The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Venus 100mm F2.8 2X Ultra Macro and the Hartblei 80mm F2.8 IF TS for their suitability to various photography scenarios:
Size and Weight Comparison
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Venus 100mm F2.8 2X Ultra Macro weighs 638g, which means it is 212g (24%) lighter than the Hartblei 80mm F2.8 IF TS which has a weight of 850g.
Lens Mounts
The Venus 100mm F2.8 2X Ultra Macro has the Pentax KAF2 lens mount whereas the Hartblei 80mm F2.8 IF TS has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax KF, Pentax K-3 III and Pentax K-1 II for the Pentax KAF2 Mount and Pentax KF, Pentax K-3 III and Pentax K-1 II for the Pentax KAF Mount.
Venus 100mm F2.8 2X Ultra Macro is also available in Canon EF , Nikon F (FX) and Sony E mounts.
Hartblei 80mm F2.8 IF TS is also available in Canon EF , Sony Alpha and Nikon F (FX) mounts.
Focal Range
Venus 100mm F2.8 2X Ultra Macro is a prime lens with fixed focal lenght of 100mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 150mm.
Hartblei 80mm F2.8 IF TS is a prime lens with fixed focal lenght of 80mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 120mm.