The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax D FA 150-450mm F4.5-5.6 ED DC AW and the Pentax DA 300mm F4.0 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 D FA 150-450mm F4.5-5.6 ED DC AW is the longer of the two lenses at 242mm. The Pentax DA 300mm F4.0 ED with a length of 184mm, is 58mm shorter. Besides being longer, the Pentax D FA 150-450mm F4.5-5.6 ED DC AW also has a larger diameter of 95mm compared to the Pentax DA 300mm F4.0 ED's 83mm 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 300mm F4.0 ED weighs 1070g, 46% (930g) lighter than the Pentax D FA 150-450mm F4.5-5.6 ED DC AW's weight of 2000g.
Filter Threads
The Pentax D FA 150-450mm F4.5-5.6 ED DC AW has a filter size of 86mm whereas the Pentax DA 300mm F4.0 ED has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 86mm filters that we recommend you to consider for the Pentax D FA 150-450mm F4.5-5.6 ED DC AW:
And these are the 77mm filters that we recommend for the Pentax DA 300mm F4.0 ED:
Lens Mounts
The Pentax D FA 150-450mm F4.5-5.6 ED DC AW has the Pentax KAF3 lens mount whereas the Pentax DA 300mm F4.0 ED has the Pentax KAF2 lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III for the Pentax KAF3 Mount and , and for the Pentax KAF2 Mount.
Focal Range
Pentax D FA 150-450mm F4.5-5.6 ED DC AW has a focal range of 150-450mm and
3.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
225 - 675mm.
On the other hand, the Pentax DA 300mm F4.0 ED is a prime lens with fixed focal lenght of 300mm which has an effective (full-frame 35mm equivalent) focal range of 450mm when used on a APS-C / DX format camera.