This type of aid also allows for the widest field of view for reading. A low vision professional can make recommendations for magnifiers for specific tasks based upon the vision of the individual. Cost is a major drawback. CCTV also is less portable than glasses or magnifiers. Despite these drawbacks, it does allow the view to adjust various parameters such as size, contrast, and brightness to the persons needs.
Reverse polarity allows the letters to appear light on a dark background, to reduce glare.
CCTV is quite helpful in the workplace or school. Non-optical aids include a variety of devices such as black felt tip pens, dark linked paper, writing guides, filters, or lamps. Writing guides are templates with open areas along the lines to keep writing aligned. Many individuals discover techniques very helpful for themselves and others. Training in their use is available.