So, what to do. I have my Nikon gear for making the best quality images for my clients. Well, I'm not quite in the Hasselblad-65-Meg-digital-back-plus-camera-and-lenses league. But with my fairly new D800 and some good glass, I can get really high quality results.
Like many photographers, I need a camera which is with me all the time. A D800 with any lens is just too big and heavy. - Even my D7000 with a 40mm pancake lens doesn't fit the bill. - Too big.
I used to have a Panasonic Lumix LX5. Definitely small enough and with it's 24-90mm f2 lens, a great camera for high end snaps. But, for me just not up to it in low light, or for that matter, even in good light for landscapes. I want something which will be truly excellent even in quite low light situations, which is when so many opportunities occur.
My search would have 3 primary requirements.
1. A large(ish) and recent sensor for maximum low light capability.
2. Small enough to fit into a medium sized pocket.
3. Zoom or interchangeable lenses.
This ruled out all the compacts (sensor too small), and Sony's excellent NX range, as even with the small but rather poor 16mm pancake lens, it's APC sensor requires the lens to stick out just too far for pocketability.
I ended up staying with Panasonic, and buying the Lumix GX1 and the 20mm f1.7 lens. At 16 Megapixels and usable at ISO 3200, it has proved to a fantastic choice. I took it to a wedding and managed to put it in the breast pocket of my suit. Well it wasn't going to be a good look with a big bulge and straining button but it meant free hands for drinks and dancing!
Gx1 with 14mm f2.5 • Nikkor 50mm f1.8 AIS on Novaflex adapter • Panasonic 20mm f1.7
The next move was to find the right lenses - other than the 20mm - to give me the lightest, smallest travel kit possible, which could be used in low light and give properly high quality results.
The first choice, whilst small, might have to be replaced, or become an alternative to something bigger wider and better, Panasonic's truly tiny 14mm f2.5 pancake. Not fantastic image quality, and not quite wide enough to partner the 20mm, but usable for the moment.
I don't have an unlimited budget for this, so the next step was to make use of existing kit. I bought a Novoflex adapter. I read numerous reviews of cheaper options, but it seemed to me that for something long term and robust, I would have to spend the extra. Now I can use my old Nikkor 50mm f1.8 pancake - which with the adapter, makes a really quite small and very fast 100mm equivalent.
This image: 50mm Nikkor f1.8 AIS @ f1.8 on Panasonic GX1 with Novoflex lens adapter (100mm 35mm equivalent)
100% crop from above (at f1.8)
...and at f4
The next one up the range is perhaps better still. I have an 85mm f1.4D to give me an equivalent 170mm f1.4lens! Its still small enough to hang off my wrist while going for a walk on the wild side with the kids. Even at f1.4 the image quality using the centre of this lens is pretty darned good and by f2.8 it's fantastic. Using the adapter it's manual focus only and Aperture Priority or Manual exposure, but Panasonic's implementation of focus assist is so good, that whilst it's not going to work well for sport, it is still very usable for my type of work.
This kit is all about not missing an opportunity, and being able to get a really high quality image. As I shoot landscapes, the wide end is still taxing me. The Olympus 12mm f2 or 9-18mm zoom look like winners, but I can't spend that much money at the moment. Panasonic's 7-14mm would be fantastic, but way too expensive and still a bit big. In the short term, I either have to stick with the 14mm, or take my rather bulky 11-16mm f2.8 Tokina, which certainly delivers the quality and is wide enough.
It should be said that this is all a very personal requirement, but perhaps not that uncommon amongst professionals. Sony have just announced the very exciting RX1 with a full frame sensor and 35mm f2 lens. This is likely to be one of the best smallish cameras to carry around in low light. Still too big for a pocket though!