Amazon's Kindle 2 is slimmer, faster and has longer battery life than its predecessor. But the newly launched e-book reader falls short when it comes to how well it displays text, say some users.

"When you read a lot of text on the screen, the contrast on the text drops as the font size gets smaller, which is the exact opposite of what the reader wants," says Ted Inoue, a Kindle 2 owner from Pennsylvania who has extensively analyzed the issue.

It's a problem that didn't exist for the first generation of Kindle owners. Kindle 2 has font smoothing algorithms and its screen offers more levels of gray in order to better render text and pictures. But the changes have backfired by making text more difficult to read at smaller sizes. The problem seems especially acute for older users.

Kindle 2 owners are discussing the issue on Amazon's forums (about 480 messages have been posted in the thread) and have called for Amazon to offer a quick fix to the problem. It's vexing enough for some to have returned their Kindle 2 devices to Amazon. Others have downgraded, by exchanging their Kindle 2 units for the earlier model.

Amazon released the first generation of the Kindle e-book reader in 2007 and offered a refreshed version in February this year. One of the major improvements has been that Kindle 2 has 16 shades of gray "for clear text and even crisper images," compared to the four shades that the earlier version had.

The changes are proving to be particularly problematic to Kindle 2's users who don't have 20/20 vision. While the font size threshold varies, most complaints have been around the smallest three font sizes available on the device. Kindle 2 offers a single default typeface and users cannot change it.

"The new basic font on the Kindle 2 is thinner and not as dark as the K1," says Andrys Basten, a Berkeley, California-based web programmer who also has a Kindle-focused blog. "Its like writing with a fine point pen versus a darker point pen." Basten owns both generations of the Kindle.

Kindle 2's improved gray scale renders photographs and illustrations better than the old version, but it is a problem when translating text that was originally designed to be in color. (See here for a quick explanation on how the gray scale works.)

"With the Kindle 1, all people would get is black shading for text that was originally in color," says Basten. "Now there is increased gradation, which makes text lighter, and some people have trouble seeing it."

Kindle 2's display is supplied by E Ink, which also produces the "electronic ink" displays used in most other e-book readers. E Ink did not respond to a request for a comment.

Then there are the font smoothing algorithms. Without those algorithms, pixels along the edge of a letter would have typically been rendered as black. Instead, they are now available in several shades of gray, as shown in the photographs above. "In conventional backlit displays that works well," Inoue says. "But on a reflective screen like Kindle's, you are just losing contrast rather than enhancing the image."

The algorithms do produce smoother lines but they do not take into account the human psychology of perception, says Inoue. "Most people don't have perfect vision," he says. "What I find is that anything that degrades the contrast is going to make it blurrier."

Amazon says the disgruntled customers' gripes are not reflective of how most users feel. "A few customers have said they prefer Kindle 1 with less shades of gray, but for the overwhelming majority it’s the opposite – they enjoy the smoother text and crisper images on Kindle 2," says Andrew Herdener, director of communications for Amazon in a statement, without offering any other details.

Still, Inoue and other Kindle 2 users say there are a few easy fixes that Amazon can make to keep everyone happy. One is to render text below a certain font size without applying any

anti-aliasing to it, says Inoue. "This is not a perfect solution, as people with extremely sharp vision will notice the blockiness and may find it objectionable," he says. "However, for the majority of the population, the pixelation that occurs will be blurred out by the eye, making the fonts appear bold and smooth."

Another solution could be to offer a way to make the fonts at lowest three sizes bold. And if nothing else works, suggest Inoue, add a darker skin to the Kindle to offset its all-white body. The darker skin helps create an illusion of increased contrast.

Some users have gone a step ahead. Andrei Pushkin, a Kindle 2 owner has created a fonts hack that replaces the default Kindle 2 fonts with ones that support a wider range of Unicode characters, including, for example, Cyrillic.

That's a step too far for Basten, who says she would rather wait for an official update.

"I see the relative lightness of the new font but it doesn't bother me," she says. "I am not complaining much because I really like my Kindle."

Do you see a difference between your Kindle 1 and Kindle 2 screens? E-mail us side-by-side photographs of the screen or post them to the Gadget Lab Flickr group.

See also:

Wired Review of Amazon Kindle 2

Kindle Readers Ignite Protest Over E-Book Prices

*Photos: Ted Inoue's photos of Kindle 2 display before and after the font is made bold

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