Assessment and Instructional Strategies for Using Video Magnifiers

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Assessment and Instructional Strategies for Using
Video Magnifiers

• Presented by
• Ike Presley
• American Foundation for the Blind
• 100 Peachtree St., Suite 620
• Atlanta, GA 30303
• 404-525-2303
• presley_at_afb.net
• www.afb.org

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Assessment

• User factors
• Visual
• Physical
• Cognitive
• Working environment
• Physical space
• Tasks to be completed
• Near
• Distance

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Assessment

• User factors
• Visual
• Clinical low vision evaluation
• Magnification needed
• Viewing distance
• Polarity preference
• Physical
• Manipulating controls
• Cognitive

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Assessment

• Working environment
• Physical space
• How much room is available?
• Will user be working with a computer?
• Computer compatible system
• Tasks to be completed
• Near
• Reading
• Writing
• Distance

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Assessment

• Which model is best?
• Desktop models
• Wider range of magnification
• Reading writing
• Transportable
• Friction brake Margin stops
• Flex-arm camera models
• Great for distance
• Portability

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Assessment

• Which model is best?
• Portable models
• Hand-held camera
• Require physical coordination
• Flex-arm camera
• Need to add X/Y table for extensive reading
• Head mounted displays
• Appearance
• Fatigue
• Stand alone units - pocket models
• Not practical for extended reading

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Assessment

• Which model is best?
• Digital camera models
• No X/Y table needed
• Hands free reading
• Transportable
• Difficulty with variations in background
• Promise of speech
• Expense

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Setting Up the Viewing Environment

• Glare and Reflections
• Away from perpendicular to windows
• Lighting
• Overhead
• Use of hoods
• Provide ample room for system and needed materials

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Setting Up the Viewing Environment

• Table Chair Issues (Ergonomics)
• Viewing height
• Viewing angle
• Viewing distance
• Visual fatigue

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Basic Instruction - Getting the Viewer Hooked

• Determine viewer interests prior to instruction
• Sports
• Fashion
• Crosswords
• National events
• Local events

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Basic Instruction

• Acquire simple line drawings with some details
• Boardmaker and other clip art
• Lock X/Y table
• Friction brake
• Margin stops

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Basic Instruction

• Preset image at smallest magnification
• Ask viewer to identify image
• Slowly increase size until viewer can identify
  image and details
• Encourage viewer to maintain comfortable viewing
  distance, 10-15 inches

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Basic Instruction

• Present other drawings with more detail
• Photographs
• Objects
• Allow viewer to adjust
• Magnification
• Focus

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Basic Instruction

• Brightness and contrast
• Demonstrate effect on image
• Have user manipulate controls with
• Line drawing
• Photographs
• Objects
• Point out need to adjust controls
• Simple and complex line drawings
• Photographs, etc.

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Basic Instruction

• Color and polarity
• Demonstrate effect on image
• Allow user to manipulate controls
• Point out need to adjust controls for different
  images being viewed
• line drawing, photographs, objects
• Note that viewer may prefer different settings
  for
• line drawing, photographs, objects

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Basic Instruction

• Avoid use of presets in beginning
• Turn system off
• Instruct viewer in use of
• Power switch
• Magnification
• Focus
• Change magnification focus
• Ask viewer to adjust

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Developing Tracking Skills

• Horizontal tracking
• Left to right
• One row
• Lock friction brake
• Adjust margin stops
• Start with simple activities
• Horizontal table movement only
• Match pattern/picture on same row

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Reading Strategies

• General Tips
• Tips on How to Use and Buy CCTVs
• by Brian Smith
• Texas School f/t Blind and VI website
• www.tsbvi.edu/technology/cctv-tips.htm
• Golden Rule
• Make it big enough to view comfortably
• Tendency to over magnify or under magnify

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Reading Strategies

• General Tips
• Place viewing materials on X/Y table
• Exception
• Small items
• Checkbooks
• Business cards
• Initially use both hands to manipulate X/Y table

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Reading Strategies

• General Tips
• Use finger to locate something to view
• Place finger on beginning of location you want to
  see
• Go find your finger in the image

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Reading Strategies

• General Tips
• Use friction brake
• Controls up and down movement
• Reduces nausea / sea sickness
• Use margin stops
• Controls left and right movement
• Helps user locate end of line
• Helps user return to beginning of next line

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Reading Strategies

• General Tips
• Most frequent complaint "sea sick"
• Suggestions from Karen McCall
• The Box Came Today, Now What Do I Do? A Resource
  for CCTV Assessment and Training)
• Look at edge of monitor when returning to
  beginning of line
• Read sentence look at painting on wall

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Reading Strategies

• General Tips
• Read sentences that fit on one line.
• Set margin stops and friction brake
• At first use
• Double
• Triple
• or Greater
• spacing between lines

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Reading Strategies

• General Tips
• Reading graphical information
• Adjusting magnification
• Adjusting color

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Writing Strategies

• Working in two planes
• Eye-hand coordination
• Locking the X/Y table
• Keep working area small
• Within range of camera
• Reduce movement

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Writing Strategies

• Use some of the reading activities
• Eye-hand coordination boosters
• Tracing stencils and templates
• Mazes
• Matching
• Word searches
• Crossword puzzles
• Writing with lined and unlined paper
• Completing forms

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Follow-up

• Check optional settings
• Create activities to improve speed and accuracy
• Practice
• Practice
• Practice

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References

• Ann Arbor Tracking Program, (1988) Letter
  Tracking Sentence Tracking Symbol/Letter
  Tracking Word Tracking, Novato, CA Academic
  Therapy Publications.
• DAndrea, Frances Mary and Farrenkopf, Carol,
  (2000) Looking to Learn promoting literacy for
  students with low vision. New York, NY AFB
  Press.
• Frostig, Marianne, Pictures and Patterns

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References

• Lev, L. Jay, EdD, (1988) Eye-Hand Coordination
  Boosters, Novato, CA Academic Therapy
  Publications.
• Lund, R. Watson, G. R. (1997). The CCTV BOOK
  Habilitation and rehabilitation with closed
  circuit television systems. Synsforum ans.
  Frolund Norway.

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References

• McCall, Karen, (2001) The Box Came Today, Now
  What Do I Do? A Resource for CCTV Assessment and
  Training, www.iprimus.ca/martha/cctv- manual.htm

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Thank you for attending

• For additional information on
• video magnifiers
• go to
• www.afb.org/assistivetech