The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Olympus 25mm f2.8 Pancake and the Rokinon 24mm f1.4 for their suitability to various photography scenarios:
Size and Weight Comparison
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 25mm f2.8 Pancake weighs 95g, which means it is 485g (83%) lighter than the Rokinon 24mm f1.4 which has a weight of 580g.
Filter Threads
The Olympus 25mm f2.8 Pancake has a filter size of 43mm whereas the Rokinon 24mm f1.4 has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 43mm filters that we recommend you to consider for the Olympus 25mm f2.8 Pancake:
And these are the 77mm filters that we recommend for the Rokinon 24mm f1.4:
Lens Mounts
Both the Olympus 25mm f2.8 Pancake and the Rokinon 24mm f1.4 has the same Four Thirds lens mount. Some of the latest released cameras that are compatible with the Four Thirds lenses are Olympus E-5, Olympus E-600 and Olympus E-620.
Rokinon 24mm f1.4 is also available in Canon EF , Nikon F (FX), Pentax KAF, Sony Alpha and Samsung NX mounts.
Focal Range
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.
On the other hand, the Rokinon 24mm f1.4 is a prime lens with fixed focal lenght of 24mm.