Basically a faster, more expensive version of the Epson WorkForce DS-6500, the Epson WorkForce DS-7500 delivers all the same strong points. In particular, it offers both a 100-sheet automatic document feeder (ADF) for heavy-duty scanning by small-office standards, plus a slightly larger than letter-size flatbed for originals, like bound pages, that won't go through the ADF. Unfortunately, although it's faster than the DS-6500, it's not enough faster to make a compelling case for the difference in price.
Epson rates the DS-7500 at 40 pages per minute (ppm) and 80 images per minute (ipm) for duplex (two-sided) scanning, with one image on each side of the page. Compared with the DS-6500's rating, that translates to being a full 15 ppm and 30 ipm faster. However, the real-world difference is a lot less.
Speed ratings for scanning from an ADF are based on timing the scan itself, from the instant the first or second page starts moving into the scanner to the instant the last page lands in the output bin. The time doesn't include the lag between hitting the start button and actually starting the scan or the lag between the last page going through the scanner and the file getting written to disk.
That lag—from both before and after the actual scan—can be significant. More important, some scanners do a much better job than others of minimizing the overhead. That's why two scanners with the same rated scan speed can take significantly different amounts of time once you add the overhead in. It's also why two scanners with different ratings can be closer or further apart in speed than their ratings suggest. When I timed the DS-7500 complete with the overhead, it turned out to be only a little faster than the DS-6500. I'll come back to that issue in detail a little later.
Basics and Setup
Physically, the DS-7500 is essentially identical to the Epson DS-6500, measuring 8.5 by 19.4 by 14.1 (HWD) inches. Setup is also identical, with a USB connection as the only choice in the standard configuration. Epson also sells an optional Network Scan Module ($349.99 direct), but didn't provide one with the review unit. For my tests, I connected by USB cable to a system running Windows Vista.
Both scanners also come with the same software. And I mean literally the same. After installing each scanner on a different computer, I was able to move either scanner to either computer, and both worked without problems.
The Document Capture Pro scan utility that comes with both offers any number of useful features. It lets you send scans to various destinations (email, a printer, an FTP site, SharePoint, Evernote, or Google Docs), and it lets you save them to disk in searchable PDF (sPDF) as well as image PDF and other image formats. It also lets you add pages to or delete them from a group of already scanned pages or change the order of pages.
The only application program Epson provides is Abbyy FineReader 9.0 Sprint, for optical character recognition (OCR). However, the installation program installs Twain and WIA drivers, and ISIS drivers are available for downloading from Epson's Web site, which means you can scan with virtually any Windows program with a scan command.
Scan Speed
Like most document scanners, the DS-7500 offers a higher optical resolution than you generally need for document scanning, at 600 pixels per inch (ppi) using the ADF or 1,200 ppi when using the flatbed. The default settings, which I used for my tests, are typical for document scanners as well, at 200 ppi for Document Capture Pro and 300 ppi for FineReader. Epson's speed rating for the scanner, at 40 ppm and 80 ipm, applies to either resolution at any color setting.
For scanning to image PDF format, using our standard 25-sheet text document, I used Document Capture Pro. The speed was only 32.6 ppm for simplex (one-sided) scans, and 56.6 ipm for duplex scans.
It's not unusual for scanners in this speed range to come in much slower than their ratings on our tests. The Editors' Choice Xerox DocuMate 5445, for example, rated at 45 ppm and 90 ipm, managed only 38.5 ppm and 75.0 ipm, Part of the issue is that for any given scan program, the overhead I talked about earlier stays the same. But at faster scan speeds, the same amount of lag is a bigger percentage of the total time, which drives down the speed in ppm.
You can see the effect easily see by comparing our test results for the DS-7500 and Epson DS-6500. Despite both scanners using the same software, and both having essentially identical hardware except for the speed, the DS-7500 was slower than its rated speed, while the Epson DS-6500, did a little better than its rating, at 26.8 ppm for simplex and 50 ipm for duplex. Keep in mind, however, that the lag you'll see will depend on variables like how fast your computer is, how much memory you have, and how fast your hard drive is at saving files.
That said, at least the DS-7500 is faster in real-world use than the Epson DS-6500 for scanning to image files. That wasn't true in my tests for scanning to searchable PDF format, which is the more useful choice for most document management applications.
Scanning with Text Recognition
As with most scanners, both the DS-7500 and Epson DS-6500 take significantly more time when you add the recognition step. However, in my tests the DS-7500 added even more time than the DS-6500. In fact, it added enough extra time to wipe out the speed advantage it had for the scan itself. For scanning to sPDF format, I used FineReader to scan, recognize the text, and save the file. The DS-7500 finished the scan itself at 38 seconds, making it 10 seconds faster at that point than the Epson DS-6500. The total time, however, was a consistent 2:36 for the Epson DS-6500, but a range of 2:44 to 3:37 for the DS-7500.
The slower time for the DS-7500 seems to be a result of its scanning in color despite the software being set for grayscale. The files came out to as large as 10KB, compared with 2.5KB for the DS-6500 scans. In addition, some pages include a blue streak along one edge, which likely makes recognition harder and slows down the OCR step. Significantly, the files that had more pages with blue streaks were also the ones at the high end of the range for timing.
Epson says that the DS-7500's scanning in color shouldn't be happening and likely indicates something wrong with the particular scanner we had for testing. Unfortunately, Epson was not able to send a replacement. Assuming Epson is right however, the processing time after the scan should be the same with both scanners. If that's the case, a DS-7500 that's working properly should have a total time of 2:26, which still isn't much faster than the Epson DS-6500.
Also demanding mention is that some scanners don't add any time at all for recognizing text. That can give a slower scanner an advantage over a theoretically faster scanner. The Editors' Choice Canon imageFormula DR-2020U, in particular, offers the same speed rating as the DS-6500, but takes only 1:23 for scanning to either image PDF or sPDF format, making it faster for sPDF scans than either the DS-6500 or the DS-7500.
Very much on the plus side, the DS-7500 did will for text recognition accuracy on my tests, reading Times New Roman fonts at sizes as small as 8 points and Arial at 6 points without a mistake.
As may seem obvious, if you're considering the DS-7500, you should also take a close look at the Epson DS-6500. Less obvious is that you should look at the Canon DR-2020U as well. With its 50-sheet ADF, it's not designed for quite as heavy-duty use as the Epson scanners. Like both Epson scanners, however, it offers a flatbed as well as an ADF. If you need to scan primarily to sPDF format and don't need a 100-sheet ADF, it may be the better choice.
Between the two Epson scanners, whether the Epson WorkForce DS-7500 is worth the additional cost depends largely on how much you scan and what format you scan to. If you scan primarily to sPDF files, it's hard to see how you could justify paying more to get nearly the same scan speeds. If you only need image files, however, and depending on how much you scan, the extra cost for the Epson WorkForce DS-7500 may be worth the minor increase in speed.
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