The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Olympus ED 100-400mm F5.0-6.3 IS and the Olympus 150-400mm F4.5 TC 1.25x IS 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. Olympus 150-400mm F4.5 TC 1.25x IS is the longer of the two lenses at 314mm. The Olympus ED 100-400mm F5.0-6.3 IS with a length of 206mm, is 108mm shorter. Besides being longer, the Olympus 150-400mm F4.5 TC 1.25x IS also has a larger diameter of 116mm compared to the Olympus ED 100-400mm F5.0-6.3 IS's 86mm 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. Olympus ED 100-400mm F5.0-6.3 IS weighs 1120g, which means it is 730g (39%) lighter than the Olympus 150-400mm F4.5 TC 1.25x IS which has a weight of 1850g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Micro Four Thirds Mount for size comparison purposes.
Super Telephoto Lenses in Micro Four Thirds Mount for Size Comparison
Filter Threads
The Olympus ED 100-400mm F5.0-6.3 IS has a filter size of 72mm whereas the Olympus 150-400mm F4.5 TC 1.25x IS has a 95mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 72mm filters that we recommend you to consider for the Olympus ED 100-400mm F5.0-6.3 IS:
And these are the 95mm filters that we recommend for the Olympus 150-400mm F4.5 TC 1.25x IS:
Lens Mounts
Both the Olympus ED 100-400mm F5.0-6.3 IS and the Olympus 150-400mm F4.5 TC 1.25x IS has the same Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with the Micro Four Thirds lenses are OM System OM-1 II, Panasonic G9 II and OM System OM-5.
Focal Range
Olympus ED 100-400mm F5.0-6.3 IS has a focal range of 100-400mm and
4.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
200-800mm when used on a FourThirds format camera.
On the other hand, the Olympus 150-400mm F4.5 TC 1.25x IS has a focal range of 150-400mm and 2.7X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 300-800mm when used on a FourThirds format camera.