RE: Screen size...resolution...zoom

Hi Jonathan,

Yes, we’re agreeing – the HTML inner width (or width of HTML element in the inspector) is the key measure.

On a Mac that’s the same as the window width at 100%, but you need to be careful on windows.

Cheers,

-Alastair

From: Jonathan Avila [mailto:jon.avila@levelaccess.com]
Sent: 26 July 2017 17:51
To: Alastair Campbell <acampbell@nomensa.com>
Cc: public-low-vision-a11y-tf <public-low-vision-a11y-tf@w3.org>
Subject: RE: Screen size...resolution...zoom

Alistair, I was checking the innerWidth property and as I said when I used scaling the innerWidth at x resolution was different at 100% zoom depending on the scale used.  What property should I use if innerWidth is not the best?

My point is that resolution may not be useful to record but instead innerWidth or whatever viewport measure should be used or recorded – if that is what you are saying then I agree!

Jonathan


From: Alastair Campbell [mailto:acampbell@nomensa.com]
Sent: Tuesday, July 25, 2017 5:25 PM
To: Jonathan Avila
Cc: public-low-vision-a11y-tf
Subject: RE: Screen size...resolution...zoom

Hi Jonathan,

The key measure for this when zooming is the viewport width.

I’m on Windows (at home), with a standard display and high-res display.

If I use the web-dev toolbar to resize to 1280px wide, the viewport with (width of the HTML element) is 1225px. I think that’s because the laptop display is at 250% and Windows gets rather confused and gives me HUGE scrollbars!

On the mac the scrollbar is not included in the view (it appears over the top when scrolling), so the window width = viewport width at 100% there.

If I move the chrome window onto the high-res laptop display, the viewport size is still 1225px even though the display is at 250%, the OS zooming is abstracted away from the browser rendering point of view.

So the bottom line is to check the width of the HTML element in the inspector.

Cheers,

-Alastair


From: Jonathan Avila [mailto:jon.avila@levelaccess.com]
Sent: 25 July 2017 20:18
To: Jonathan Avila <jon.avila@levelaccess.com<mailto:jon.avila@levelaccess.com>>; public-low-vision-a11y-tf <public-low-vision-a11y-tf@w3.org<mailto:public-low-vision-a11y-tf@w3.org>>
Subject: RE: Screen size...resolution...zoom

I ran a quick test on my Windows 10 machine and set the resolution to 1024x768 and set the “change the size of text and apps and other items” to 125%.  I then when into my browser and checked.  The viewport width was reported at 913 and the scale factor was 1.25 and the zoom level was 100%.  So if we collect data on being able to zoom to 400% we need to consider recording these factors in our data collection.

Jonathan

Jonathan Avila
Chief Accessibility Officer
Level Access, inc. (formerly SSB BART Group, inc.)
(703) 637-8957
Jon.avila@levelaccess.com<mailto:Jon.avila@levelaccess.com>
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The information contained in this transmission may be attorney privileged and/or confidential information intended for the use of the individual or entity named above. If the reader of this message is not the intended recipient, you are hereby notified that any use, dissemination, distribution or copying of this communication is strictly prohibited.

From: Jonathan Avila [mailto:jon.avila@levelaccess.com]
Sent: Wednesday, June 21, 2017 8:27 PM
To: public-low-vision-a11y-tf <public-low-vision-a11y-tf@w3.org<mailto:public-low-vision-a11y-tf@w3.org>>
Subject: RE: Screen size...resolution...zoom

Thanks Jim.  I added some comments to the article regarding other factors such as MS Windows scale factor, viewport width, and font size specified on webpages.  This is a critical task that we need to get data on – however we must collect all of the relevant data for the conclusions to be most useful.

Best Regards,

Jonathan

Jonathan Avila
Chief Accessibility Officer
SSB BART Group (soon to be Level Access)
(703) 637-8957
Jon.avila@ssbbartgroup.com<mailto:Jon.avila@ssbbartgroup.com>
Looking to boost your accessibility knowledge? Check out our free webinars!<http://www.ssbbartgroup.com/webinars/>
The information contained in this transmission may be attorney privileged and/or confidential information intended for the use of the individual or entity named above. If the reader of this message is not the intended recipient, you are hereby notified that any use, dissemination, distribution or copying of this communication is strictly prohibited.

From: Jim Allan [mailto:jimallan@tsbvi.edu]
Sent: Tuesday, June 20, 2017 4:18 PM
To: public-low-vision-a11y-tf <public-low-vision-a11y-tf@w3.org<mailto:public-low-vision-a11y-tf@w3.org>>
Subject: Screen size...resolution...zoom

DATA!
http://sp1ral.com/2017/06/screen-size-resolution-and-zoom-oh-my/