A word (or three) about sensor formats…
While I am a Fujifilm X-Series devotee, and long-time Nikon user, I actually keep APS-C, full frame and m4/3 cameras in my arsenal, as each serves a specific need, depending upon the situation. More and more, Fujifilm X-Series APS-C cameras now shoulder 60-70% of my personal and professional workload, however, as they tend to sit in the “goldilocks zone” of overall usability vs image quality … and it’s now my overall preferred system because of this and the system I reach for first.
The pro-DSLR (Nikon D3s) comes out when the envelope is stretched: extremely fast action, extremely low light where the D3s’ famous full frame low light capabilities are legendary, or any situation where the physical conditions are so ridiculously extreme that they might make a lesser camera stammer, shudder, and then curl up in a ball, and whenever I need to make use of Nikon’s unmatched CLS (Creative Lighting System).
Meanwhile, what’s all this about m4/3?
Well, the Olympus OM-D cameras offer twice the depth of field of full frame at the same apertures, which can be hugely advantageous under certain (daylight) shooting conditions where focus might be harder to achieve. Combined with IBIS that works on both their PRO series zoom lenses and their excellent premium prime lenses, the corner-to-corner sharpness, compact size, and extremely fast operational speed make this system ideal for tight spaces and discreet operation … particularly since Olympus recently added a fully silent electronic shutter option to the E-M1 in the camera’s last firmware update. The touch screen capabilities with “touch to focus” and/or “touch to shoot” can also be invaluable at times if one is trying to steal candid shots without being noticed.
I find Olympus works best, however, between ISO 200-800, and I don’t like to push it past ISO 1600. It’s simply a limitation of the smaller sensor; no replacement for displacement, as it were. At these higher ISOs, the Fujifilm cameras pull away, with less visible noise, and about a 1 to 1.5 stop advantage, IMO — possibly even slightly more with the new X-Pro2 (which, of course, also offers more resolution).
At base ISOs, however, it’s harder to spot the differences between the two formats. Tonal transitions remain more gradual with larger sensors, certainly, with m4/3 images often appearing a bit more contrasty and linear than their Fujifilm equivalents. This can either be a disadvantage, or an advantage, depending upon the look one is after and the subject matter one is photographing.
So what does that mean for the current state of m4/3 IQ, you ask? Dynamic range is slightly above 12 stops at base ISO (it’s important to remember that this starts to drop as you climb the ISO scale). In concert with careful post-processing, you should be able to produce very good quality prints up to A3+ (13″x 19″) at ISO 1600 with cameras like the E-M1, and easily up to a 16″x20″ print, and sometimes even larger, if your shot discipline is good and you’ve kept at or below ISO 800.
In practical terms? Easily good enough for a double-truck in a magazine. And truthfully, the vast majority of people never even make 16×20″ prints.
Olympus, of course, have long made a fine lineup of cameras, going all the way back to the original OM-1 and OM-2 35mm models that debuted in the 1970s, which I associate with some of my earliest and fondest memories of photography. They’re renowned for being small, powerful instruments with excellent optics, and like both Fujifilm and Nikon have a storied history in the annals of photography.