Closed circuit televisions (CCTV) are used by individuals who have various types of low vision (e.g., need for large print, poor contrast sensitivity, light sensitivity). A CCTV is a video magnifying system that uses a stand-mounted or handheld video camera to project a magnified image onto a computer monitor, television screen, or tablet. Potential school-related uses for a CCTV include reading and filling out handouts, completing arts and craft, reading books, studying images and diagrams, practicing writing, and possible viewing the board and projected materials. Other general uses are reading the mail, newspapers, magazines, bills, books, prescription bottles, writing cheques, filling out crosswords puzzles, viewing pictures, etc. Most CCTVs come with the following standard features:
- Provides an enlarged image of the material under the camera
- Variety of monitor sizes available (3 to 24 inches)
- Magnification range (2x – 75x)
- Controls for magnification, brightness, contrast
- Auto focusing
- False colours and polarity options (black text/white background, white text/black background, yellow text/blue background, etc.)
Some relatively common additional features that may be included on certain models:
- Line markers and/or masking (horizontal or vertical) to help keep track of what line is being read or block out portions of the screen and focus on one line or column at a time
- Position indicators – to help you track your place on the page
- Freeze frame capabilities
- Speech, using optical character recognition of the text to convert it to speech – this usually is paired with a highlight of the word being spoken
- Font smoothing, using optical character recognition of the text to convert it to electronic text, which can then be displayed as smooth font instead of just magnified text
- Overview mode, where the view zooms out and shows where magnification was focused on the page
- Pre-set button to allow the user to display the text in a preferred magnification and contrast
- Computer or TV connectivity
Types of CCTVs
Stationary or Desktop CCTVs
These are the “traditional” models of CCTVs. The large monitor is mounted over the camera. Stationary CCTVs have a built-in X-Y table to help move the reading material in the direction you want it to read with a locking mechanism to lock the table in place at any location. The locking feature is enabled when writing under the CCTV. This model is often chosen for prolonged reading tasks, as several words or lines of text are displayed at one time because of the monitor size. Most CCTVs have the standard features with many having the option of adding on features for an additional cost (e.g., line markers/masking, adjustable monitor arm) or purchasing a similar model with additional features (e.g., speech).
CCTVs that use Computer Monitors or Tablets (Computer Integrated)
These CCTVs connect to a computer monitor, laptop, or tablet. They offer access to the print material, the computer application, or both using a split screen function. Not all models offer the split screen feature. Some of them are made lightweight and simple to set up in order to be more portable. In addition to the standard features, some of these CCTVs will have additional features listed above as well as the following features:
- Controlled by keystrokes from your PC
- Distance mode available – for those individuals who need to switch between seeing near and distance
- Taking snapshots of images to store them onto your laptop
These CCTVs are considered portable in that you can use an existing TV monitor with them or they have a built-in portable monitor included. This model is often another option when reading is required in multiple rooms/location, e.g., in different classrooms, at home versus at the cottage. Most units are designed for easy transport, set-up, and storage (e.g., fold up to fit in a smaller space). Some but not all portable CCTVs are computer compatible. In addition to some of the standard and additional features listed above, portable CCTVs can offer additional features such as:
- Detachable cameras to use with additional arms
- Optional XY table
- Battery operated option
- Features controlled with a remote control
- Focus lock
- Rotating camera for near, distance and self-viewing
- Carrying case for easy transport
Hand-held CCTVs are often chosen for those who want access to print material while “on the go.” They can be used for reading prices tags, ingredients on food packaging, menus at a restaurant, sales receipts, etc. This type of CCTV is not chosen for lengthy reading task as the smaller display size makes this difficult to do. Each handheld unit varies with on what features they offer, but are often more basic than the larger CCTVs. Consider the following features when looking at a handheld unit:
- Magnification levels
- Viewing modes, e.g., white/black, black/white, yellow/black, etc
- Brightness adjustment
- Display size
- Size and Weight of the unit
- Freeze frame capabilities
- Handwriting feature
- Distance capabilities
- Camera indicator light
- Battery indicator
- Battery life and re-charge time
- Power saving mode
- Accessories included, e.g., AC adapter charge, batteries, carrying case with belt loop, neck/wrist strap, video cable connection to television/ computer monitor
A note on tablets and CCTVs
Some students have started using their phones and tablets for handheld CCTV functionality and distance viewing. They will either use the camera in live mode or take a picture and zoom in on the details. It is always important to consider factors, such as clarity, number of devices being used, contrast options available, ergonomics, need for writing under the device, etc. Figuring out what is the best fit may include comparing devices side by side and also breaking down what tasks and assignments require support and what this would look like on each device. While a tablet may work for some students’ needs, other students may receive additional benefit from the features of CCTVs.
Factors to consider before purchasing a CCTV
- What is the range of magnification? In what increments does it magnify?
- What display features are needed? Is it easier to read standard or reversed polarity text? Are certain colour contrasts easier to read, or is there the need for seeing true colours (such as when reading maps and pie charts)?
- Does it allow you to easily adjust brightness and contrast?
- Can the monitor height and angle be adjusted? This may help to reduce the glare reflecting off the screen from lighting in the room.
- Do you need any additional features? (e.g., line markers, masking, overview button for orientation, freeze mode, freeze focus for writing)
- Is the eye condition progressive or variable in nature (e.g., fluctuating vision, visual fatigue)? Consider the screen size, magnification range, features, and whether speech is required.
- How are the functions controlled? Are they knobs, buttons, touchpads, etc.? How is the movement controlled (i.e. manually, using a keypad/remote, or on the computer)? Does the user have the required physical abilities to operate the device? Will adapting the controls help?
- How complex are the controls? Do certain buttons or knobs have multiple functions? Does the user understand how to operate the device and to navigate with magnification without getting lost? Will any of the features help? (e.g., masking to focus the user on one line at a time)
- Is there a menu system and how easy is it to navigate and adjust settings?
- Consider the environment you will be using it (i.e., home, school, work etc.). Does it need to be lightweight and easy to pack/carry? Does it need to be wireless?
- How comfortable is the student with using this type of device?
- How is the student positioned when reading using the device?
- What is its power source? (e.g., Do you need to have a wall outlet available? Is it USB powered?) What is the battery life of the device?
- Is a large volume of reading required? Consider obtaining electronic copies of textbooks and books that are accessible to text-to-speech, which may be more appropriate for longer reading.
Computer or device compatibility
- Does it connect to a computer or TV?
- Do you have the right connections, adaptors, or wireless support (e.g., Bluetooth, wifi) to connect?
- Does it offer split screen mode (part magnified view, part computer desktop)?
- Can the CCTV be controlled by the computer (e.g., through keyboard shortcuts)?
- Can it convert text to other documents or audio files? (e.g., .doc, .PDF, .wav, .mp3, etc.)
- Has the compatibility of the CCTV with accessory equipment been taken into account? E.g., ports, operating systems, etc.
- Does it have expandable memory? Can it be connected to other storage media such as flash cards, USB memory sticks and SD (secure digital) cards
Optical character recognition and speech
- Can the text under the magnifier or from the entire document be read aloud?
- What speech options are offered? (e.g., different speech synthesizers, speed, languages)
- Can the reading display be varied? (e.g., full screen reading, single scrolling line, one word displayed at a time)
- Will the speech feedback be disruptive in the environment? Are headphones needed?
- What is the warranty available for the technology? How are repairs handled? (e.g., is there someone in your area?)
- How will you get support if you need it? (e.g., a technician in the school, a local vendor, by telephone, by email, remote access, etc.)
- What is the payment method? (e.g., purchase, lease)?
Links are provided for information purposes only. SNOW does not endorse any of the following software and hardware.
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