The K-x works really bad under low light.
At night, its almost useless.
But I do admit in the day, I love it paired with the 28-75 f2.8.
But bcos of the weight & bulkiness I decided to switch to a mirrorless.
I dun wished to get anymore accessories.
I just want to kit to work well for me under low light and in e day.
I know nuts about mirrorless camera.
And only managed to hands on Sony C3, 5N & Nikon J1, V1.
So was asking if any own a mirrorless which works very well for them as kit.
In low light, every camera AF will struggle in low contrast.
Its not brand or camera type dependent and perhaps a bit better with really high end professional line cameras (eg. 7D; D3 ) which have a more sensitive AF module.
You have to focus on an area that has better contrast.
Even with the so claimed 'world's fastest AF' on the current EP3 and G3, GX1 m4/3 cameras using contrast detect AF, if you point the AF area on an area without contrast, the cameras can't focus (in low light or bright sunshine).
Eg.
So if you focused on the persons cheeks (all flesh color), the camera will not focus. If you focused on an area with the eye and flesh color (ie. black eye, brows, etc against a flesh color), it will.
Its a 'known' issue on any camera.
http://www.clubsnap.com/forums/general-tech-talk/1025282-low-light-af-performance-culprit.html
Anyway, I guess you want a layman answer and a bottom line to the question.
So my few cents :
1. Learn about how to AF in low light (ie. focus on areas of contrast)
2. Yes, a m4/3 camera is lighter and smaller
3. You will need good fast prime lenses for m4/3 to use these camera at its best (esp. in low light) and work round its poorer ISO performance in those conditions
4. Luckily, the primes mentioned in #3 are pretty cheap and should cost you about $1300 for a set of 3 nice lenses (14/2.5; 20/1.7; 45/1.8)
pinholecam :
How's the GX1.?
You got to know what you are getting into with a GX1.
GX1 = no EVF (can attach a separate one, but you need to buy one at additional cost)
You can also look at Olympus with its EP3 and EPL3
It also means holding and shooting it like a pns camera so be prepared for a usage change.
I can't say for certain how the GX1 performs since I don't have it, but it should be rather similar to the G3 since they have a rather similar sensor.
Reviews are pretty preliminary at the moment for the GX1.
You can do a google for review if they are avaliable.