Panasonic Leica DG Vario-Elmarit 8-18 mm f/2.8-4 ASPH.
6. Distortion
Olympus E-M5 II, JPEG, 8 mm | |||
Olympus E-M5 II, JPEG, 10 mm | |||
Olympus E-M5 II, JPEG, 13 mm | |||
Olympus E-M5 II, JPEG, 18 mm | |||
At the shortest focal length you deal with a ‘barrel’ variety of that aberration, amounting to −1.59%. At 10 mm it decreases to an imperceptible level of −0.37%. At 13 mm you still deal with barrel distortion but, within the margin of error, the results are equal with zero (official result being −0.14%). Pincushion distortion is negligible as well, amounting to +0.32; you can observe that effect only at the maximum focal length.
Please Support UsIf you enjoy our reviews and articles, and you want us to continue our work please, support our website by donating through PayPal. The funds are going to be used for paying our editorial team, renting servers, and equipping our testing studio; only that way we will be able to continue providing you interesting content for free. |
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
After passing to RAW files the situation changes dramatically and photos below show it very well.
Olympus E-M5 II, RAW, 8 mm | |||
Olympus E-M5 II, RAW, 10 mm | |||
Olympus E-M5 II, RAW, 13 mm | |||
Olympus E-M5 II, JPEG, 18 mm | |||
At 8 mm distortion is huge. You deal with its barrel variety and its level amounts to as much as −6.59%. Of course it can be corrected but only at a cost. Firstly, the field of view has to be cropped but it is a smaller problem than you might think because, fortunately, the Micro 4/3 optics producers state fields of view already after distortion correction. Another effect might be a more serious problem, though.
Unfortunately the Panaleica’s 8-18 mm distortion level decreases quite slowly with the increase of the focal length. At 10 mm you deal with a still high level of −4.51%. Barrel distortion is also noticeable at 13 mm where it reaches −1.68%. Only at 18 mm you see just slight ‘pincushion’ of +0.32%.