The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Olympus M 25mm F1.8 and the Sony FE 50mm F1.4 GM 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. Sony FE 50mm F1.4 GM is the longer of the two lenses at 96mm. The Olympus M 25mm F1.8 with a length of 41mm, is 55mm shorter. Besides being longer, the Sony FE 50mm F1.4 GM also has a larger diameter of 81mm compared to the Olympus M 25mm F1.8's 56mm 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 25mm F1.8 weighs 136g, which means it is 380g (73%) lighter than the Sony FE 50mm F1.4 GM which has a weight of 516g.
Filter Threads
The Olympus M 25mm F1.8 has a filter size of 46mm whereas the Sony FE 50mm F1.4 GM has a 67mm 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 Olympus M 25mm F1.8:
And these are the 67mm filters that we recommend for the Sony FE 50mm F1.4 GM:
Lens Mounts
The Olympus M 25mm F1.8 has the Micro Four Thirds lens mount whereas the Sony FE 50mm F1.4 GM has the Sony E 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 Sony FX5, Sony A7R VI and Sony A7 V for the Sony E Mount.
Focal Range
Olympus M 25mm F1.8 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.
On the other hand, the Sony FE 50mm F1.4 GM is a prime lens with fixed focal lenght of 50mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 75mm.