The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Panasonic 20mm F1.7 II ASPH and the Olympus 25mm f2.8 Pancake 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 II ASPH is the longer of the two lenses at 26mm. The Olympus 25mm f2.8 Pancake with a length of 24mm, is 2mm shorter. On the other hand, the Olympus 25mm f2.8 Pancake has a larger diameter of 64mm compared to the Panasonic 20mm F1.7 II ASPH's 63mm 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. Panasonic 20mm F1.7 II ASPH weighs 87g, which means it is 8g (8%) lighter than the Olympus 25mm f2.8 Pancake which has a weight of 95g.
Filter Threads
The Panasonic 20mm F1.7 II ASPH has a filter size of 46mm whereas the Olympus 25mm f2.8 Pancake has a 43mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 46mm filters that we recommend you to consider for the Panasonic 20mm F1.7 II ASPH:
And these are the 43mm filters that we recommend for the Olympus 25mm f2.8 Pancake:
Lens Mounts
The Panasonic 20mm F1.7 II ASPH has the Micro Four Thirds lens mount whereas the Olympus 25mm f2.8 Pancake has the Four Thirds lens mount. Some of the latest released cameras that are compatible with these mounts are OM System OM-3 Astro, OM System OM-5 II and OM System OM-3 for the Micro Four Thirds Mount and Olympus E-5, Olympus E-600 and Olympus E-620 for the Four Thirds Mount.
Focal Range
Panasonic 20mm F1.7 II 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.
On the other hand, the Olympus 25mm f2.8 Pancake 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.
