The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Panasonic X 35-100mm F2.8 II Power OIS and the Olympus ED 40-150mm F2.8 Pro 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 ED 40-150mm F2.8 Pro is the longer of the two lenses at 160mm. The Panasonic X 35-100mm F2.8 II Power OIS with a length of 100mm, is 60mm shorter. Besides being longer, the Olympus ED 40-150mm F2.8 Pro also has a larger diameter of 79mm compared to the Panasonic X 35-100mm F2.8 II Power OIS's 67mm 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. Panasonic X 35-100mm F2.8 II Power OIS weighs 357g, which means it is 403g (53%) lighter than the Olympus ED 40-150mm F2.8 Pro which has a weight of 760g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Micro Four Thirds Mount for size comparison purposes.
Telephoto Lenses in Micro Four Thirds Mount for Size Comparison
Filter Threads
The Panasonic X 35-100mm F2.8 II Power OIS has a filter size of 58mm whereas the Olympus ED 40-150mm F2.8 Pro has a 72mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 58mm filters that we recommend you to consider for the Panasonic X 35-100mm F2.8 II Power OIS:
And these are the 72mm filters that we recommend for the Olympus ED 40-150mm F2.8 Pro:
Lens Mounts
Both the Panasonic X 35-100mm F2.8 II Power OIS and the Olympus ED 40-150mm F2.8 Pro 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
Panasonic X 35-100mm F2.8 II Power OIS has a focal range of 35-100mm and
2.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
70-200mm when used on a FourThirds format camera.
On the other hand, the Olympus ED 40-150mm F2.8 Pro has a focal range of 40-150mm and 3.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 80-300mm when used on a FourThirds format camera.