by Sergey Samarin
10/21/2004 | 02:22 PM
September was a fertile month for Seiko Epson Corporation as it issued another two products, Perfection 3170 and Perfection 4180, after the August release of the Perfection 2480/2580 pair. The two new scanners are targeted at amateur photographers and beginners who want professional-like quality of image digitizing. For a starter, here’s a specifications table:
Epson Perfection 3170 PHOTO
Epson Perfection 4180 PHOTO
So what’s so interesting about the specs? The distinguishing trait of the new scanners is the scan resolution. It is because of this parameter that these scanners are positioned right before the top models in the Perfection series: the 3170 model (3200dpi) becomes a relatively cheep alternative to the Perfection 3200, whereas the 4180 model (4800dpi) – to the Perfection 4870. By the way, the latter device won the prestigious EISA Award (European Imaging and Sound Association), being officially named the best European scanner of years 2004-2005!
The above-listed specifications also indicate that there the two new devices are much alike to each other, so I think they can be described together, with some reference to the top models. The scanners both perform image digitizing in a wide range of optical densities (3.4Dmax), and the high internal bit depth of the converter (48 bits) suggests a high precision of measuring the input signal. These two parameters already guarantee you scans with gorgeous halftones and shadows.
The mechanical section of the devices features the proprietary Micro Step Drive sub-scan technology that’s responsible for high-precision movements of the carriage. Thanks to that, the mechanical resolution that corresponds to the number of steps of the scan carriage is 6400ppi for the Perfection 3170 and 9600ppi for the Perfection 4180. By the way, the scan carriage in the new scanners is moving from the end of the bed towards its beginning, so the original should be placed on the glass at the end of the bed, rather than at the beginning. I also found that the acoustic noise from the mechanism was rather loud. It is even annoying with the Perfection 4180, grating on your ears at medium and high frequencies. I suppose this loudness is due to the metallic chassis that acts as a kind of resonant amplifier. The noise is louder during the pre-scan process, but diminishes when you’re scanning in a high resolution.
Package contents
The scanners come with similar sets of accessories. The user is going to find the following in the package of either of them:
Having some features of other Perfection-series scanners, the elegant sleek design of the case has accumulated the best ergonomic properties. The cases of both models are made of robust plastic; the removable lids are decorated with additional insertions. The lid of the Perfection 4180 has a latch that fixes it at 45 degrees, i.e. you can only push the lid halfway back.
The power-on button is located at the right panel, but the power source is external. This minimizes the weight of the device as well as the interference from inter-case components. By the way, to reduce the digital noise, Epson equipped the cases of the scanners with metallic screens, which proved to be a wise move, as you’ll see during the tests.
The USB port is blocked with a latch
The USB port located at the rear panel is blocked with a transportation latch – the manufacturer reminds the user that the software must be installed before you attach the scanner to the computer. A big yellow sticker above the connectors will also remind you about that as you’re unpacking the device.
Unlike top-end representatives of the Perfection family which have both USB and FireWire connectors, the 3170 and 4180 models only offer you the Hi-Speed USB 2.0 interface. By the way, to protect the connectors from damage if you put the scanner right against the wall, the manufacturer made a special jut at the rear panel.
The slide-adapter’s lamps are built into the lids of the scanners. The adapter is powered through the scanner, so you must attach a cord that tails out of the lid to the appropriate socket at the scanner’s back panel. This connector is also intended for attaching an auto-feeder unit, purchased optionally.
You receive three holders of transparent originals with the scanners
The slide-adapter is activated automatically at a driver’s request. There are three handy holders for scanning various formats: 35mm slides (4 slides), 35mm film (2 stripes, 6 frames in each), and medium-format film (2 frames). Two holders can be stored in the scanner’s lid:
Quick scan buttons populate the face panels of the scanners. Frankly speaking, I never use them myself, preferring to call the scanner’s driver from Photoshop.
Quick Start buttons
As for the software bundle, Epson still sticks to unification: all the menus and settings comply with the common standard for all Perfection series scanners. I won’t describe the software as I did this in my earlier reviews – you can refer to them to learn about the driver’s functionality. Now, let’s get to tests.
According to your feedback, my method of testing scanners is acceptable for you, although some readers ask why I don’t use resolution targets to determine the “real resolution” of the tested devices”. Well, I don’t have such targets and moreover I don’t think it is appropriate to use them. This way of testing is subjective since such evaluations are performed “by the eye”. It is more correct to examine the modulation transfer function (MTF) and measure the scanner’s optical resolution through it. This would also reveal how well the scanner’s optical system reproduces required frequencies. I’m going to add a section with such a test soon. As yet, my testing consists of the following steps:
The configuration of the testbed remains the same from test to test, so you can compare the results with those I got in my earlier reviews. The testbed:
I mentioned above that both tested models share almost identical mechanics, but have quite different mechanical resolutions and thus should differ in the scan speed. To put it roughly, the employed sub-scan technology Micro Step Drive moves the carriage of the Perfection 3170 in 6400 steps, and the carriage of the Perfection 4180 in 9600 steps. So, theoretically, the second model should be slower than the first. I checked this out in practice, performing various scan jobs and measuring the time with an ordinary stop-watch. I used the following scan resolutions: 300dpi, 600dpi, 1200dpi and 2400dpi. Here are the results:
You see my words are confirmed: the Perfection 4180 does take more time to perform a job than the Perfection 3170. Here are more numbers I didn’t include into the diagram above:
By finding the signal-to-noise ratio we can evaluate the tolerance of the scanner’s electronics to various kinds of interference. Noise can be random or correlated, and we will deal with each type of noise independently.
The graphs below show the dependence of the random noise value on the reflection power of the grayscale sectors of the KODAK IT8.7/2 Q-60R2 target.
The signal-to-noise ratio, which is the ratio of the median of a grayscale sector to the deviation, should be regarded as “bigger is better”. That is, the bigger the SNR, the higher the scanner’s noise tolerance is. The delta SNR parameter is the total of the measurements.
As you see, although the scanners have the same stuffing, the experimental data are different. I’m inclined to write this discrepancy off to the irregularity of the scanners’ lamps, though – that’s a common thing with mercury-based fluorescent lamps.
Correlated forms of noise are the most annoying – they show themselves in the scanned image as regular “patterns” (usually horizontal or vertical stripes). The predominance of such noise greatly reduces the signal-to-noise coefficient, which is calculated as the ratio of the median to the deviation. The calculated coefficients are put into the next diagram. Bigger values are better:
This section is concerned with evaluating the error in the scanners’ interpretation of the colors of the original IT8.7/2 color target with the help of a color management system. In other words, we will know the coefficient of the color distortion introduced by the scanner into the image. Below there are gamut range diagrams for opaque (reflective) and transparent (emissive) originals.
The gamut range is outlined with a triangle in the diagrams. It is a projection on the plane and shows the scanner’s palette in the visible light spectrum. Since we know the coordinates of the vertexes of the triangles, we can calculate their areas to estimate the absolute values of the ranges.
For the comparison’s sake, I also offer the squares of the triangles for the standard sRGB and Wide Gamut RGB color spaces (the former is used with the majority of monitors, and the latter is the maximum area in the CIE La*b* space).
The next diagram is constructed by calculating the difference between the colors of the original color target and its scan. Note that Color Difference values above 5.0 are discernable by most people, i.e. evident for the “average” human eye.
The closer to the X axis – the better
The diagram shows that the errors in color reproduction fall on the darkest sections of the color target, starting from the point GS17.
Finishing this review I want to offer you real scans made with the help of the reviewed scanners.
A scan of a medium-format slide made with the Epson Perfection 3170
(KODAK Ektachrome E100S film)
A scan of a medium-format slide made with the Epson Perfection 4180
(KODAK Ektachrome E100S film)
Epson Perfection 4180: a fragment of the scan in actual size
(at the scanner’s optical resolution)
I guess the results of my tests have helped you to form your own opinion about the continuators of the glorious traditions of the Perfection clan. I would like to acknowledge the creative approach of Epson’s engineering team who are always coming up with something new in their devices. The new scanners will surely be demanded by novices and professional alike. If you need a functional home machine for high-quality digitizing of standard photographs and illustrations as well as of slides and negatives, the Epson Perfection 3170/4180 might be your choice – just choose the optical resolution you’d like to have.
Highs:
Lows: