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pixels to ems - was RE: Relative vs. absolute units

for

From: Kevin Spruill
Date: Jan 7, 2003 3:12PM

Jules, et al...

Rough justice division reveals that by dividing #pixels by 16 you get the equivalent in ems... a little tweaking from there should handle it if/when necessary

HK

Kevin Spruill
National Library of Medicine
OCCS
<EMAIL REMOVED>
(301) 402-9708
(301) 402-0367 (fax)
www.nlm.nih.gov

>>> <EMAIL REMOVED> 01/07/03 11:18AM >>>
Despite the fact that the bytowninternet.com example you gave is quite an
eye-opener, it raises the question, how does one measure in ems or convert
from Photoshop pixels to HTML ems?

Jules

> -----Original Message-----
> From: John Foliot - bytown internet [ mailto: <EMAIL REMOVED> ]
> Sent: Friday, January 03, 2003 5:21 PM
> To: <EMAIL REMOVED>
> Cc: <EMAIL REMOVED>
> Subject: RE: Relative vs. absolute units
>
>
> Jules,
>
> Your reading is both correct and reasonable.
>
> However, remember that with the latest versions of popular
> browsers, they
> also support relative sizing for images. See:
> http://www.bytowninternet.com/examples/relative.html for
> examples of what I
> mean.
>
> While most images, when subjected to this treatment, may lose
> a fair bit of
> quality, it is an important consideration when developing
> graphics such as
> buttons or "clickable" icons. In these instances, making the
> image scale
> with the text may aid in accessibility, despite the
> degradation of image
> quality.
>
> Food for thought.
>
> JF
>
>
>
>
> > -----Original Message-----
> > From: <EMAIL REMOVED>
> > [ mailto: <EMAIL REMOVED> ]
> > Sent: Friday, January 03, 2003 3:22 PM
> > To: <EMAIL REMOVED>
> > Subject: Relative vs. absolute units
> >
> >
> > Hi:
> >
> > WCAG 1.0: Checkpoint 3.4
> >
> > "Use relative rather than absolute units in markup language
> > attribute values
> > and style sheet property values."
> >
> > I understand the purpose of using relative font sizes but WCAG 1.0
> > Checkpoint 3.4 does not make the distinction that it is
> referring to only
> > font sizes or if it is refering to any time a measurement is to
> > be used. For
> > example, for usability issues, graphics should be sized
> with height and
> > width but graphics have a "physical" dimension and should be
> > measured using
> > pixels, an absolute unit of measurement. In an instance where the
> > left cell
> > of a layout table in which the left cell is the navbar for the
> > page (and the
> > site), if the links are graphical links, then the graphics
> will have to be
> > measured using pixels and it makes sense to make that
> cell's width also
> > measured in pixels. However, I do agree that the table as a whole
> > should be
> > sized using percentage (for example 100%) so that the right
> cell with the
> > content may expand or contract as the widht of the browser window
> > dictates.
> >
> > Is this a reasonable interpretation of checkpoint 3.4?
> >
> > Jules
> >
> > ---------------------------------------------------------
> > Julian Rickards
> > Digital Publications Distribution Coordinator
> > Publications Services Section
> > Ontario Ministry of Northern Development and Mines
> > Phone: (705) 670-5608
> > Fax: (705) 670-5690
> >
> >
> > ----
> > To subscribe, unsubscribe, or view list archives,
> > visit http://www.webaim.org/discussion/
> >
> >
>
>
>
> ----
> To subscribe, unsubscribe, or view list archives,
> visit http://www.webaim.org/discussion/
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