Comment 4 for bug 587326

My manual lenses are not properly detected by my camera. Overwriting the tag "Exif_Photo_LensModel" using the Image Inspector works fine, but phatch returns an error:

Error 0:Can not apply action Write Tag on image 'DSC08918.ARW' in folder:
/home/martin/tmp/phatch

Format ARW does not support overwriting "Exif_Photo_LensModel".

Action:{'fields': {'Tag (Exif, Iptc)': u'Exif_Photo_LensModel',
            'Value': u'Takumar 50mm F1.4',
            '__enabled__': 'yes'},
 'label': 'Write Tag'}

Traceback (most recent call last):
  File "/usr/share/phatch/phatch/core/api.py", line 614, in apply_action_to_photo
    photo = action.apply(photo, read_only_settings, cache)
  File "/usr/share/phatch/phatch/actions/write_tag.py", line 49, in apply
    info[tag] = value
  File "/usr/share/phatch/phatch/core/pil.py", line 324, in __setitem__
    self.assert_writable(tag)
  File "/usr/share/phatch/phatch/core/pil.py", line 429, in assert_writable
    % {'format': self['format'], 'tag': tag})
NotWritableTagError: Format ARW does not support overwriting "Exif_Photo_LensModel".
*

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content of phatch-file:

{'actions': [{'fields': {'Tag (Exif, Iptc)': u'Exif_Photo_LensModel',
                         'Value': u'Takumar 50mm F1.4',
                         '__enabled__': 'yes'},
              'label': 'Write Tag'},
             {'fields': {'File Name': u'<filename>',
                         'In': u'<folder>/phatch',
                         '__enabled__': 'yes'},
              'label': 'Save Tags'}],
 'description': '',
 'version': '0.2.7'}