Prevent imagess from being listed in the media module

Hey guys,

I created a domain model that has a property to hold an image.

     * @var \Neos\Media\Domain\Model\Image
     * @ORM\OneToOne(orphanRemoval=true, cascade={"all"})
     * @ORM\Column(nullable=true)
    protected $photo;

I use a relation to Image because I need to render the image later in different sizes. Before I related to PersistentResource but I could not find an easy way to scale those images while rendering.

My problem:
Those images now appear in the Neos Media Browser where I expected only Images/Assets for content purposes. Is there a way to prevent those images from my model to be shown?