Moving up to FX Lenses

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With the D800 expected soon, many people will be buying their first FX camera. There are many advantages (and some disadvantages) in moving to FX from DX. Perhaps the biggest change for most current DX owners will be upgrading lenses.

While the D800 will be full-frame format and can use any FX and DX lenses produced over the past 50 years, many will want the advanced features offered in the latest FX glass, including AF (autofocus) and VR (vibration-reduction), or in faster glass (wider apertures).

Current DX lenses are relatively inexpensive compared with new FX lenses. One reason for this is the size of the actual glass lenses required. The FX sensor is physically larger than the DX sensor. The outer lens elements must be larger to create a larger image circle.

Another reason is demand. There are many more DX format cameras sold than FX. DX lenses are made in much larger quantities and the economy of scale allows a lower cost.

Full-frame lens customers tend to be professionals who demand high durability and the best image quality. This often means using more durable, impact-resistant materials. In addition, the image quality they demand requires use of precision glass elements. They also have tough demands for low-light use and the ability to freeze action with fast shutter speeds. All this means the glass has to be even larger to gather more light. Big glass requires yet more material and precision, and drives up the price.

The end result is that FX lenses cost more than DX. The cost difference can sometimes be several times higher. For example, a tele-zoom: the DX 55-300mm VR sells for $360 while the FX 70-300mm VR sells for $525. But if you want faster glass, the 70-200mm f/2.8 VR II is $2,200. Prime lenses also share this difference: The 35mm f/1.8 DX currently sells for $200, while a slightly faster FX version 35mm f/1.4 sells for over $1,600. (One might note however that a 35mm FX lens will act like a 50mm on a DX camera, so you could get a similar result on FX using a less-expensive 50mm FX lens.)

The the cost in mind, here are some example lenses to take advantage of your new Nikon D800 camera. A wish list of sorts:

  • Ultra Wide Zoom: 16-35mm f/4 VR $1,150
  • Wide Prime: 24mm f/1.4 $2,000
  • Normal Prime: 50mm f/1.4 AF-S $450
  • Portrait Prime: 85mm f/1.4 AF-S G $1,700
  • Do-it-all: 28-300mm VR $900