Sony's groundbreaking RX10 won our award for the [http://www.imaging-resource.com/news/2013/12/11/cameras-of-the-year-2013-best-pocket-ilc-bridge-travel-zoom-cameras#best-enth-zoom](best enthusiast zoom of 2013). It's lightning fast performance, bright, f/2.8 lens, 24mm to 200mm zoom range and solid video performance led us to conclude that it "offered something truly unique." While the RX10 still stands alone in some respects, we can no longer call it truly unique, thanks to Panasonic's tremendous FZ1000, a worthy adversary where none existed before. This is probably the toughest matchup that we've yet judged, but we were able to condense our findings to one winner (for most photographers).
First things first: it should be noted that while these two cameras are each others' nearest competitors, they differ in several key ways. The first is the lens. The FZ1000 gives doubles the max telephoto of the RX10, while keeping the wide-angle range nearly identical (25mm vs 24mm). The tradeoff is you lose the constant aperture f/2.8 of the RX10; the FZ1000 jumps to f/4.0 by 135mm.
The FZ1000 is a larger and heavier camera overall, but the size of the RX10 puts it so far outside the range of 'compact camera' that we don't find this to be a significant differentiator. While Sony has made varying claims about the degree of weather sealing, it's current claim of 'dust and moisture-resistant' is sufficiently vague to eliminate it from consideration. The RX10 build quality is significantly better than the FZ1000: Panasonic fans can think of the difference as comparing a GH4 to an FZ200.
Both provide image stabilization: optical on the RX10, sensor-based on the FZ1000. We found the performances to be fairly simiar @TODO update.
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Panasonic provides more framerate and resolution pairs and even supports slow motion recording, which are nice additions. While the FZ1000's addition of 4K left us droolling, we were dissapointed by a two omissions. The first was the Panasonic skipping an integrated neutral density filter like the RX10's. Still photographers shrugged at this omission, but anyone who's done even a little bit of video will be dissapointed here: you'll have to screw your ND filters onto the lens. The second big dissapointment was the omission of a headphone jack.
While Sony is no slouch in the video department, Panasonic somehow managed to best it in two recent cameras. The Sony A7S features the best low light video we've ever seen, but can't record 4K video without an external recorder; Panasonic's GH4 manages this feat without breaking a sweat (for $800 less). Whatever secret sauce Panasonic has in its R&D facilities, the FZ1000 appears to have enjoyed a heaping helping of it, because the FZ1000 is the first camera to ever provide this feature for less than $1,000. And that price brings us to...
If the RX10 was avaiable for $1000 this would be a torturous decision. The RX10 is a gem: it's superb build quality, beautiful, fast lens and fantastic handling make it one of our favorite cameras of 2013. There are tradeoffs in either direction. To be sure, there are photographers who will be happier with the RX10. If the practical advantages of a fast, constant aperture lens, headphone jack, integrated ND filter and stellar build quality are what you're after, pick up the RX10 (but perhaps not before waiting to see if Sony sees fit to cut the price of the RX10...). On the other hand, if it's zoom that you want and you're in love with the idea of 4K, the FZ1000 is your ticket.
But this isn't a difficult fight to call for most photographers. The $400 premium Sony asks for the RX10 is really the deciding factor. When one camera is 50% more expensive than it's closest competitor it had better offer something special. The RX10, while incredible, just doesn't offer enough additional functionality to sway our decision. For most photographers the decision is easy: pick up the FZ1000. Panasonic has a second hit on its hands this year and we couldn't be happier to see such success.
With Sony's breakneck development and fat product pipeline (witness the A7S follow-up to the A7/R, the RX100 III and the A6000), you can be sure Sony's been working on the RX10 successor since before the release of the RX10. Perhaps the most interesting comparison will be the FZ1000 and whatever Sony has in its labs...
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