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Re: Accessible color and contrast for projected presentations

for

From: Whitney Quesenbery
Date: Sep 2, 2014 6:36PM

Back in the day, one of the conferences where I presented used to send out
very strict guidelines for presentation templates. They wanted large text
and high contrast. They preferred black text on a light background for
consistency among speakers.

They weren't (strictly speaking) accessibility advocates, but they pointed
out they they ran a professional updating conference with fairly long
rooms, so people at the back were 20 rows of seats (maybe 60 feet) away
from the screen. And, people wanted to take notes which, back before the
days of tablets, meant writing on paper. On the handouts they provided. So
there was light in the room.

My point is that there is every reason in the world to think about the
context in which your slides will be shown. And if you plan to make a
presentation, I assume you want people in the room to be able to see what
you project. Unless, of course, it's just wallpaper to make a design behind
you, in which case none of this matters. But if you want people to see
what's on your slides:

- High contrast (I'd suggest at least AAA, if not 10:1)

- Large text - the guideline for signage is to make your text 1.75 inches
larger for every 50 feet of viewing distance (1.75" at 50' to 5.25" at 150'
to 8.75" at 300')

- No distracting backgrounds behind the slides

and you might think about

- most important information in the top half of the slide to take into
account rooms with flat floors, where heads block the bottom half.




On Tue, Sep 2, 2014 at 7:24 PM, Sean Curtis < <EMAIL REMOVED> > wrote:

> Thanks all for the information. I'll be recommending we improve contrast to
> at least AAA levels, and that we try to move away from Keynote/Powerpoint
> in favour of an accessible, HTML based solution. Using HTML will allow
> people to follow along on their own device, thus allowing them to benefit
> from whatever assistive technologies they have set up for themselves.
>
> Cheers,
>
> Sean Curtis
>
>
> On Wed, Sep 3, 2014 at 4:07 AM, Olaf Drümmer < <EMAIL REMOVED> > wrote:
>
> > Hi,
> >
> > On 31 Aug 2014, at 23:18, Sean Curtis < <EMAIL REMOVED> > wrote:
> >
> > > In addition to web accessibility we're researching the accessibility of
> > > slide decks for conference presentations for low vision users. We have
> a
> > > gap in our knowledge here, and would really appreciate any input.
> >
> > I think trying to solve issues in the setup of and apparatus used for a
> > presentation by optimising a file is a complete waste of efforts, in many
> > less than perfect setups there is no possibility to succeed.
> >
> > A major building block of access and assistive technologies is that a
> user
> > can adjust the presentation to her needs. There is no way a slide
> > presentation presented through a video projector can be adjusted to an
> > individual's person needs without disregarding the needs of others.
> >
> > To me it seems to be a much better approach to use alternative options in
> > the presentation setup. One such option could be to use ad hoc screen
> > sharing in some fashion. Options to do this are VNC (screen sharing over
> > the LAN network, available in a couple of freeware options), web meeting
> > or webinar solutions (GoToMeeting, WebEx, or the free of charge Google
> > Hangout On Air, etc.). Low vision users for example have essentially the
> > same display quality as if they viewed the slides on their computer or
> > tablet, they could for example zoom in to enlarge portions of the
> > page/slide.
> >
> > Olaf
> >
> > > > > > > >
> > > >