How does DxO assign an optical module to an image, and what are the limitations of this process?

This information applies to all versions

To identify the equipment used to shoot an image and assign it to an optics module, we use various Exif/MakerNote metadata in the following order:

1. LensName
2. LensID
3. LensInfo (for example 18-35mm F3.5-5.6)
4. Current focus and aperture settings

Information 1 and 2 are not always available, especially for cameras of older generations. Any of the other information could apply to multiple lenses. 1 and 2 are supposed to be unique but manufacturers do not always respect that.

So when a module for a camera-lens pair doesn't exist yet, DxO PhotoLab might suggest a module for one or more other lenses.

If a manual lens is used then some Exif information will be missing:

• lens identification (LensName, LensID, LensInformation)
• Focal length
• FNumber (Aperture) if the setting is on the lens and not the camera

Consequently, DxO Optic module can't be matched automatically to images taken with such a lens, and even if we manually applied a module, the software wouldn't "know" what correction has to be applied, as the distortion, vignetting, and lens sharpness vary with focal length, FNumber, and focusing distance.