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Michael Rowley
04-12-2005, 03:03 PM
I've only just tried switching Clear Type on in Windows XP, and it seems to produce a noticeable improvement on my CRT screen. As Microsoft doesn't claim much improvement on CRTs, as against those other devices (which almost everyone else seems to have), I'm wondering whether the apparent improvement is just my imagination. Is there anyone else too poor to possess a superduper screen on the forum? If so, what is your experience of ClearType?

Stephen Owades
04-12-2005, 06:22 PM
I've only just tried switching Clear Type on in Windows XP, and it seems to produce a noticeable improvement on my CRT screen. As Microsoft doesn't claim much improvement on CRTs, as against those other devices (which almost everyone else seems to have), I'm wondering whether the apparent improvement is just my imagination. Is there anyone else too poor to possess a superduper screen on the forum? If so, what is your experience of ClearType?
Steve Gibson of Gibson Research has a very interesting web site discussing the concepts behind ClearType: start here (http://www.grc.com/cleartype.htm) and follow the links--the Q&A discusses the very issue you've raised. In short, ClearType produces an anti-aliasing effect when used with a CRT monitor; on an LCD it does far more and looks far better.

As for the "superduper screen" issue, anyone with a laptop has an LCD display that can benefit from ClearType. If the LCD is big and coarse (as many desktop screens are), the side effects of ClearType may be bothersome, but with a small high-res screen the effect is wonderful. On my IBM ThinkPad with 15" 1600x1200 display, black-on-white text looks almost like print on paper.

Apparently Microsoft is improving ClearType in the forthcoming Longhorn operating system. See Ian Griffiths' blog (http://www.interact-sw.co.uk/iangblog/2004/07/22/longhorncleartype) for the results of some experiments he's done with the developer release of Longhorn.

Michael Rowley
04-13-2005, 10:53 AM
Stephen:

ClearType produces an anti-aliasing effect when used with a CRT monitor

The improvement is probably not a figment of my imagination then; but as I had everything switched on for font smoothing in Windows, I take it that the ClearType system works better.

Actually the Microsoft exposition of clearer type is better than Gibson's, and, of course, it's more up to date (the Gibson page is dated 2003).

A small digression: why call the phenomenon of jagged outlines 'aliasing'? It's not English, or even an approximation to English. (Formosan? Korean?)

Stephen Owades
04-13-2005, 11:23 PM
Stephen:

ClearType produces an anti-aliasing effect when used with a CRT monitor

The improvement is probably not a figment of my imagination then; but as I had everything switched on for font smoothing in Windows, I take it that the ClearType system works better.

Actually the Microsoft exposition of clearer type is better than Gibson's, and, of course, it's more up to date (the Gibson page is dated 2003).

A small digression: why call the phenomenon of jagged outlines 'aliasing'? It's not English, or even an approximation to English. (Formosan? Korean?)
I first encountered the terms "aliasing" and "anti-aliasing" in the realm of digital audio. In digital recording (as in CD), an audio signal is sampled at discrete intervals, converted to digital values, stored, then replayed as a series of stepped voltages corresponding to the original samples. Any incoming signal whose frequency is above half the sampling rate (called the Nyquist frequency) produces a series of samples that are indistinguishable from those from a frequency reflected around the Nyquist frequency; with a CD sampling rate of 44.1kHz, an incoming tone at 40kHz will produce the same samples as one of 4.1kHz. And when those samples are played back, you will hear an "alias" of the original frequency, in this example a tone at 4.1kHz. In order to prevent such aliases, the incoming audio must be low-pass filtered to eliminate information above the Nyquist frequency, using an "anti-aliasing filter." A similar filter is used on the output of the playback device, to keep all the analog output below the Nyquist frequency, since aliases "reflect upward" as well as down.

The same general principle, of spurious information resulting from discrete sampling of continuous material, applies to digitized images, and I presume that's why the same term is used. Smoothing the edges of a letterform or other shape by inserting grey pixels is a form of low-pass filtering, and has a similar effect--it reduces or eliminates the spurious high-frequency information (the "jaggies") in the image.

Michael Rowley
04-14-2005, 10:29 AM
Stephen:

The same general principle . . . applies to digitized images

I had read that the term 'aliasing' comes from sound recording, and although the term is derived unacceptably it is connected legitimately to 'alias'. But the jaggies aren't at all spurious: they come from trying to reproduce an image with little squares or dots. I imagine that the digital information about the images, although at discrete intervals, would apppear sufficiently accurate, so it's only the relatively coarse screens that we use today that give trouble.

Thanks.

Gerry Kowarsky
04-16-2005, 12:48 PM
I noticed a distinct improvement in type quality on my CRT when my company moved from Win200 to WinXP.

Michael Rowley
04-16-2005, 02:33 PM
Gerry:

a distinct improvement in type quality on my CRT

It seems as though we do get a definite improvement, though I wasn't expecting any.

Stephen Owades
04-16-2005, 08:57 PM
I noticed a distinct improvement in type quality on my CRT when my company moved from Win200 to WinXP.
ClearType isn't turned on in Windows XP by default, for some reason. You have to seek it out in the Display control panel; use Microsoft's ClearType tuner web site (http://www.microsoft.com/typography/cleartype/tuner/Step1.aspx), which also allows you to set Cleartype for the best results on your own display (the order of colored sub-pixels affects how Cleartype should operate); or download the ClearType Tuner PowerToy (http://www.microsoft.com/typography/ClearTypePowerToy.mspx), which also includes the ability to tune ClearType settings.

Michael Rowley
04-17-2005, 05:47 AM
Stephen:

ClearType isn't turned on in Windows XP by default

Possibly there's some drawback as well as an advantage: have you heard of one?

Stephen Owades
04-17-2005, 04:49 PM
Stephen:

ClearType isn't turned on in Windows XP by default

Possibly there's some drawback as well as an advantage: have you heard of one?
I presume that using ClearType imposes some additional burden on the resources of the computer, either the CPU or the graphics card or both. And "most" computers shipped with CRTs rather than LCD displays when WinXP was first introduced, making the "off" mode a logical choice.

There's also the "blurriness" question. Some people profess to find ClearType, or any anti-aliased type for that matter, blurry, and claim that they find it fatiguing to look at. In my opinion, ClearType works best on high-resolution (pixels-per-inch) displays, and while I don't like looking at low-res screens in general I can understand why people who use them might find ClearType more of a drawback than an advantage overall.

Michael Rowley
04-18-2005, 06:28 AM
Stephen:

Some people profess to find ClearType, or any anti-aliased type for that matter, blurry

Well, I don't but it's a matter of choice. As you may know, computers are normally sold 'complete', i.e. with keyboard, monitor, and mouse, in the UK, at least to individuals, and for some time they've been advertised with LCD-monitors, not CRTs. I think in future OSs from Microsoft, the default will be 'ClearType ON'.

Gerry Kowarsky
04-18-2005, 08:40 AM
ClearType was turned on in my company's basic build, most likely because most of our new monitors are flat panels. I'm one of the few with a CRT because I preferred keeping a 21 inch CRT to getting a 17 inch flat panel. I do see ClearType's full effects on an LCD when I am using my laptop's built-in display.

Do you happen to know if it's true that rotating an LCD panel has a negative impact on ClearType?

donmcc
04-18-2005, 12:28 PM
I tried turning ClearType on for my XP systems last week and after three days turned it off. I suspect it is a matter of being used to the sharper non-AA'd (is that a double negative) text.

Don McCahill

Michael Rowley
04-18-2005, 12:46 PM
Don:

I suspect it is a matter of being used to the sharper non-AA'd

It does make a difference if you tune the ClearType (from the Microsoft typography site or using the PowerToy). But perhaps you're one of those people with very good visual acuity still that's not deceived by the 'anti-aliasing' trick.

Stephen Owades
04-18-2005, 09:00 PM
ClearType was turned on in my company's basic build, most likely because most of our new monitors are flat panels. I'm one of the few with a CRT because I preferred keeping a 21 inch CRT to getting a 17 inch flat panel. I do see ClearType's full effects on an LCD when I am using my laptop's built-in display.

Do you happen to know if it's true that rotating an LCD panel has a negative impact on ClearType?
One reason that ClearType works is the fortuitous way in which most LCD displays are built--with the colored sub-pixels dividing each pixel into three vertical slices. This allows the colors--which are, in effect, "independently addressable" elements--to be used to adjust the thickness of vertical strokes, and the smoothness of near-vertical elements (particularly the vertical strokes in italic characters), in 1/3-pixel increments. The reason I said this is fortuitous is that it's those vertical and near-vertical elements that most need fine adjustments for good type appearance.

If you rotate the LCD to "portrait mode" so that the sub-pixels are horizontal, the trick wouldn't work as well even if the display system were aware that the sub-pixels are now horizontal instead of vertical. And I suspect that it wouldn't be aware of this, and that keeping ClearType on with a rotated display would yield seriously degraded type.

My Dell Axim X5 PDA, running the Mobile Windows OS, has the option of enabling ClearType, and I think it really makes a big improvement in the user experience. This device, like most PDAs, has a portrait-mode screen, but its sub-pixels are oriented the right way for ClearType to work. In fact, I spent several hours at a Comdex show peering closely at PDA displays before choosing the Dell, since many of the competing units had horizontally-oriented sub-pixels and wouldn't work properly with ClearType.

donmcc
04-19-2005, 10:49 AM
Oh I see the anti-aliasing, it just seems to bolden the type a bit, and make it more difficult to read. But I am very conservative (with my computer). After all, I am using XP in Win95 emulation view. Kids seem to love stuff that is different ... oldsters like me like things the way we are used to them.

JVegVT
04-19-2005, 06:35 PM
>> I am using XP in Win95 emulation view >>

You mean Classic view? Nothing unusual about preferring that. Many people (including me) find the new XP view to be garish.

I didn't care for ClearType when I was using a CRT with XP. With an LCD, which I now use, and on my laptop I think ClearType makes a big difference for the better.
--Judy M.

BobRoosth
04-19-2005, 10:38 PM
I tried turning ClearType on for my XP systems last week and after three days turned it off. I suspect it is a matter of being used to the sharper non-AA'd (is that a double negative) text.

Don McCahill

I could not agree more. Every time I turn it on, I find text to blurry. Drives me nuts. I just tried it with the monitor (19" crt, 1600x1200). I'd rather have sharp/crisp text. CT might reproduce the outlines of fancy fonts better, but when I need to verify how a font will look, I just zoom in so there are plenty of pixels to render the edges.

Michael Rowley
04-20-2005, 01:57 PM
Don:

I am using XP in Win95 emulation view

So do I (I think: is it the 'classic' view?). And if so, I must be more conservative than you, because I used Windows (for Groups) 3.11 before I changed to Windows 2000. I thought that Windows 95 etc. was much to dodgy, though I nearly installed NT 4.5.

I find ClearType improves the clarity somewhat, even on a CRT. It must be a personal thing.

tphinney
04-22-2005, 06:07 PM
Do you happen to know if it's true that rotating an LCD panel has a negative impact on ClearType?

Yes. Rotating the panel 90 degrees is essentially equivalent to viewing the text on a CRT instead on an LCD.

T

tphinney
04-22-2005, 06:10 PM
Although there is some extra computing overhead, the only reason not to turn ClearType (or Adobe's equivalent) on by default is if you are one of the relatively small percentage (5%?) of people who perceive the color fringing really strongly. Or if you just hate anti-aliasing in the first place.

Most people using CRTs find ClearType (or our stuff) not particularly better or worse. But as it's a huge benefit for LCDs, and doesn't hurt CRTs, it might as well be on by default.

Cheers,

T

fhaber
04-23-2005, 03:13 PM
I'm with Stephen0. I only use ClearType on the latest fine-pitch panels. On a 14-15" straight XGA panel, I'll take no antialiasing any day, even though it tends to the spindly with Microsoft's system fonts.

I have limited Mac experience, but Apple always seemed to handle the "virtual inch" screenfont-size better. I don't fully understand this, but then I don't understand the Mac PDF/semivector philosophy of their recent machines much at all (and would like to).

Heck, there are still boatloads of PC apps that overflow dialogues and pulldowns if you choose "large fonts." This is inexcusable in 2005.

And I have a couple of multipurpose industrial LCD panels with DVI inputs that don't use the standard pixel order. ClearType is kinda ludicruous with these.

And then there's the odd 21" Sony Artisan whose focus is still on the button. I like the older (equicolor, monochrome) antialiasing here.

And if you're a real fossil (holds up hand). and do lots of work in grey type on a black/blue background (console windows), it all breaks down even more. I still find the fonts produced by the DOS TSR UltraVision (9x14 versions of IBM's monospaced DOS/terminal fonts) the most legible ever, for extended viewing. Each to his own.

Eventually, as my eyes become totally rheumy with age, this will become the Thomistic exercise it already threatens to be. (How many non-square pixels can a blind man put on the head of a standard pin, at STP, etc. etc.)

Michael Rowley
04-24-2005, 05:34 AM
And I have a couple of multipurpose industrial LCD panels with DVI inputs that don't use the standard pixel order

The Microsoft ClearType tuning program does cater for non-standard arrangement of LCDs, i.e. those without the common RGB order.