This year, I became convinced by both experience and research that it’s time to upgrade from Nikon’s DX format to a full-frame FX DSLR. However, I didn’t pull in enough income from freelance sales this year to finance the jump, so instead made some purchases to prepare for it–mostly lenses.

For those unfamiliar, DX is Nikon’s first digital sensor format, which has the effect of increasing all of your lenses’ focal lengths by 50%. Click here for a more complete explanation of why this happens. That might sound great at first–your 80-200mm zoom is now a 120-400mm zoom! But I hadn’t done my homework when I bought my first DX format camera (a Nikon D70s), and was disappointed to learn that my trusty wide-angle 24mm f2.8 Nikkor was now effectively a 36mm standard range lens. And I just can’t work without a nice, fast wide angle. This is why most kit lenses that ship with consumer level DLSRs are in the neighborhood of 17-55mm or 18-70mm. They’d be a superwide on a standard format sensor, but are just normal wide on a DX camera. However, many of those lenses are made exclusively for the DX format–slap them on a standard format film camera and there’s massive vignetting around the corners of the image–beyond the edges of what the DX sensor would cover.

Aside from magnifying focal length, the DX format also messes with one of my top priorities: low-light capability. It’s a basic fact of photography: Increased focal length requires increased shutter speed to freeze camera shake. That means no more bracing against a wall and shooting at 1/30 or 1/15 hand-held. Even shots at good ‘ol 1/125 can get jiggly when I’m using my trusty 50mm f1.8 wide open for low light scenes like candlelight vigils. Newer stabilized or vibration reduction (VR) lenses help to cope with this, but only help to freeze the camera–not the subject.

So for these and other reasons, Ken Rockwell has me convinced that FX is the way to go–both for sharpness and for that boogeyman of high ISO digital shooting: noise. The D700 has the mind-blowing available ISO of 25,600, but more importantly, according to Ken: “if you want to shoot in available light, ISO 6,400 looks great without excuses on the D700 or D3, but not on any DX camera.”

This becomes especially important when my microstock sites reject photos for too much noise, forcing me to abandon higher ISOs on my current D90. So here are the lenses that I invested in in anticipation of the Nikon D700 that I plan to purchase in 2010, all purchased used on eBay:

17-35mm f/2.8 ($1200)
28-200mm f/3.5 – 5.6G ($285)
70-300mm VR f/4.5-5.6G ($450)

As mentioned, I already own a 50mm f/1.8, and routinely use an 85mm f/1.8 and 80-200mm f/2.8 which are owned by Sojourners, though I’m trying to build up my personal kit. Granted, these together cost more than a used D700 body ($1900 or so on eBay), but without the lenses to use it effectively, it seemed better to put these horses before the cart. I also figure the longer I wait, the more prices on used D700 bodies will come down, while lens prices are relatively stable. I also jumped on some SanDisk rebate deals to stock up on 16GB CompactFlash cards, since the FX cameras all use those instead of the SD cards I currently use in my D90.

You may have noticed that most of the links above go to KenRockwell.com, which was an extremely valuable resource in researching lenses. I recommend hime for his encyclopedic listings of Nikon cameras and lenses, including discontinued models that may be just what you need. This is especially true in hunting down FX-compatable lenses (aka 35mm film lenses!) and separating the deals from the duds among Nikon’s catalog (like skipping the otherwise tempting 24-120mm VR).

To be honest, I’m still a little shocked at how much I’ve spent on this pile of lenses. But part of it is due to relative success in my first year of microstock, and the other part is justified by a need to make some longer-term investments in gear for reasons I will detail in a future post…. I’ll also likely write about my rationale for buying a new Lenovo T400 laptop that arrived at the office two hours after I left for the holiday break….