Tech review | Portable printers

Computers have gotten smaller and smaller over the years. You can slip into a briefcase a fully functional 2-pound laptop that's still big enough for touch typing. And if you don't need to touch type, you can get a heck of a lot of computing power in a cellphone kept in your shirt pocket.

But what to do for printing when you're on the road?

Sure, some hotels have office centers where you can plug your device into a printer. But what about hotels that don't have such centers? And what about when you're in the airport, or working from your car?

Printers, like computers, have gotten smaller in recent years. Yes, there are some obvious limitations. After all, if you're going to print on a piece of paper that's 8.5 inches wide and 11 inches long, it's going to be difficult to design a device that can fit in your shirt pocket. Still, when I sought out the best mobile printers, I was surprised by how much vendors have been able to fit into small footprints.

I took a look at three market-leading offerings and found that each has something to offer. The trade-offs are not surprising — the smallest printers lack some features, and the more features you need, the more you can expect to pay. But one of these portable printers is likely to fit the needs of any mobile user.

Pentax PocketJet: Remember those pencil cases you used to carry to school? That's about the size of the Pentax PocketJet 3. If your priority is portability and you need only black-and-white printing, you won't find a more portable device that the PocketJet.

More specifically, the PocketJet measures 10.04 inches wide by 2.17 inches deep by 1.18 inches tall. And the unit weighs in at only 1.12 pounds. You won't even notice the PocketJet if you throw it into your briefcase, suitcase or the back seat of your car.

You'll need a tad more room for the AC adapter, of course. But if you've charged the printer's battery before you hit the road you should be able to print around 100 pages without plugging in.

The downside? First, instead of using space-consuming inkjet cartridges, the PocketJet employs a thermal printing process. That means you have to use special thermal printing paper.

Also, don't expect blazing speeds. A typical page of text will take about 20 seconds to print, and graphics will slow things down significantly.

You won't be able to print in color and, finally, this tiny device doesn't include a sheet feeder. That means you'll either have to feed sheets in manually or use a roll of continuous paper.

The printer can be adjusted to any of 11 density settings, which will affect the speed of printing. If all you need is a quick reference copy, just set a lighter density.

The PocketJet also provides both USB and IrDA ports. There's even a Bluetooth option, though you'll have to make up your mind if you want this before you buy. You can't add Bluetooth once you've purchased your device.

The PocketJet 3, which has a resolution of 200 dpi, has a street price of about $275. The PocketJet 3 Plus, which delivers a resolution of 300 dpi, carries a street price of about $480.

Canon Pixma iP100: Yes, Canon's Pixma iP100 is several times as big as the Pentax PocketJet. Measuring 12.7 by 2.4 by 7.2 inches, the iP100 might fit it into your briefcase, but there won't be much room for much else.

Still, at 4.4 pounds, the device won't break your shoulder strap. And this little printer, which has long been a favorite of traveling professionals, offers a lot of extras in a compact package.

For starters, it's a full-color inkjet printer that can crank out 14 pages of text per minute.

The iP100 also boasts relatively high resolutions. When printing in black alone, you can get 600 by 600 dpi, and when printing in color the printer delivers 9800 by 2400 dpi. The printer, in short, is fully capable of printing quality photographs. You can even directly connect PictBridge-compatible cameras or storage chips to the iP100 for printing.

The iP100 does require a bit more setup than the other printers. You not only have to install ink cartridges, you also have to install the print head itself. And some users may not be comfortable with all the warnings about what to touch and what not to touch.

There's also a procedure you're expected to go through to align the printer head before using the printer. It wouldn't work for me, but it didn't seem to be necessary. The device huffed and puffed and eventually got down to work. And after that it was almost as quick to print as the HP H470.

Finally, the iP100 doesn't come standard with a battery pack or a Bluetooth adapter, though these are available as extra-cost accessories.

The bottom line: Canon delivers a very portable all-purpose printer at a bargain price of only $249.99 list.

HP OfficeJet H470: If you want to keep your options open for printing on the road, the HP OfficeJet H470wbt is the printer for you.

The H470 is about the same size as the Canon Pixma. It's 13.4 by 6.45 by 3.25 inches footprint is a little taller than the Pixma, but it's also a less deep. And the device also weighs in comparably at 4.2 pounds (4.6 pounds with battery).

Like the Pixma, the H470 is a full-color inkjet printer that's can print in black and white at up to 1200 dpi and in color at 4800 by 1200 dpi. The H470 is faster than the other printers, cranking out text pages at a zippy 22 pages per minute.

But where the H470 really shines is in its connectivity. Like the other printers I tested, the H470 supports USB connections.

Bluetooth is available as an option. Like the Canon Pixma, the H470 offers direct connectivity for PictBridge-compatible devices.

Only the H470, however, supports connections via 802.11 wireless. And only the H470 supports Secure Digital (SD) card and Multimedia card (MMC) input.

The only glitch I encountered using the H470 was that it was a challenge getting the inkjet cartridges into their receptacles. But once I figured out the right angles, setup went smoothly.

Like the Canon Pixma, the OfficeJet H470 can handle standard paper as well as photo paper, and you can put up to 50 pages in the device for automatic sheet feeding.

List prices for the H470 range from $249 to $314, depending upon connectivity options included.

Patrick Marshall writes the weekly Q&A column in Personal Technology.