On XP, the usual default setting is 'Standard' font smoothing. What this means is that the rasteriser applies font smoothing as specified in the font gasp table. Typically, this results in aliased text sizes at which main stems are fitted to a single pixel thickness, and greyscale antialiasing kicking in at the size at which those stems jump to two pixels. Often, greyscaling will also be turned on at very small sizes e.g. <9 ppem, for which hints are not provided. A typical text face will have gasp table settings something like this:

<9 ppem = antialiasing only
9–18 ppem = hinting only (aliased)
>19 = hinting and antialiasing

Note that this applies specifically to TrueType fonts.

I say ‘usual default’ because it is possible for an OEM distributor, such as a computer manufacturer shipping a machine with Windows pre-installed, to set different defaults.

Also IE7 and IE8 force on CT on Windows XP.

Cheers, Si

The computers I have seen have been running Firefox and Google Chrome, but I guess IE applies to the general mass.

John: I googled it before I posted and a few blogs claimed XP have font smoothing off by default, but I don’t necessary trust them. Do you have another source?

Every XP system I ever had came with Standard font smoothing on by default.

Again, one thing you need to be aware of when reading e.g. support forum questions about this is that if users are looking at typical text sizes with Standard font smoothing turned on, they're not going to see any smoothing in most cases because the typical font gasp table turns off smoothing at those sizes. This is confusing for a lot of users, who don't understand that smoothing is size specific in the Standard mode; whereas in ClearType mode it applies to all sizes.

>Does Win XP have font smoothing (not standard greyscale, neither cleartype) turned off by default?

Yes for text.

>Every computer running Win XP I've seen have had it turned off...

At most common text type sizes most XP users have aliased type by default.

>Also IE7 and IE8 force on CT on Windows XP.

Applications forcing the user into ClearType, is this regular XP or only after Service Pack upgrades?
And also, with the SP upgrades does the rendering ever change or is it always the "first" ClearType for XP users?

>Every XP system I ever had came with Standard font smoothing on by default.

But for text, there's really no difference between Standard and None to the user. Maybe that's why it's confusing.

Cheers!

But for text, there's really no difference between Standard and None to the user. Maybe that's why it's confusing.

Exactly so.

Yeah. This is really confusing. I just saw FF Tisa at text size (14 px) on the computer in question. OS: Win XP, browser: Firefox. It looked horrible. Some stems were 2 px wide, some only 1, and it had lots of black spots all over. Meanwhile Georgia/Verdana were sharp(pixelated), but didn’t have any of the wierd artifacts Tisa had. Why is that? I thought the real difference with Georgia/Verdana was the hinting, but Tisa is hinted as well isn’t it?

its likely that Tisa has hinting, but may not have x-direction hints to control the stem weights under black and white conditions. That would explain the different stroke weights.

see
http://www.microsoft.com/typography/TrueTypeHintingWhy.mspx

When I look at FF Tisa Web Pro on Typekit, it appears to be rendered in Greyscale under Firefox on Win XP, which would suggest that the GASP table is set to use greyscale at smaller sizes. There may be a difference between Tisa and Tisa Web Pro?

The site I looked at used FF Tisa Web Pro from Typekit, just to be clear about that.

>I thought the real difference with Georgia/Verdana was the hinting

Actually not, as their popularity on the Mac attests. Fortunately, Tisa will always look pretty good on the Mac at 14 regardless of what Windows does, (so far).

Unfortunately, the difference between a $20,000 hinting job and a $500 hinting job, is not likely to end up on a font name anywhere, unless we start giving radically long font names.

EPAR anyone?

Cheers!

What is the difference, David? And a typeface called “Xxx Web Pro” should IMHO work on the web.

Frank, can you tell me how your XP system is set? If you do the following

To activate ClearType in Windows XP right click on the desktop and select 'Properties', select the 'Appearance' tab and press the 'Effects…' button. Check the tick box next to the words 'Use the following method to smooth edges of screen fonts;' and select 'ClearType' from the drop down box. Close the Effects dialog by clicking Okay and click 'Apply' to complete the process.

if 'Use the following method to smooth edges of screen fonts button is not selected, you will most likely see the uneven stem widths. if you choose 'Use the following method to smooth edges of screen fonts, then choose 'standard' you will see Greyscale, and if you choose ClearType, you will see ClearType.

the uneven stem widths, is a lack of x-direction hints to control stams, so it looks like the font is not otimised for black and white.

>Frank, can you tell me how your XP system is set?

Unfortunately, we can't do that for the web in html. Can you find out why?
I mean, You can find out how Frank is Set, but that doesn't really help with "the web."

>And a typeface called “Xxx Web Pro” should IMHO work on the web.
Agreed, we'll keep the word "web" our of your font names ;)

And then there's this...

Cheers!

the fontshop website for ff tisa, is displaying prerendered bitmaps, probably generated in photoshop, hense the greyscale. you can stop scratching now, unless its nits ;-0

Who is using black and white rendering nowadays? Those who use a system that’s older than Windows XP (which came out in 2001!) or manually deactived smoothing. Do you expect that a foundry will invest thousands of $20,000 hinting jobs for prehistoric environments? Not even Microsoft ‘C’ fonts are targeted for this rendering method. Georgia and Verdana are, of course, since it was the standard when they were released.

Mike, I know how to change the settings. That’s not why I’m asking.

ok well the only answer I have then is what Ivo says above, that the cost is too high to target black and white, and thats why you are seeing the uneven stems. I think your setting, if its set to no smoothing at all on XP is unusual.

@Ivo: According to David’s post XP does have smoothing off by default at text sizes, and XP is pretty big still, isn’t it? 57.8% in March this year according to W3Schools.

I don’t expect anything. I’m just trying to figure out how to work with web fonts as a designer.

Actually, font smoothing is enabled on XP by default. It is up to the designer of the font to set the GASP table to tell the system when to enable Greyscale for a particular font. In the case of Verdana and Georgia, the GASP is set to disable greyscale at reading sizes, as John mentioned above. You can set the fonts GASP table to always render in greyscale, when standard font smoothing is enabled, if that is what you consider best.

Frank: According to David’s post XP does have smoothing off by default at text sizes

Correction: by default, XP allows the font to determine the size at which greyscale antialiasing is turned on, so while in practice this most often means that text sizes are aliased in fact it is font-specific.

could have sworn I just said that. :-!

>XP is pretty big still....57.8% in March this year...

But Simon says it's really only 20%.

...which has me Scratching My Head II.

But back in Scratching My Head I:
Verdana is as big as one can make a font, and set solid "j" just about crashes into itself, ya see.
It composes 6 lines in an inch, as any font should at 12 point on 12 points, ya see.

One could not compose 6 lines of Tisa (as these 2 websites show 12 point), in an inch. ya see.

Someone's changed the sizing somewhere? So, I can't find out what Frank means by 14 point, that's all.;)

Cheers!

I think 20% was with respect to IE6.

@David:
I’m Scratching My Head III. The website were I saw FF Tisa in use (a different website than www.typekit.com) had the text set a 14 px size. That’s really nothing to worry about though, I’m more interested in knowing if I can trust “web fonts” to look like they should, and moreover: to look like the reseller claims it does. I’ve seen three XP computers in just a couple of weeks with very different rendering than what Typekit shows.

Let’s break it down:

1. Font smoothing is either off or on in the OS (I have to count from XP and up, where it’s “on” by default). Can we get a clear answer regarding XP, something official?
2. Some users turn this off, but I guess I shouldn’t worry to much about them.
3. Some web browsers override the OS settings (Safari on Win).
4. The font has a GASP table that may disable smoothing at some sizes. Why?
5. The font might be (should be) hinted. Will these hints be used at all sizes regardless of the GASP table?
6. A selected few fonts (Verdana/Georgia) are hinted more extensively. What is the difference between this and basic hinting (other than the price tag)?

4. The font has a GASP table that may disable smoothing at some sizes. Why?

Legibility studies reliably indicate that stroke density is important to reading and that making some strokes grey instead of black undermines letter recognition. None of which should be surprising. When a stem is being represented by a single pixel width, black and white aliased rendering (presuming a well hinted producing legible bitmaps) performs better than greyscale antialiased text because it maintains stroke density. This is why the GASP table exists and why it is typically set as it is. Compare (aliased top, antialiased below):

In contrast, ClearType antialiasing does a much better job of retaining stroke density due to its colour filtering technique, and of representing the true weight of stems in the x-direction due to its subpixel rasterisation:

Which is why ClearType rendering ignores the GASP table settings and applies its anti-aliasing at all sizes.

Of course, ClearType has other issues that are evident at lower resolutions, notably colour fringing. Which is why some users will still prefer 'Standard' rendering.

5. The font might be (should be) hinted. Will these hints be used at all sizes regardless of the GASP table?

The GASP table has three settings:

antialiasing only
hinting only (aliased)
hinting and antialiasing

Generally speaking, the antialiasing only setting is used only for very small sizes, e.g. <9 ppem, or occasionally for very large sizes; that is, for sizes too small to produce legible b/w bitmaps and for sizes too large for hints to have much effect anyway.

I’m more interested in knowing if I can trust “web fonts” to look like they should...

How should they look?

I wrote ‘The GASP table has three settings’. Actually, I suppose it technically has four settings, because it is also possible to turn off both antialiasing and hinting, but I can't think of a good reason why anyone would do that.

>Of course, ClearType has other issues that are evident at lower resolutions, notably colour fringing. Which is why some users will still prefer 'Standard' rendering.

With the implication, of course, that an alternative solution to the all-or-nothing of ClearType might help many aliased users over the hump into anti-aliiasing.

>I’m more interested in knowing if I can trust “web fonts” to look like they should...

I can see “web fonts” only with great effort. And I can only speak for myself, but I know I cannot trust “web fonts” to look like they should everywhere.

Here, you read "At intermediate sizes, [which is between too small to read and too big to need,] hinting and monochrome rendering will usually produce the best appearance"

But then there is ClearType ;)

Cheers!

David: With the implication, of course, that an alternative solution to the all-or-nothing of ClearType might help many aliased users over the hump into anti-aliiasing.

I'm not convinced that's the implication. From a readability perspective, I suspect a lot of users are better off with well-hinted aliased text than they would be with any antialiasing model that reduces stroke density, and that includes e.g. Apple's Quartz rendering. ClearType is the only antialiasing technology that does a good job of maintaining stroke density. In another thread recently, you suggested at ‘to be safe, one would want a font where all the main stems have become 2-pixels-worth of the em’, but that's cheating: once one is up to that kind of weight, stroke density is guaranteed for such stems regardless of AA method, but a) I don't think setting everything in Bold is the answer to screen readability and b) with anything other than ClearType horizontal hairlines will still turn a paler shade of readable.

[There's a syntax error in your link to the gasp table spec, David: a trailing " at the end of the URL.]

There is just one way to get consistent rendering accross different plattforms, browsers and settings today: pixel fonts.

> [There's a syntax error in your link to the gasp table spec, David: a trailing " at the end of the URL.]

Fixed.

John> [There's a syntax error...

Seems to work fine to me.

> you suggested [] ‘to be safe, one would want... cheating:

You must be trying to appeal to my NE ea' and in truth on my speed to answah, meaning I'm a chetah.

But then again, there's a certain sort of humorless, raw naked forum savagery, to snipe extra-contextually — that I suggested setting everything in Bold as the answer to screen readability.

What I said on the other thread stands, as advice to the question there asked. If anyone disagrees, please do so there, as any gentleperson might.

>ClearType is the only antialiasing technology that does a good job of maintaining stroke density.

Truth? ClearType is the only antialiasing technology that does a Good to Great job in y with effort and an Average job in x with none. By Average, I mean somewhere 1/2 way in between un-hinted aliased fonts and what the next guy and I are talking about. (Quartz? just a different kind of Average with no effort in x or y.)

gferreira> There is just one way..: pixel fonts.

Well you and I, we have 3 ways for any user who chooses aliased and really means "high quality" through color and spacing both having fidelity to the basic principles of readability:
a. pixel fonts
b. fitted contours
c. uncompressed hinted TT

One does not easily cross the color barrier with bitmaps, but if you are just to serve XP users B&W bitmaps, good luck! Fitted contours I can only demonstrate (Franky), the implications have been discussed. The third alternative for XP users is what Greg Hitchcock has suggested, which implies larger fonts for All Windows Users as, if one is determined to provide quality through uncompressed TT hints to XP users in aliased mode, why not for CT users as well?

It's sort of not completely unlike Type3 vs Type1 fonts all over again with a "proprietary technique" of no particular skill barring the way to higher quality via a compression issue, of all things.

And thanks Kent! :)

Cheers.

Fitted counters?

David, I didn't mean to be ungentlemanly, nor humourlessly savage: it seemed to me that your comments in the other thread did pertain to the general issue of stroke density. I didn't read anything in this thread that suggested that what was ‘safe’ in that context -- type that jumps to 2-pixel stems at reading size -- didn't apply to this discussion too. Sorry if I misinterpreted your comments.

@Frank:
Let’s break it down:

>>Font smoothing is either off or on in the OS (I have to count from XP and up, where it’s “on” by default). Can we get a clear answer regarding XP, something official?

John touched on this at the beginning of the thread. OEMs could set the default setting on their shipping machines with Windows preinstalled, in the XP timeframe.

>>Some web browsers override the OS settings (Safari on Win).
I believe that Safari on Windows now defaults to Windows Rendering.

The font might be (should be) hinted. Will these hints be used at all sizes regardless of the GASP table?
Yes

>>A selected few fonts (Verdana/Georgia) are hinted more extensively. What is the difference between this and basic hinting (other than the price tag)?

the difference is in the details, as alway in high quality type design. Spacing is highly controlled in Verdana and Georgia, and details for example serifs in Georgia,are hinted in a consistent manner. Basic hinting may be good enought to clean up a font for screen display, but may miss out on some details that will ultimalty let the font down, some hinting control missing on a serif, or a crossbar somewhere, and this detail becomes obvious.

> Fitted counters?

Frode — Fitted contours, not counters. What David means is separate drawings for each size, making specific individual adjustments to fit the outlines (contours) to the underlying pixel grid.

Thanks Kent!

>Basic hinting may be good enought to clean up a font for screen display, but may miss out on some details that will ultimalty let the font down, some hinting control missing on a serif, or a crossbar somewhere, and this detail becomes obvious.

But beyond controlling all the serifs and crossbars, (which I consider to be basic hinting), hints for CT require more than simply writing perfect instructions. It also requires testing them against the actual scaling and rendering to see how CT has interpreted those instructions, and then fiddling to make up for this non-standard interpretation. This is new to the process.

If one looks e.g., closely at the instructions and results of GS vs CT on a 12 pixel Verdana l.c. m, the issue is clearer, perhaps. The GC rendering shows an m that's 9 pixels wide, the CT rendering is a whopping 13 pixels!? Same instructions!

Cheers!

In compatible widths ClearType the m @ 12 px is narrower as it had to match the black and white hinted width. I think you mean gridfitted Greyscale showing the m @ 9 pixels wide. In gridfit mode, the m is hinted to be narrower than the outline, to maintain symmetry @ 12px = m is 9 pixels in total width from left stem to right, with a 3 pixel white space for interior, left and right. If you disable hinting and just show Greyscale, you will see the m is wider. the Greyscale mode you are referring to, which is hinted, will never be seen at this size as the GASP will disable Greyscale, and only show the black and white bitmap.

Si! But the point is that the answer to the question:

> Will these hints be used at all sizes regardless of the GASP table?

...is usually no.

ClearType makes up it's own "mind" according to patented secrets, not our instructions.

Cheers!

>Si!

Mike? David?