The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax 70mm F2.4 AL L 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. Pentax 70mm F2.4 AL L weighs 130g, which means it is 720g (84%) lighter than the Hartblei 80mm F2.8 IF TS which has a weight of 850g.
Lens Mounts
Both the Pentax 70mm F2.4 AL L and the Hartblei 80mm F2.8 IF TS has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax KF, Pentax K-3 III and Pentax KP.
Pentax 70mm F2.4 AL L is also available in Pentax KAF mount.
Hartblei 80mm F2.8 IF TS is also available in Canon EF , Sony Alpha and Nikon F (FX) mounts.
Focal Range
Pentax 70mm F2.4 AL L is a prime lens with fixed focal lenght of 70mm which has an effective (full-frame 35mm equivalent) focal range of 105mm when used on a APS-C / DX format camera. 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 an 35mm (FF) equivalent of 120mm.