What is the best way to change the labels of the ImageGallery. I need to customise it like so:

ImageGalleryAlbum.php

public function getCMSFields_forPopup()
	{
		return new FieldSet(
			new TextField('AlbumName', _t('ImageGalleryAlbum.ALBUMTITLE','Artist Name')),
			new TextareaField('Description', _t('ImageGalleryAlbum.DESCRIPTION','Artist Statement')),
			new ImageField('CoverImage',_t('ImageGalleryAlbum.COVERIMAGE','Artist Main Image'))
		);
	}

And also change all "album' references to "artist" the above does not seem to have any effect?

Thanks

---------------
EDIT

public function getCMSFields_forPopup()
	{
		return new FieldSet(
			new TextField('AlbumName', _t('ImageGalleryAlbum.ARTISTNAME','Artist Name')),
			new TextareaField('Description', _t('ImageGalleryAlbum.ARTISTSTATEMENT','Artist Statement')),
			new ImageField('CoverImage',_t('ImageGalleryAlbum.ARTISTMAINIMAGE','Artist Main Image'))
		);
	}

I'm pretty sure the cleanest way to do this would have been to override the lang file.

$lang[your_Locale]['ImageGalleryAlbum']['ALBUMTITLE'] = "My Label";