The DX/FX Combo Kit

Since the arrival of the D500 I’m seeing more and more folk opting for DX and FX combo kits. In other words, one of their bodies is FX, the other is DX. Sometimes it’s D810 and D500, sometimes it’s D750 and D7200, occasionally we get something more dramatically "mixed."

I’ll be right up front and say that I don’t like traveling with mismatched sensor sizes. Why? Because it adds a layer of thought to what I’m doing and why. Worse still—unless the two bodies are specifically a D5 and D500—you’re going to have control, button, and UI dissonances as you switch back and forth between bodies, and you just can’t set up the DX and FX body exactly the same. 

One of the things that motivates this DX/FX combo practice is the notion of getting “the most out of any situation.” By most, we mean one stop, basically. One stop better noise handling or dynamic range (all else equal), one stop better DOF (all else equal), or one stop better DOF isolation (all else equal). 

Ten years ago, I would have killed for another stop in dynamic range. Today, not so much. It’s a rare situation where I feel that I’m in need of more dynamic range, and the situations where I tend to want it—landscapes mostly—there’s always exposure stacking (HDR). If I’m truly shooting in low light—outdoor sports at night, for instance—I’ll just bring my 4 and D5. No, I’m not tempted by the D500 in that instance, as one stop is just pushing too far under bad lighting when you’re trying to keep shutter speeds above 1/1000. 

Note: this is not to say that the D500 is terrible for night sports under the lights, it’s just not optimal. Why would I want to shoot with one optimal and one non-optimal body? 

Then there’s the lens issues. Back when the D3/D300 appeared, I often used the 12-24mm f/4 DX on both bodies. It covered at a real 18-24mm on the D3, and it was obviously a good 18-36mm effective on the D300. With 12mp sensors, the 12-24mm tended to look just fine. 

But these days, the high pixel densities we’re pushing (20-24mp DX, 20-36mp FX) definitely start to show the limits of many lenses, so the lens compromises I was using just don’t play well any more. And what that means is, at a minimum you’ll be carrying an extra lens (wide angle DX zoom, likely; the variable field curvature of the 14-24mm doesn’t make it a great candidate for DX use, and it’s hard enough to get it dialed in right with FX).  

So I tend to see a lot of folks trying to carry a kit something like this:

  • D500 body
  • D810 body
  • 11-20mm f/2.8 Tokina (DX)
  • 16-35mm f/4 Nikkor
  • 24-120mm f/4 Nikkor
  • 70-200mm f/2.8 or f/4 Nikkor

That doesn’t do it for me. Too much compromise all around. A better choice is:

  • D500 body
  • D810 body
  • 11-16mm f/2.8 Tokina (DX)
  • 16-80mm f/2.8-4 Nikkor (DX)
  • 14-24mm f/2.8 Nikkor
  • 24-70mm f/2.8 Nikkor
  • 70-200mm f/2.8 Nikkor

That’s as little compromise as I can put into a DX/FX combo kit right now. Well, okay, if we want to sub in a lot of f/1.4 or f/1.8 FX primes in the mid-range, we can really push ourselves in low light (with the FX body ;~). 

As usual I’ll be taking August off this year and spending the month shooting full time. I’ve decided to just take a DX kit with me. For a lot of reasons, really, but the primary one being I’m not too worried about low light work, and I can make a pretty reasonable DX kit that won’t weigh me down these days (though where modern DX wide angle zooms and primes are, I have no idea [buzz buzz]). 

Since I’ll be doing a lot of wildlife shooting, my kit will likely be:

  • D500 body
  • D7200 body
  • 10.5mm f/2.8 Nikkor
  • 16-80mm f/2.8-4 Nikkor
  • 70-200mm f/2.8 Nikkor
  • 300mm f/4 Nikkor
  • and either the 80-400mm or 200-500mm Nikkor for the big reach (I really want to try the new 400mm f/2.8, but that makes the kit a bit on the heavy side for what I need)

I’ll have to live with the button/control/ergonomic differences, though I can program controls around a few of those. I’ll live with giving up one stop of DOF isolation and potential high ISO. But because I’ll be DX only I won’t be thinking about crop factors or perspective changes or DOF changes as I switch bodies. From an image quality standpoint, the D500 and D7200 are so close to one another that I won’t even be thinking about that. 

And that brings me to my point: are you always thinking about gear, or are you always thinking about pictures? Yes, choosing just DX or just FX puts some minor limits on the pictures I might be able to accomplish, but I just file the limits I’m working with in my brain and shoot. I don’t think about how I’m going to break those limits by switching bodies (and maybe lenses, and who knows what else). I think about the pictures I can take right now. 

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