The Fantastic Lumix G7

I am 100% sure the best lens for your G7 under $500 is the $330 Sigma 30mm f1.4. I only do street photography and landscape videos. You would think 30mm is too tight, but it really is not. I am forced to be a little more selective which make me choose the best area of a landscape and gets me more personal street shots.

• The bokeh is good, and ultra easy to get with the focal length and f1.4
• It works awesomely at night (lets the same amount of light on the sensor as the $1200 Olympus 25 f1.2).
• It isn't as big and heavy as some people make out. But it is far from the pancakes.
• It is far superior to all but one lens I have owned under $500. The one lens which compares is the Sigma 60mm f2.8, but that is not a "1 prime lens" as it is long. It beats the PL15, P20, P14, O25 f1.8, P25 f1.7, O17 2.8 and 2 of those lenses are more expensive.
• It is a bona fide bargain. Stunning sharpness and pop with images that seem to shine. I dropped my bag the other day thought I broke it, but wasn't bothered as I would have happily instantly bought another one because it is worth 2-3 times the price.

You have a great kit lens and the other primes I mentioned arent much sharper (you need to pixel peep to spot a slight difference), whereas there is a massive difference with the Sigma. Having the zoom for when you need stabilization or want to go wide in the day is the ideal companion. I use the lesser quality 12-32 kit lens as it is so pocketable and wider.

I recommend you try it in a store and compare it with the PL15mm and the Oly 25 1.8. Those 2 smaller lenses are convenient but over rated. I only have the 25 for when I need to go lighter and image quality isnt too important. The PL15 is charming with the way it is made and it does render nicely, but it really isn't different enough from a kit zoom to justify the purchase imho.

Coming from Canon I expect you will be happy with the Sigma's weight. Soon after you will no doubt want to get the 60 too, which is more like $200. I spent 3+ hours street shooting with the 60 yesterday and some today, it is too good to save for just things like portraits. I got lots of wow moments when reviewing the photos later, which only seems to happen with the Sigmas and rarely with the PL15. Then they will release the 16mm f1.4 to complete an amazingly sharp "holy trinity".