[Darktable] Lens distorted

Hi,

I discover the world of Raw. How will correct this. I have a Nikon Coolpix B700. His profile is not available in tool '“lens correction”. There are solution or a turn arround ?

Is that the camera alone or did you add a wide angle lens?

http://lensfun.sourceforge.net/lenslist/
http://lensfun.sourceforge.net/calibration/

@ Ofnuts : yes is that the camera alone ! It’s not normal ?
@ LebedevRI : thanks, i look that !

No. You shouldn’t have the circular cuts in the corners. Sample shots I find from the same camera don’t have them.

Using a lens hood which is too narrow? Or a filter which is too thick? Your other pictures don’t seem to suffer from this…

The problem with your picture isn’t that much lens distortion. The converging verticals happened because your camera was shooting above the horizontal. This is corrected by the perspective correction.

PS: did you notice that the underside of the bridge is used as storage by the homeless?

Actually yes, this is normal for those types of cameras. From RawPedia,

Raw images from bridge-type cameras often show very strong vignetting in the corners, and strong distortion, while the JPEG images do not show this. The way these cameras deal with the vignetting problem is by fixing the distortion which pushes the corners further out beyond the image borders. They are then simply cropped off. Do not expect to fix this strong corner vignetting problem seen in bridge-type cameras by using LCP profiles - often the corners do not contain any actual image data, just the blurred, dark corners of your lens hood. Do as the camera does, and eliminate vignetting by fixing the distortion which will push the vignetting out of view.

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exiv2 -pt IMG_XX.JPG | grep -i lens

The other pictures may suffer as well. If an image has not been touched, the embedded preview is shown as thumbnail. And if I got it correct only wide angle shots would be affected.

… unless don't use embedded preview JPEG but half-size raw preference is enabled.

Ugh. Thanks for the heads up.

In case someone have the same question it again, I solved, in Darktable 3.0, it using perspective correction over:

post perspective correction:

image

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Well how did that happen?. You you are using a lens then the corners were not supposed to come like this. Anyways you can always crop it out.