I'm in the process of simplifying my camera bag. As part of this, I'm strongly considering purchasing either the Sigma Merrill DP1 or the Ricoh GR. These two digital cameras are very similar, yet very different.
You may be asking, why not the Nikon A? Why not the Sony RX1R? Why not the Fuji X100s? Well, because of economics and value. Those three cameras are all very fine cameras, but none of them (not even the Sony) are so much better for what I'm specifically looking for that they justify the higher cost.
Better questions would be, why the Sigma Merrill DP1? Why the Ricoh GR? I like the idea of a fixed focal length pocket-sized camera that produces extra fine images. I want something that I can carry around easily and yet get exceptional images. And I don't want to break the bank.
The Merrill DP1 and the GR are both very similar at first glance. They're similar looking, similar size and weight, and have similar lenses. They even have the same $800 MSRP. Yet they are also very different.
The differences mainly comes from the sensors contained within the cameras, and the built-in software. One camera is not necessarily better or worse than the other, they're just much different.
The Sigma camera has the Foveon sensor with 46 megapixels. Now, because of how this unique sensor works, it actually equates closer to 20 megapixels. The advantage of the Foveon sensor is that images at ISO 100 are stunningly amazing. They're super sharp with tons of fine detail and amazing color. These images also have a certain (but hard to describe) look that is unique to this sensor. The disadvantage of this sensor is that image quality quickly degrades as ISO increases, and it is almost unusable by ISO 800.
Other problems with the Merrill DP1 is that it is somewhat slow, battery life is very short and JPEGs look terrible.
The Ricoh GR has a 16 megapixel Sony sensor. This same sensor is found in many well-regarded cameras made by Sony, Nikon and Pentax. Yet Ricoh processes the data from the sensor just a little differently than those other cameras.
The GR interprets the data in such a way that the images have a film-like look. Just how film-like depends on what film one is comparing it to and what processes have been done to the file. From photographs that I have seen (from sources that I trust), the GR does an excellent job of making images that don't look, well, digital.
The GR has been said to have good-but-not-great high-ISO performance based on the amount of digital noise in the files. But the digital noise looks more like film grain than noise. Film grain has a look that is different than digital noise, and, frankly, grain can look quite good in an image while noise rarely does. So digital noise that looks like film grain is not a negative, but a positive.
The disadvantages of the GR is that it cannot quite match the Merrill DP1 at ISO 100. At ISO 200 it is pretty close, but at ISO 100 the Sigma camera is simply better. The GR is also susceptible to moire distortion (while the Merrill DP1 is not).
So the choice is between two cameras that are excellent, but in different ways. The Sigma Merrill DP1 has image quality at ISO 100 that is unmatched for price. In fact, one could spend triple what the Merrill DP1 costs and not match the image quality at ISO 100. Outside of ISO 100 image quality, the Ricoh GR is on par or better in almost every aspect.
Since the vast majority of my photographs are at low ISO, the Merrill DP1 is quite tempting. But the film-like quality and versatility of the GR is also tempting. If I could buy both I think I would. Right now, I'm still unsure which one I will buy.