The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Olympus M 17mm f2.8 Pancake and the Panasonic 20mm F1.7 ASPH for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Panasonic 20mm F1.7 ASPH is the longer of the two lenses at 26mm. The Olympus M 17mm f2.8 Pancake with a length of 22mm, is 4mm shorter. Besides being longer, the Panasonic 20mm F1.7 ASPH also has a larger diameter of 63mm compared to the Olympus M 17mm f2.8 Pancake's 57mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. Olympus M 17mm f2.8 Pancake weighs 71g, which means it is 29g (29%) lighter than the Panasonic 20mm F1.7 ASPH which has a weight of 100g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Micro Four Thirds Mount for size comparison purposes.
Wideangle Lenses in Micro Four Thirds Mount for Size Comparison
Filter Threads
The Olympus M 17mm f2.8 Pancake has a filter size of 37mm whereas the Panasonic 20mm F1.7 ASPH has a 46mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 37mm filters that we recommend you to consider for the Olympus M 17mm f2.8 Pancake:
And these are the 46mm filters that we recommend for the Panasonic 20mm F1.7 ASPH:
Lens Mounts
Both the Olympus M 17mm f2.8 Pancake and the Panasonic 20mm F1.7 ASPH 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-1 II, Panasonic G9 II and OM System OM-5.
Focal Range
Olympus M 17mm f2.8 Pancake is a prime lens with fixed focal lenght of 17mm which has an effective (full-frame 35mm equivalent) focal range of
34mm when used on a FourThirds format camera.
On the other hand, the Panasonic 20mm F1.7 ASPH is a prime lens with fixed focal lenght of 20mm which has an effective (full-frame 35mm equivalent) focal range of 40mm when used on a FourThirds format camera.