does lowering resolution always causes lower quality text?

I was reading the review on Z61m, and the author has mentioned that because of high resolution, texts and icons are small and if resolution is lowered, text gets blurry. Is it always the same with lowering the resolution, so anyone should choose a screen with the highest possible resolution as the one he/she desires to use normally?

 

That is correct.
Since a LCD/TFT has fixed pixels any resolution that doesn't evenly divide with the resolution the LCD/TFT has will be blurry.

If you think about it it's quite easy to understand why.
Small text often have the width of one pixel. Imagine that youre lowering the resolution from say 1920x1200 to 1680x1050 every line that should be one pixel wide would be about 1,14 (1200/1050) pixels wide.
And how do you display 1.14 pixels?
So the screen will have to do the best it can and sometimes use one pixel and sometimes use two. That makes text blurry and uneven.

However you can just cut the horizontal and vertical resolution in half and get away with it. 1920x1200 would be 960x600. Every pixel on the 960x600 resolution would represent by 4 pixels on the screen.
That would work but 960x600 isn't much and I for one wouldn't stand it.

I hear that Vista has scrapped the pixel-based GUI (atleast in Aero I guess(?)) and that might improve this but I don't know for sure.

 

LCDs run best in whatever there native resolution is. For example mine runs at 1680 x 1050. If I lower the resolution to someting like 1200 x 800, the whole picture isn't as clear (blurry), but it is certainly redable. Keep in mind you can also change your font sizes to 96dpi or 120 dpi. If you are looking at buying a notebook, go to the store and see the different resolutions in person, and when you buy one, get one with a native resolutoin that most closely matches what you likes the best. Then you won't have any problems.

 

I used to believe that LCD displays looked best when used at their native resolution. However, I went through this issue recently with a friend who received a 1680 x 1050 display when he was expecting a 1280 x 800 (the manufacturer had just changed the product) and found the text too small to easily read. The font size setting in the Windows display properties does not change everything.

The first thing we did was to install the Omega driver which supported a much better range of resolutions than the ATI driver. We then tried using resolutions such as 1440 x 900 and 1360 x 850 in order to increase the size and experimented with font smoothing (two options - normal and Clear Type). The font smoothing works by putting pixels with intermediate brightness around the characters. I find that on my own display which is only 1280 x 800 the font smoothing reduces readability because of reduced contrast.

My conclusion was that with font smoothing enabled, high resolution displays can look good at a lower resolution. Lines also looked better. I will now be considering getting a higher resolution display when I next upgrade.

Hope this helps,

John

 

The best bet is to keep your resolution matched to your native LCD resolution. When you use a lower resolution, the graphics chipset is forced to either display the lower resolution screen with black bars around the edge, or to 'scale' the lower resolution screen to the higher resolution screen. This scaling is typically done using a bilinear filtering algorithm (or even worse, no filtering at all) and that's what causes the 'smudged' or blurred effect; in addition, while this kind of filtering works alright for lines and straight edges, it typically distorts curves and circles displayed on the screen because of the mathematics involved. Also, if you don't pick the a lower resolution that has the same aspect ratio as the LCD, you'll get a distorted screen with icons that are too wide (or narrow).

So if the text and graphics are too small, first enable the large font sizes, and then also enable the large icon sizes as well. That should help considerably. You can also individually adjust font sizes for different parts of the interface in the display properties if just using large fonts isn't good enough. Remember that ClearType has lots of different anti-aliasing styles so even if you don't find the default ClearType to work well you can go into the Control Panel and change it to suit your tastes. If you enable ClearType / anti-aliasing AND also are using a lower than native resolution, you are essentially antialiasing things twice over and reducing the edge contrast of the letters even more. It's up to you to decide whether it's more readable, but I think it would make the letters less well defined.

If you can't get it to fit your needs, you might need a lower resolution LCD screen. In my opinion, however, using a lower resolution than native on an LCD screen is a last resort option. The one area you might trade off in is if you are trying to get better performance out of a game since high resolutions are difficult to run with adequate performance in many games, especially laptop chipsets.

 

My favorite resolution on 17" desktop CRT is 1024*768, so should i get one notebook with XGA? Where does SXGA may be necessary, eg games or special applications ?

 

Definitely.
SXGA+ is never "necessary", but it does make images look better.

 

I allows you to see more of the page. If you are happy with 1024x768 thats what you should get.

 

TY all, i will definitely go for XGA, I was afraid that may be some applications necassarily need higher resolutions, but if it is only about reducing the size to see more on a page, it is not what i am after.

 

You get sharper text and images with sxga+, but there is absolutely nothing wrong with XGA. Most laptops have XGA (or wide XGA).