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iPhones or iPads Colour Vision Settings

This “tutorial” is written to assist people having difficulty operating an iPhone or iPad due to vision impairment, or have some colour vision deficiency, or Colour Blindness.


As described by the National Eye Institute, see


“Most of us share a common color vision sensory experience. Some people, however, have a color vision deficiency, which means their perception of colors is different from what most of us see. The most severe forms of these deficiencies are referred to as color blindness. People with color blindness aren’t aware of differences among colors that are obvious to the rest of us. People who don’t have the more severe types of color blindness may not even be aware of their condition unless they’re tested in a clinic or laboratory.

There are three main kinds of color blindness, based on photopigment defects in the three different kinds of cones that respond to blue, green, and red light. Red-green color blindness is the most common, followed by blue-yellow color blindness…”


If your device is an iPhone 6, (September 2014) or later, and enabled with iOS10, Apple introduced a new Accessibility setting called “Display Accommodations”, which allows the individual user to set filters that best meet the way they see the colour of the world,  and include a simple Colour Blind test.


Apple may have chosen the wrong colour scheme for some of the most popular actions, as light blue may be difficult for people with colour vision deficiency. (Tritanopia), particularly if on a grey backgroundMail headings 1.png

 Mail Headings 2.png


As an iPhone and iPad user, you must follow through these tips yourself, do not get someone else to do it for you as you must adjust each setting in accordance with what you see through

Your own eyes.


Step Tap Settings> then Step 3, tap General>


Screen Shot 2017-04-15 at 9.42.53 pm.png         Screen Shot 2017-04-15 at 9.42.24 pm.png


Step 3. press “Accessibility", then Step 4. press “Bold Text” and slide the button to "ON"


Accessibility.png     Bold Text.png


Tapping the “Bold Text” Button to ON will restart your phone, so this process may take a couple of minutes. But take the time to toggle this switch On and Off a Couple of times and compare Readability of a selection of Texts.


Leave this "Bold Text" button set to which Ever is better for YOU.  For example, compare the Icons at the top of Mail with "Bold Text" ON, with the same icons shown above before Step 1, where "Bold Text" was OFF


Continue Bold text.png           Bold Mail icons.png


Step 5. Tap to Change “Larger Text” To “On”, then Step 6. Tap to change

“Larger Accessibility Sizes” to “On” and Drag the slider to increase or decrease the text size.


You may find some Apps present a confused Screen if the text is too large and you may need to reduce

Text Size


Also tap "Button Shapes". This changes things like the "< General" below to "General" in a grey box. Many with low level Colour Vision Disability find the blue text in the grey button box more difficult.



Larger Text.png   Larger text 2.png


Step 7. Tap “Accessibility” to return to this screen. Turn ON “Reduce White Point” and move slider to a

preferred level.


Step 8. Turn on “Colour Filters” in these two spots. The colored pencils should start as Red on the left, yellow, green, blue, pink to purple and brown on the right. The 3 dots below the pencils indicate that there are 2 more pictures, so swipe the pencils to the left


Reduce White Point.png     Colour Filters.png.



Step 9. Swiping the pencils to the second screen will bring up a colour chart. These colours are adjusted for each filter, so you will move back and forward across these last two screens repeatedly for each Filter.


Step 10 - Select a Filter and swipe to the next screen. Those familiar with colour blindness tests will be familiar with the patterns. 


Slide the “INTENSITY” bar until You are able to best see the vertical lines (5 on iPhone, 9 on an iPad) with the best uniformity


Select “< Back” and repeat this process with all other filters.


Ypu will need to spend some time repeating the process here. For those with Colour Vision Deficiency, the screenshot on the right is green at the top, fading to a yellow/lime green at the bottom. This matrix of "honeycomb" is crossed by 5  vertical lines which should look pinkish at the top and purpleish at the bottom. Slide the "INTENSITY" bar till you can best see those vertical shades. On some filters there is a "Hue" slider out off the bottom of the screen, Move this slider ttoo to get the best vision.


Colour Filters 2.png        Colour Filters 3.png


“Invert Colours” in step 7 changes text from black on white to white on black, but it also changes photos and other graphics from positives to negatives and I found this little benefit.


Turning on Grey Scale and adjusting the filters may assist those with total colour blindness.


In certain apps try Invert Colours which makes things a higher contrast.  Get there by Settings> General > Accessibility> Invert Colour. If this setting improves access for you, assign this function to the Accessibility Shortcut which is right down the bottom of the Accessibility Settings page. This means you can switch between regular view and inverted view by triple clicking the Home button. This action needs to be performed very quickly but you can slow the need for speed via  the Home Button setting, also in Accessibility.


The Zoom function may make the big difference to accessing low contrast directional buttons on many apps and websites.


The accessibility feature of the app or site doesn't matter when using Zoom.  Turn Zoom on in the Accessibility Settings and then switch between regular view and zoomed view with a three finger double tap. Move the visible area of the screen by dragging it with three fingers, particularly left to right. You can often scroll down the page with one finger.


Increase magnification with a three finger double tap and hold then drag those three fingers up the screen. Repeat with dragging down to decrease magnification.


On the downside, some actions you try to perform while Zoom is on won't work. For example, searching in the Google app. As I read down through the results, I cannot select the desired result without turning Zoom off. 


Try these functions. Using Zoom becomes quite cumbersome but it is a fabulous tool if the frustration doesn't dominate the experience. If you are affected by low vision as well as the colour recognition thing and ofter a big bold magnified view of the screen  create a new awareness of what the page offers.


The irony of the design of these devices is that the settings meant to assist people who are “Challenged”, in some way are always the most challenging gestures in themselves, i.e. triple tap or 3 finger swipe type gestures may be way off the capability scale?


Other useful instructions can be found here:


The (US) Hadley Institute for the Blind and Visually Impaired has many tips on using the vision accessibility features in iOS.





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May 2017
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