The type of photography that you are planning to use is an important decision factor. Here we have evaluated the HD Pentax-FA 77mm F1.8 Ltd and the Voigtlander 90mm F3.5 SL II 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. Voigtlander 90mm F3.5 SL II is the longer of the two lenses at 52mm. The HD Pentax-FA 77mm F1.8 Ltd with a length of 48mm, is 4mm shorter. On the other hand, the HD Pentax-FA 77mm F1.8 Ltd has a larger diameter of 64mm compared to the Voigtlander 90mm F3.5 SL II'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. HD Pentax-FA 77mm F1.8 Ltd weighs 270g, which means it is 50g (15%) lighter than the Voigtlander 90mm F3.5 SL II which has a weight of 320g.
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
The HD Pentax-FA 77mm F1.8 Ltd has a filter size of 49mm whereas the Voigtlander 90mm F3.5 SL II has a 52mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 49mm filters that we recommend you to consider for the HD Pentax-FA 77mm F1.8 Ltd:
And these are the 52mm filters that we recommend for the Voigtlander 90mm F3.5 SL II:
Lens Mounts
Both the HD Pentax-FA 77mm F1.8 Ltd and the Voigtlander 90mm F3.5 SL II 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 Monochrome, Pentax KF and Pentax K-3 III.
Voigtlander 90mm F3.5 SL II is also available in Canon EF and Nikon F (FX) mounts.
Focal Range
HD Pentax-FA 77mm F1.8 Ltd is a prime lens with fixed focal lenght of 77mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
115.5mm.
On the other hand, the Voigtlander 90mm F3.5 SL II is a prime lens with fixed focal lenght of 90mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 135mm.