Exiv2

I am currently having trouble with the recognition of a Sigma 150-500mm f/5-6.3 lens on Canon. This lens gives a lens ID of 174 and I recently submitted a patch (issue 921) to include this lens in the list embedded in canonmn.cpp. This works for some pictures and not others.

Eviv2 was changed recently to take the maximum aperture of a lens into account for some ID numbers and looking at those pictures where the lens is recognised correctly versus those where it is not what I believe is happening is that the lens reports the maximum aperture for the focal length it is currently set to whereas the code in canonmn.cpp assumes the lens will report the maximum aperture at any focal length. Thus depending on the focal length for that picture the maximum aperture value either matches or doesn't.

Any idea how to resolve this?

BTW I have reported this as a separate issue because I suspect it will affect more than just this lens, i.e. any case where a variable aperture zoom appears in an ID conflict.