Moving subjects in low light, perhaps from a fixed shooting position without concern over the size and weight of equipment - this is the realm of full frame. The announcement of the Sony A7 III last week has caused concern on some forums, this being a mature, sub £2000 full frame mirrorless which seriously challenges the dominance of DSLRs at this price point and of course the higher end micro four thirds cameras. Whilst the new Olympus f/1.2 lenses will give you some improvements in shutter speed or ISO, zooms are often preferable in more dynamic situations, despite loosing a stop or so in speed and therefore higher ISO is needed. Micro Four Thirds doesn’t beat everything in every situation for sure.

I don’t doubt the 17mm f1.2 will give the best image quality the Olympus OM-D E-M1 Mark II is capable of - I also don’t expect this to be as good as the Zeiss Milvus 35mm was on my Nikon D750, which in turn would not be as good as a Shneider Kreuznach 55mm on a Phase One medium format body.
The ability to get a better result in a different format wouldn’t stop me buying the best available for my chosen format. It is always diminishing marginal returns at the “top end” - I’ll need to look at some more real world pictures and probably hire / borrow the lens myself and make some prints to decide if the improvement is worthwhile.

Am I saying that full frame has become a specialist tool - for extreme situations?

My needs are for a fast performing, compact and versatile system so I can continue my core interest of street photography and also try new things. The Olympus OM-D E-M1 II will never match my Nikon D750 for outright image quality at high ISO - but for general use, I can walk around with a discreet and very light 24 / 90 lens combination of comparable quality and a fraction of the weight and size.

I fully accept that in a few years I may change system once again, but in the meantime I am shooting more as I have great versatility. I have of course also enjoyed taking pictures with older systems far less capable than those of today (including Nikon pro bodies) but the E-M1 II is the best “compromise” for me right now.

Many would see my move from full frame Nikon to micro four thirds as a downgrade, but aside from the versatility, there are other clear advantages for me. There is the obvious size and weight difference, for my choice of lenses a 35mm and 90mm equivalent, the Olympus system is 810g rather than the Nikon D750 1.8/35mm and 1.8/85mm at 1495g. And the weather sealing with the Olympus is as good as it gets.

Olympus vs a downpour!

And a lot remains comparable.

Quality - It’s easily good enough, particularly as the vast majority of my images are at base to 800 ISO.

Speed of the system - I don’t feel I am slower than with my D750 in most conditions. 

Ergonomics - No longer are smaller sensor cameras handicapped by un-holdable bodies, manufacturers now realise there is an advantage to a chunkier camera.

Without doubt if I did a lot of low light in dynamic / moving situations I would go Sony / Nikon FF. If I needed best image quality, for large landscape or fine art prints, I would likely go Fuji GFX.

As I said in a previous article, in film days, nobody would have seriously considered a Hasselblad medium format camera as an alternative to a Leica M6 or Nikon FM but many photographers used both.