The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 135mm F2.0 ED UMC and the Pentax DA 200mm F2.8 ED 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. Pentax DA 200mm F2.8 ED is the longer of the two lenses at 134mm. The Samyang 135mm F2.0 ED UMC with a length of 122mm, is 12mm shorter. Besides being longer, the Pentax DA 200mm F2.8 ED also has a larger diameter of 83mm compared to the Samyang 135mm F2.0 ED UMC's 82mm 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 DA 200mm F2.8 ED weighs 825g, 0% (5g) lighter than the Samyang 135mm F2.0 ED UMC's weight of 830g.
Below you can find the dimension and weight table of the Telephoto Prime Lenses in Pentax KAF Mount for size comparison purposes.
Telephoto Lenses in Pentax KAF Mount for Size Comparison
Filter Threads
Both the Samyang 135mm F2.0 ED UMC and the Pentax DA 200mm F2.8 ED have the same Filter thread size of 77mm.
Below are links to the 77mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Samyang 135mm F2.0 ED UMC and the Pentax DA 200mm F2.8 ED has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III.
Samyang 135mm F2.0 ED UMC is also available in the Canon EF , Canon EF-M, Four Thirds, Fujifilm X, Micro Four Thirds, Nikon F (FX), Samsung NX, Sony Alpha and Sony E mounts.
Focal Range
Samyang 135mm F2.0 ED UMC is a prime lens with fixed focal lenght of 135mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
202.5mm.
On the other hand, the Pentax DA 200mm F2.8 ED is a prime lens with fixed focal lenght of 200mm which has an effective (full-frame 35mm equivalent) focal range of 300mm when used on a APS-C / DX format camera.
