In a recent discussion on the German Olympus forum I read that the
camera applies geometry conversions to images when converting them
to JPEG. I wasn't aware of that, so I tried
it out. Here images taken with my E-30 with the Zuiko Digital ED
12-60mm F2.8-4.0 SWD at focal lengths of 60 mm (first set) and 12 mm (second set). I
chose this lens because I know that it has significant barrel distortion at the short end
at close quarters. The test chart is of A4 size, and the short focal length images were
taken from about 32 cm distance.
In each group, the first image shows the raw image converted by DxO Optics “Pro” without
any correction. The second image is the JPEG from the camera, again with no corrections.
The third image is the raw image, again processed by DxO, but with geometry corrections.
Run the cursor over each image to see the difference from the following image. Click on an
image for progressively larger versions, up to original resolution (4032×3024).
As can be seen, the only difference between the raw and JPEG images from the camera is that,
for some reason, the JPEG is cropped differently. There is no evidence whatsoever of
geometry correction. DxO does better, but there's still some barrel distortion evident in
the second image.
