Epson Perfection 1640SU Photo Scanner
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Introduction
Recently I upgraded the computer I use for photo work from an old, creaky, 300MHz Pentium to a new, spiffy 950MHz Athlon with boatloads of memory. I also moved from Win98 to Win2k, and as a result, I ran into troubles with the ancient scsi card that supported my even more ancient and creaky HP ScanJet 4c scanner.
Faced with either buying a new scsi card or buying a new scanner, I decided to go ahead and replace the scanner. After some dithering, I decided on the Epson Perfection 1640SU scanner, primarily because it seemed to offer enough resolution (1600 pixels/inch) with a 4x5 transparency adapter. The old scanjet 4c also had a transparency adapter, but it was not really acceptable because of noise in the scans from the flickering of the transparency adaptor.
The one thing I've lost is the ability to scan prints 14 inches long; the ScanJet 4c was a legal sized scanner.
Installation
There are things wrong with USB, but for me, installation is not among them. Every time I install new hardware, I cringe in the expectation that things will break and it will be a hair tearing, mind boggling experience.
But installing the Epson 1640SU was a cakewalk. I unboxed the scanner, put it on the cabinet where it lives, plugged in the power, and followed the directions given by Epson for USB installation, and in less than five minutes was happily scanning away.
1640SU Photo scanner with
transparency adapter in place
Hardware
Although one of the complaints leveled at the 1640SU in reviews on the web is that it's larger than other cheap USB scanners, I don't find it to be particularly large, especially compared to the behemoth ScanJet 4c it replaced.
It seems well made. It comes with a power cord, a USB cable which was just barely long enough to reach the six feet or so to the computer, and a transparency adaptor which fits onto the flatbed and plugs into the back of the scanner for power.
Transparency adapter with lid up
The transparency adaptor covers the entire scanner bed, but centers the 4"x5" transparency area on the bed. It comes with negative holders for 35mm slides, 35mm filmstrips, 120 film (with what appears to be a 56mm x 83mm window, which is sort of weird), and a 4x5 holder.
Film holders, clockwise from upper left:
4x5, 120, 35mm, 35mm slide
The 35mm film carriers and the 120 film carrier seem to be reasonably well made. The 4x5 holder is considerably more cheesy in construction, and it's probably the lamest part of the whole shebang. In addition to the somewhat flimsy construction, the 4x5 carrier has an opening that measures 93mm x 113mm, just enough smaller than the image area on a 4x5 negative to be annoying. I'll probably end up either making a better carrier or modifying this one.
Software
It comes with a boatload of software, much of which I'll never use. Included are both Photoshop 5.0LE, Photodeluxe 4.0, Textbridge OCR software, and a bunch of applets from Epson to do things like turn the scanner into a copy machine, etc.
Out of curiosity, I installed the TextBridge OCR software and found, rather to my surprise, that it does an excellent job.
Since I use the full scale PhotoShop, the PhotoShop LE and PhotoDeluxe software is worthless to me.
The twain scanning driver from Epson is pretty good - it has curve adjustment, lets you set the highlight and lowlight both manually and with an eyedropper, and gives you a preview of the scan. Lasersoft offer a version of their Silverfast software for this scanner's brother, the 1200, but apparently not yet for the 1640SU. In the meantime, it seems that the Epson driver is adequate for most uses.
Performance
Based on the performance of the (fairly expensive when I bought it new years ago) HP ScanJet 4c, I had only modest expectations for the Epson 1640SU Photo.
It's exceeded all of them. Clearly, there's been a world of improvement in the intervening years. I paid $400 US for the Epson, and I'm tremendously pleased with the scans I get from it, especially when I consider the price.
Scanning at 1600 pixels/inch is not particularly speedy; I presume that it would be faster if I used the SCSI interface instead of the USB interface. Scanning a 4x5 transparency at 1600 ppi and 42 bit color, it takes 5.75 minutes to complete the scan. I've no idea how this compares to other scanners, but it seems ok to me.
But speed is not really a critical issue, and what I most wanted was a way to scan 4x5 negatives for web display, and 1600 ppi is considerably more resolution than I need for that.
Scanner manufacturers are renowned for their inflated Dmax claims. Epson claims the 1640SU Photo is capable of a Dmax of 3.2. To test this claim, I scanned a 4x5 Stouffer step wedge, which ranges in density from near zero (filmbase + fog for whatever the wedge base is) upwards in steps of 0.1 logD for a total of 31 steps and a maximum density of 3.0 logD.
After some experience with the scanner controls, I can now scan the step wedge and get a value of 0% on step 1 and a value of 100% on step 31 by carefully tweaking the controls on the scanner twain interface, I can get a scan where 29 steps are clearly discernable, with obvious tonal differences between steps.
Disappointingly, the noise level in the densest part of the step wedge is high enough to be visible. The following image is from step 27 of the step wedge, scanned as a negative. Note the noise - less dense steps scan with considerably less. Now, note - this is from a step with a density of about 2.8 logD - pretty dense.
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| Noise level from scanning
step 27 of Stouffer wedge (negative image not inverted) |
So perhaps for color transparencies, a drum scan remains the ultimate - but for B&W negatives, the density range of this scanner is more than adequate, even for pretty bulletproof negatives.
For those who are interested, I've scanned the 4x5 TMX negatives from my recent work on the Pacific Coast, adjusted the images with Photoshop, and the results are available for viewing here.
As a comparison, I took a Velvia transparency which had been drum scanned (by www.nancyscans.com) and scanned it on the 1640SU Photo. The following two images are (heavily) cropped portions of the image, which was scanned at 1600 pixels per inch on the 1640SU. Note that the scale of the scans is slightly different, and the color balance is radically different. I've not attempted to adjust the color balance of the 1640 scan.
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| portion of drum scan from www.nancyscans.com |
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| portion of 1640SU photo scan of same transparency |
Now, it's perfectly possible that I'm doing something senseless that's reducing the sharpness of the 1640SU scan, but it first blush, it seems to me that the sharpness is not even in the same league as the drum scan.
My tentative conclusion is that the scanner is terrific for what I want to use it for - inexpensive scans targeted at web display. For high resolution scans where the target is to print the results on an ink-jet printer, it looks like either work needs to be done to learn how to extract better sharpness from the 1640 (better film holders, accurate registration to match focus, etc.) or else you preview scan things on the 1640SU Photo and then send the winner images out to be drumscanned.