by Sergey Samarin
05/11/2006 | 09:26 AM
In September 2005 Epson quietly (at least for me) introduced its new scanner Perfection 4490 Photo which was supposed to update the series of scanners targeted at photo amateurs and advanced users.
It is especially for such people that the company equipped the scanner with a hardware dust and scratches removal technology called Digital ICE for Film which had been earlier available in the top-end Perfection 4990 model (for details see our article called EPSON Perfection 4990 Scanner: Dйjа vu?).
The Perfection 4490 comes to the American market in Photo and Office versions, the Office one featuring an automatic document feeder (ADF). The ADF is an optional component in the version for the European market. As usual, let’s first read through the official specs of the scanner.
So, this model can digitize images at a maximum optical resolution of 4800dpi and a color depth of 48 bits. Specifically for scanning negatives, the optical density is 3.4Dmax and the included holders can be used with 35mm film and slides as well as medium-format films. Mostly because there is an office version of the scanner, its declared reliability is higher than that of other Perfection series models at 36,000 movement cycles of the scanning carriage. You are going to learn some more details about the Perfection 4490 in the next section of the review.
Like all other scanners in the Perfection series, this model comes in an Epson-style package that contains the following:
The case of the Epson Perfection 4490 is made of robust silvery plastic with decorative inserts. As usual, all of the scanner’s connectors are located at its back panel: a USB socket for connecting to a computer, a connector for the slide-adapter (or the optional ADF device), and a power connector.
The new scanner is covered all around with stickers that remind you to unblock the transportation locks before you first turn it on. There are two such locks here. One is on the device’s lid and blocks the drive mechanism of the slide-adapter’s lamp. The other lock blocks the scanning carriage and is located at the back panel near the connectors. When closed, the main lock also blocks the USB connector so you just can’t use the scanner without unlocking it.
A reflective screen must be taken out of the scanner’s lid to digitize transparent originals. Then you put the originals into the special holders and then place the holder on the scanner’s bed. Two holders are included with the device.
A Power On/Off switch is located on the left of the side panel. To minimize the effects of electromagnetic interference, the power adapter is external.
The Perfection 4490 is quite an easy-to-use device. It has four quick launch buttons on its face panel which start up the scanning program with presets to send the scanned image to the printer, via e-mail or save as a PDF file.
The next section is about the scanner’s software. Tests will follow after that.
Epson’s unified software pack comes with the scanner on one CD. The other CD contains Adobe’s Photoshop Elements. You need to install the exclusive scanner management software prior to connecting the device to the computer – the yellow stickers on the scanner’s transportation locks remind you about that. It’s easy to install the software – you shouldn’t have any troubles at all. Besides the scanner driver (required), the installer will also suggest that you install from a number of service programs (the OCR program Fine Reader among them).
The driver’s control panel doesn’t change in functionality or interface from one scanner model to another, so I don’t think it’s necessary to describe the driver’s elements yet another time.
As before, the Epson Scan program offers three scan modes: Full Auto, Home and Professional (Mode). The user can manually select the desired scanning mode depending on his/her qualification. The interface of the Epson Scan program in Professional and Home modes consists of two parts: a basic settings window and a preview window.
In fact, you can scan images from Photoshop in a simpler way – by invoking the driver via Windows Image Acquisition (WIA). The scan window will look like this then:
If necessary, you can adjust the image by changing the position of the brightness and contrast sliders.
But of course all the fine-tuning options are only available in Professional mode.
At the very bottom of the scan program window, between the Preview and Scan buttons, there is a Configuration button that gives you access to all the basic settings. As the following screenshot shows, this window is divided in four sections:
The Epson Perfection 4490 is equipped with a hardware dust removal technology called Digital ICE. You can use it when digitizing transparent originals (the corresponding options become available in the driver window as soon as you select the appropriate type of the original).
Digital ICE has two modes: Quality and Speed. As you can guess, the former mode is for getting a better-quality result while the latter is faster (see the Tests section). By the way, previous scanner models that supported Digital ICE did give you the choice between Speed and Quality. The Perfection 4490 also supports Dust Removal technology which is a software alternative to Digital ICE.
Unfortunately, neither technology works with reflective originals – the appropriate menu options become disabled.
Like in every other model of the series, Color Restoration technology can be turned on in the Perfection 4490. It restores natural colors to scans of old photographs.
In the next section we’ll see how well the scanner performs in practical tests.
I tested the scanner using our traditional methodology for an in-depth examination of all the operating properties of the device like scanning speed, noise tolerance, resolution, etc. The configuration of the testbed remains the same, so you can compare the results with those we got in our earlier reviews.
Configuration of the testbed:
First I’ll check the speed characteristics of the Epson Perfection 4490.
There are different ways to measure the speed of a scanner, but I think the right one is to measure the time it takes to perform a scanning task which can be much longer than the time the scanning carriage takes to get back to its initial position. So, I start my stopwatch the moment I click on the Scan button and stop it the moment the scanned image is fully transferred into the control program, i.e. into the image editor.
I used two originals of standard form-factors: a 10x15cm (4x6”) photograph and a 35mm slide. The samples were digitized at 24-bit color depth and in 600dpi, 1200dpi, 2400dpi and 4800dpi modes. The results are presented in the following diagram:
The scanner took a total of 20 minutes to complete the task at its optical resolution (4800dpi), although the driver had transferred the image in 10 minutes. The rest of the time the computer was busy writing the huge temporary file on the hard drive.
In order to check how fast Digital ICE technology is in this scanner, I digitized a standard 35mm slide in three modes: at the standard settings, with Digital ICE enabled in Quality mode and with Digital ICE enabled in Speed mode. You can see there’s a small difference between Quality and Speed mode at low scan resolutions, but considerable at high resolutions.
You can use these numbers to compare the speed characteristics of the Perfection 4490 with those of other scanner models we have tested on our site.
I dwelt upon the nature of digital noise in my earlier reviews. In brief, the signal-to-noise ratio which is measured in this test is indicative of the tolerance of the scanner’s electronics to various kinds of interference. The image noise can be random or correlated. I’ll deal with each type of noise independently.
The diagram below shows the dependence of the amount of random noise 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.
Correlated forms of noise are the most annoying – they show themselves as image “patterns” (horizontal or vertical stripes, usually). 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:
By the way, now that this section is all about noise, I’d want to acknowledge here that the Epson Perfection 4490 is very quiet at work.
The resolution is the accepted criterion for dividing scanners into different categories. This parameter is indeed an important characteristic of any scanner. The real optical resolution depends not only on the number of elements in the CCD array but on the entire optical system.
It is possible to check how well the scanner digitizes an original with numerous tiny details. For such tests special patterns with alternating black and white lines are employed. The spatial frequency parameter of a pattern is expressed in the number of line pairs per inch (lppi). A pattern looks like that:
Applied Image QA-69-P-RM Test Target
There are five patterns here with a different spatial frequency (30, 70, 95, 140 and 180lppi) and I will scan them at the maximum optical resolution of the scanner (4800dpi).
The image contrast tends to degenerate at higher spatial frequencies – this tendency is characterized with modulation. By measuring the modulation for the five patterns of the target it is possible to see the dependence between the image contrast and the spatial frequency of the patterns. I publish the results of two other scanners for the sake of comparison.
Next, I will calculate the modulation transfer function (MTF), which is the frequency characteristic of the scanner’s optical system (see my earlier reviews for details about the MTF calculation method).
The graph above shows you the MTF for the test patterns. I took the leftmost, 30lppi pattern of an Applied Image QA-69-P-RM target as the reference area. The MTFs are calculated for the green channel of the target image. The following MTF diagram is based on the obtained data:
The diagrams suggest that the Perfection 4490 is as good as its device category and delivers the declared optical resolution.
The profiling procedure helps determine the color gamut of the scanner and to see how far the colors deflect from what they should be. So, I create a profile that can be later used for ensuring a natural color representation by specifying the profile in the driver’s settings. Moreover, I have the digital values of the color tones of the IT8 target which can be used to create the following diagram of the gamut of the Epson Perfection 4490 scanner:
The triangle-outlined gamut is a projection on the plane and shows the scanner’s palette in the visible light spectrum. Knowing the coordinates of the vertexes of the triangles, it is possible to calculate their areas for comparison.
The next diagram is constructed by calculating the difference between the colors of the color target and of its scan. Note that Color Difference values above 5.0 are discernable by most people, i.e. evident for the “average” human eye.
As you can see, the Perfection 4490 is noticeably worse than the top model of the series when scanning reflective originals. Color discrepancies occur in the darkest areas of the color target. I should note, however, that the manufacturer uses a special lamp in the Perfection 4990 with an intensified blue constituent of the spectrum. The Perfection 4490 lacks this feature and this explains the results.
And the last part of today’s tests is probably the most important of all. It deals with scanning quality.
To check the scanner’s depth resolution I put a few pens on the scanner’s glass and scanned them. Here’s the result:
Volumetric objects scan
A high depth resolution helps get fine scans of the centerfold of a book which is necessary for correct operation of OCR programs.
Next I scanned a standard 10x15cm photograph in three modes: Auto Exposure, ICM and Auto Exposure with enabled Color Restoration.
Auto Exposure mode
Color Restoration enabled
As you can see, the best result is achieved when you use the native ICM profile. Color Restoration technology intensified the B channel and result in a distortion of the original colors.
The Perfection 4490 doesn’t allow the user to choose any dust removal technology when a reflective original is digitized; Digital ICE and Dust Removal remain inactive in the driver window in this case.
I liked how Digital ICE for Prints worked in the top-model Perfection 4990 and I don’t quite understand why it is missing in the Perfection 4490. I think this makes the scanner less appealing for the customer. If you compare Epson’s scanners with Canon’s CanoScan series, which are their main competitors in my opinion, Epson wouldn’t win the comparison. Even the junior model of the CanoScan series features a dust removal technology (the Reduce Dust and Scratches option) which works on photographs like a regular vacuum cleaner as I could see in my earlier tests. And even the junior CanoScan model supports hardware FARE Level 2 technology. Epson doesn’t offer such technologies in its entry-level and mainstream solutions, unfortunately.
Now let’s see how the scanner scans transparent originals. Besides a test target IT8, I took a medium-format slide and an old 35mm film.
Medium format film scan
Actual size scan fragment (optical resolution)
with Digital ICE for Films enabled
I have no serious complaints about the quality of scanning medium-format film. The scanner does its job well enough here. But the small window in the holder for this form-factor doesn’t permit you to scan two frames at a time – only one frame and a half fit in.
The 35mm film was the next original to be scanned. I digitized it in Auto Exposure mode and also with enabled Digital ICE for Films. Here’s the result:
No Digital ICE for Films
Digital ICE for Films enabled
This scan of a black-and-white negative film with enabled Digital ICE for Films is given only to illustrate the fact that this technology doesn’t support films of that type (and Kodachrome 64 Professional films, too) as the developer honestly warns you. As you can see, the digitized image has such distortions that cannot be removed by any amount of post-processing.
Finally, I want to show you some scans of test targets. They will help you form your opinion about the scanning quality of the tested scanner:
A scan of Kodak Q-60R2 reflective target in Auto Exposure mode
A scan of Kodak Q-60R2 reflective target
with ICM Color Management enabled
A scan of Kodak Q-60R2 reflective target with no Color Correction
A scan of Kodak Q-60E3 transparent target in Auto Exposure mode
A scan of Kodak Q-60E3 transparent target
with ICM Color Management enabled
A scan of Kodak Q-60E3 transparent target
with ICM Color Management and Digital ICE for Films enabled
A scan of Kodak Q-60E3 transparent target with no Color Correction
This review is approaching its end, so it’s time to sum it up in a few words. And in my opinion, the Epson Perfection 4490 Photo is a somewhat insipid, aimless product. It has a rather high price ($250) but lacks some useful functions. I don’t like that the scanner’s bed is not firmly fixed within the case. As a result, the lid lock shifts the bed when you close the lid down. The holders for transparent materials might have been better as I mentioned earlier. Digital ICE for Films doesn’t work correctly with some types of film, and there is no technology to remove dust and scratches from reflective originals.
I don’t think this scanner is going to be popular because there are better and cheaper models on the market. As a result, the Perfection 4490 is a scanner that for the first time put the perfection of the series in doubt.