Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: What is the difference between this lens and the 14-42mm that is NOT "version ii?"
Document: That was something not possible with the larger Version I lens on the GF5. The zooming motion of the new 14-42mm lens is smooth which is great for those who shoot videos. If you are familiar with Panasonic's 45-150mm lens the zooming smoothness and build is similar to that.
That makes 2 versions of the 14-42mm Version II lens; a plastic mount for kits and metal mount for boxed, retail. Because some people may end up buying the lens used or some sellers may sell the lens from a broken up kit, please be aware of which you are buying if the mount is something important to you.
I decided to buy this lens because of the strong endorsement and score it receives from DXO mark. I've not been disappointed. I've uploaded an image taken with this lens of a balloon seller in Pondicherry, India. The image shows the surprising amount of sharpness that the lens delivers. I had the first version of the 14-42mm kit lens, which came with my G5, but I sold that because it was very stiff when zooming.
The new Panasonic 14-42mm II lens is a welcome update from the previous 14-42mm lens. The Version II lens has a better build quality, has a much smoother zoom, and is substantially smaller. At 1.9" long it is 0.6" shorter than the Version I lens and at 2.2" wide it is 0.2" narrower, making it downright tiny for a zoom lens.
At the wider angle focal lengths the image quality looks the same between the 2 lenses, sharp center and soft edges and corners. At 35mm, the Version II lens does looks a touch sharper overall. At 42mm, the Version I lens looks a touch sharper overall.
This model is also more compact than the first edition of the 14-42mm kit lens.
The zoom action is also much smoother than the 14-45. If you shoot video, this is a better lens.
This is a very small and light lens, compared to the Lumix 14-45mm kit lens. Although it's largely made of plastic, including the mount, the overall finish is good. My old 14-45mm lens had the rubber ring becoming loose after a while. It won't happen to this lens because the zoom and focus ring are both one-piece plastic.This is not the sharpest lens. If you want a very sharp lens without spending a lot of money, get the 14-45.
I wish it was faster in the telephoto range but for the price it beats my Canon DSLR EF lenses hands down at less than a third of the price. The build quality is very good and attached to the Lumix camera the performance, especially in the virtual absence of chromatic aberration is exceptional. It comes with a lens hood, a nice plus. The filter size is the same as my 14 mm f/2.5 pancake lens.I ordered this through Amazon from Japan.
Excellent quality lens for the money. Very happy with this lens.
Answer: I've had both. They both have the same light gathering abilities, but the version II is smaller and is a bit better optically the the original 14-42, although I think you'd be hard pressed to see the difference in most situations. The version II is a smoother lens, mechanically.