The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Panasonic S 40mm F2 and the Panasonic 20mm F1.7 II 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 S 40mm F2 is the longer of the two lenses at 41mm. The Panasonic 20mm F1.7 II ASPH with a length of 26mm, is 15mm shorter. Besides being longer, the Panasonic S 40mm F2 also has a larger diameter of 69mm 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, 39% (57g) lighter than the Panasonic S 40mm F2's weight of 144g.
Filter Threads
The Panasonic S 40mm F2 has a filter size of 62mm whereas the Panasonic 20mm F1.7 II 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 62mm filters that we recommend you to consider for the Panasonic S 40mm F2:
And these are the 46mm filters that we recommend for the Panasonic 20mm F1.7 II ASPH:
Lens Mounts
The Panasonic S 40mm F2 has the Leica L lens mount whereas the Panasonic 20mm F1.7 II ASPH has the Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with these mounts are Leica SL3-P, Panasonic S1 II and Panasonic S1 IIE for the Leica L Mount and OM System OM-3 Astro, OM System OM-5 II and OM System OM-3 for the Micro Four Thirds Mount.
Focal Range
Panasonic S 40mm F2 is a prime lens with fixed focal lenght of 40mm.
On the other hand, the 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.
