The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Panasonic 42.5mm F1.7 OIS and the Panasonic Leica 25mm F1.4 for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Panasonic Leica 25mm F1.4 is the longer of the two lenses at 55mm. The Panasonic 42.5mm F1.7 OIS with a length of 50mm, is 5mm shorter. Besides being longer, the Panasonic Leica 25mm F1.4 also has a larger diameter of 63mm compared to the Panasonic 42.5mm F1.7 OIS's 55mm diameter.
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Panasonic 42.5mm F1.7 OIS weighs 130g, which means it is 70g (35%) lighter than the Panasonic Leica 25mm F1.4 which has a weight of 200g.
Below you can find the dimension and weight table of the Standard Prime Lenses in Micro Four Thirds Mount for size comparison purposes.
Standard Prime Lenses in Micro Four Thirds Mount for Size Comparison
Lens Mounts
Both the Panasonic 42.5mm F1.7 OIS and the Panasonic Leica 25mm F1.4 has the same Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with the Micro Four Thirds lenses are OM System OM-5, Panasonic GH6 and OM System OM-1.
Panasonic Leica 25mm F1.4 is also available in Four Thirds mount.
Focal Range
Panasonic 42.5mm F1.7 OIS is a prime lens with fixed focal lenght of 43mm which has an effective (full-frame 35mm equivalent) focal range of 86mm when used on a FourThirds format camera. Panasonic Leica 25mm F1.4 is a prime lens with fixed focal lenght of 25mm which has an effective (full-frame 35mm equivalent) focal range of 50mm when used on a FourThirds format camera.