HP ScanJet 4470

48-bit scanner with transparency adapter

Product: HP ScanJet 4470 color scanner
From: Hewlett-Packard
Street Price: C$299 (at this writing, the company offers a US$50 mail-in rebate program.)
Pros: Excellent image quality. Front panel copy controls.
Cons:  Scanned images tend to favour red; HP warns of compatibility glitches with Windows Me.

Compatibility
We tested this scanner primarily under Windows XP. It is not directly supported by the built-in Windows XP drivers and, indeed, double-clicking the ScanJet 4470 icon that appears in the "My Computer" window produced an error dialog; older scanners, such as the HP ScanJet 5200c invoke the XP Camera and Scanner Wizard or your choice of scanning programs when launched this way.

We also conformed some glitches under Windows Me with an HP technician, who suggested downgrading to Windows 98 as a solution. Interestingly, the scanner does work when invoked from the icon that appears in the "My Computer" window under Windows Me. At least on our test computer, it was only the "scan to..." function that didn't seem to work. Worse, we couldn't even uninstall the PrecisionScan software to try installing it again. Reverting back to Windows 98 resulted in the resolution of both of these error conditions, which HP says don't affect all Windows Me users.

Software and Hardware Overview
The package includes the HP PrecisionScan Pro 3.1 software we've mentioned in previous ScanJet reviews, plus HP's scan-to-web utility.

With a front panel layout similar to that of the ScanJet 5470 (reviewed elsewhere in this section), the 4470 is a sleek unit with several buttons on the front panel for invoking various functions: scan and send an image via email, scan and print, etc. The software bundle also includes a utility allowing the scanner and a printer to do double duty as a photocopier for up to 99 copies.

A transparency adapter comes standard with the unit, capable of handling a standard strip of negatives. The package includes a non-flexible black plastic mask that fits on the letter-size (8.5" x 12") flatbed, into which the smaller transparency adapter fits. This is a much better design than we've seen on most other scanners, which typically use a flimsy piece of black plastic which never seems to lay flat or stay put. When installed, and the appropriate slides or negatives option is selected from the PrecisionScan menu, the adapter provides a top-lit light source, allowing slides or negatives to be scanned at up to 2400 pixels per inch.

Scan Quality
Our first test was to compare the scan quality of a photo that we'd previously scanned on an HP ScanJet 5200. The results in a word were excellent. There was simply no comparison. We immediately reached the inescapable conclusion that our old scanner was crap, and must be replaced ASAP.

In fact, with a fair amount of work, we were able to correct the 5200c's output to closely resemble the colour produced by the 4470 default settings.  An unsharp mask was applied to both images. The 4470's output is otherwise unretouched. Look closely at the sample images (5200c and 4470) and you can clearly see the much greater amount of noise introduced into the picture (particularly in the red areas) by our efforts.

It's worth mentioning that the 5200c wasn't always that bad; its colour accuracy and dynamic range seem to have deteriorated over the past couple years. In fact, this appears to be a common phenomenon with all the scanners we've owned: their light sources seem to have a useful life of only two or three years, after which the results just aren't up to par any more. At any rate, the histograms shown here tell the tale. The 4470 demonstrates a vastly superior dynamic range -- primarily a credit to its 48-bit colour capture circuitry. The 30-bit 5200c, on the other hand, suffers from an inability to depict the darker details of our test image.

The software can save in a variety of other formats, including GIF, JPEG, FlashPix, BMP, TIFF, Compressed TIF, etc. The software can also converted printed words to text using an included version of I.R.I.S. OCR (optical character recognition) technology, allowing you to avoid retyping texts.

Colour fidelity of scanned images was good, but not particularly accurate. The green hues of an original studio portrait with a slightly greenish cast overall were automatically balanced in favour of the red end of the spectrum. This isn't as bad as it sounds. Actually, the resulting scan looked better than the original, in terms of skin tones and colour brightness. We could detect no unpleasant artifacts. Image sharpness was superb. We did not choose to invoke the PresicionScan software's automatic sharpening feature (we prefer to manually apply an "unsharp mask" filter in a program such as Photoshop), although this feature, along with descreening and basic colour correction, resizing, rotating and cropping features are all provided.

Conclusion
Overall, we liked the ScanJet 4700 a lot more than we expected to. Its image quality is excellent, although you might need to perform minor colour adjustments if absolute colour accuracy is a priority.

For Further Reading:

• Review: HP ScanJet 7400
• Review: HP ScanJet 5470