital cameras.

DX af-s 18-200 (27-300 35mm equivelient )on a Nikon D7000 would be the prefered choice

The FX 28-300 is the equivelient on a 35mm camera, would be a 42-450 on a D7000. If you are going to use FX lenses on a D7000 their focal lenght must be multiplied by a factor of 1.5.

In most cases a DX lenses is better suited to DX size sensor.

Gary

[kenleyfred]

This is where I have been getting confused at various camera shops. Most have said variants of what is said above. One store said FX could not be used at all.
Am I safe to assume that they can be used but they will have a magnification of 1.5. And if so is this a good thing, more zoom, or a disadvantage. ie reduced performance or picture quality.

Thanks for advice. I'm nervous on potentially spending $1500 on the wrong lens.
Kenley

[Chucaro]

This is where I have been getting confused at various camera shops. Most have said variants of what is said above. One store said FX could not be used at all.
Am I safe to assume that they can be used but they will have a magnification of 1.5. And if so is this a good thing, more zoom, or a disadvantage. ie reduced performance or picture quality.

Thanks for advice. I'm nervous on potentially spending $1500 on the wrong lens.
Kenley

Careful, it is not a magnification, it is a crop factor which means that a 50mm lens on a DX camera will have a frame equivalent to a 75mm lens on a full frame camera.
This crop factor gives the avantaje on wild life, avian and flora photography that the subject fill the frame much better.
I use some old nikon lens (FX) on my D300s without any problem
If you are planning to use the lens for wild life the 28-300 have a better reach which is important and will be my choice to complement the 50mm f/1.4

[Chucaro]

The crop factor of digital SLR's by Fred Kamphues
(http://www.millhouse.nl/digitalcropfactorframe.html)

This is a better explanation that my one in spanglish :D

[33chinacars]

Yes I too use both FX & DX lenses on My D300 (DX size sensor) to great effect. My main lenses (95% of the time)is A DX Nikon 18-200. Some time I wish that I had bought the Tamron 18-270 for that little bit extra in focal length. When I need a longer lenses I use my old film (35mm) 400mm lenses which makes it a 600mm on my D300. Well thats the way I see it anyway.

Dont discount the Tamron 18-270 as it is a fine allround lenses.

So yes both film & Dx lenses can be uses on your D7000. But I believe you will get slightly better results with a dedicated Dx lenses. May not be noticable until you make very large enlargements.

Hope this helps

Gary

[dmdigital]

FX and DX lens Nikkor will all work on DX cameras (the lower end Nikon DSLR models may have issues with some of the earlier model AF lenses). Older 35mm film era Nikkor Lenses may not work on all bodies.

With the D7000 you have a DX sensor. This has a size of (W x H) 24mm x 16mm as apposed to the FX which is 36mm x 24mm. As you can see the FX sensor is 1.5x the DX sensor. As already pointed out this "crop factor", as it is often referred to, is often incorrectly used to imply a higher magnification. The reality is that the FX lens is built to a focused image falling on an FX sensor. When used on a DX sensor the sensor size means that the total focused image falls outside the size of the sensor leaving a smaller, cropped, portion of the image falling on the sensor. The first thought is "Hang on I'm loosing part of the image". But you don't as what you see in the viewfinder is what is captured. How can that be? It is because the cropped outer portion of the image falls outside of the mirror box of the camera and so is discarded. This is just like the circular parts of the image that the lenses sees that don't appear because the film or sensor of the camera is rectangular.

A DX lens is designed for the DX sensor, so it is optimised to create a circular image that will fall over a 24mm x 16mm sensor. Thus when shown an FX sensor it isn't producing a large enough image the point it appears to the sensor that will cover the entire sensor.

When people refer to an FX lenses being a different focal length on a DX camera what is really happening is that the image on the DX sensor has a better pixel density than the same cropped region of the FX sensor.
e.g The D3s (FX) and the D300s (DX) both take an image of slightly more than 12 megapixels. But the cropped (DX) region of the D3s is only 5.3 megapixels.

For a good reference on using the D7000 and on Nikon DSLR in general get hold of Thom Hogan's guide e-book: Complete Guide to the Nikon D7000 (http://www.bythom.com/nikond7000guide.htm)

[greg-g]

Most points are well covered above, but no one has mentioned size and cost.
As an FX sensor is 1.5 times larger than a DX, FX lens will general also have to be larger and hence heavier than its DX counterpart. FX lens are generally also more expensive.
My every day lens on my D90 (An older camera equivalent to the D7000) is the 18 - 200 zoom. My other lens are all FX, but only because they are older and purchased second hand.
Today I wouldn't bother to replace my 50mm f1.4 as the additional speed isn't generally required and the 50mm f1.8 is an excellent lens at half the price. My next lens will be a 35mm F1.8 that I think will be very handy and is well worth looking at.
The only real reason to purchase FX lens is if there isn't an equivalent DX, or if you are ever contemplating upgrading to a full frame FX camera. There are also often good second hand D series lens (Older lens for film and FX cameras) available on ebay. These work well on the D7000 as it has an internal focusing motor where the less expensive DX cameras don't.