Please recompile Image Magick with support for libraw
Image Magick attempts to use ufraw to read raw images, but that package is not available on Alpine.
/mnt/library/admin/2022/2022-12-07 # identify -verbose _DSC0809.arw
identify: delegate failed `'ufraw-batch' --silent --create-id=also --out-type=png --out-depth=16 '--output=%u.png' '%i'' @ error/delegate.c/InvokeDelegate/1924.
identify: unable to open image '/tmp/magick-cor787OGvofYfRSVw873CsWOWqJeckPC.ppm': No such file or directory @ error/blob.c/OpenBlob/3569
In addition, it seems the project may have been abandoned and consequently has been removed from other package repositories like Debian.
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=931725
It seems the recommendation is to recompile packages to use libraw instead.
https://github.com/ImageMagick/ImageMagick/issues/1617#issuecomment-505529230