The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Irix 45mm F1.4 and the Samsung D-Xenon 16-45mm F4 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. Samsung D-Xenon 16-45mm F4 weighs 365g, 60% (560g) lighter than the Irix 45mm F1.4's weight of 925g.
Filter Threads
The Irix 45mm F1.4 has a filter size of 77mm whereas the Samsung D-Xenon 16-45mm F4 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 77mm filters that we recommend you to consider for the Irix 45mm F1.4:
And these are the 67mm filters that we recommend for the Samsung D-Xenon 16-45mm F4:
Lens Mounts
Both the Irix 45mm F1.4 and the Samsung D-Xenon 16-45mm F4 has the same Pentax KAF2 lens mount. Some of the latest released cameras that are compatible with the Pentax KAF2 lenses are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III.
Irix 45mm F1.4 is also available in the Canon EF and Nikon F (FX) mounts.
Focal Range
Irix 45mm F1.4 is a prime lens with fixed focal lenght of 45mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
67.5mm.
On the other hand, the Samsung D-Xenon 16-45mm F4 has a focal range of 16-45mm and 2.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 24-67.5mm when used on a APS-C / DX format camera.
