The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Panasonic S 50mm F1.8 and the Pentax 15mm F4 ED AL L 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 50mm F1.8 is the longer of the two lenses at 82mm. The Pentax 15mm F4 ED AL L with a length of 40mm, is 42mm shorter. Besides being longer, the Panasonic S 50mm F1.8 also has a larger diameter of 74mm compared to the Pentax 15mm F4 ED AL L'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. Pentax 15mm F4 ED AL L weighs 189g, 37% (111g) lighter than the Panasonic S 50mm F1.8's weight of 300g.
Filter Threads
The Panasonic S 50mm F1.8 has a filter size of 67mm whereas the Pentax 15mm F4 ED AL L has a 49mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Panasonic S 50mm F1.8:
And these are the 49mm filters that we recommend for the Pentax 15mm F4 ED AL L:
Lens Mounts
The Panasonic S 50mm F1.8 has the Leica L lens mount whereas the Pentax 15mm F4 ED AL L has the Pentax KAF 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 Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Focal Range
Panasonic S 50mm F1.8 is a prime lens with fixed focal lenght of 50mm.
On the other hand, the Pentax 15mm F4 ED AL L is a prime lens with fixed focal lenght of 15mm which has an effective (full-frame 35mm equivalent) focal range of 22.5mm when used on a APS-C / DX format camera.
