Slide scanner reviews

• Mounts and carriages - all in this test were plastic, but functional. The slides lie on the flat-bed scanners' glass plate, which could lead to fingerprints and dirt on the glass. The Microtek 4000tf uses small plastic springs to clamp the slides, which could be a bit fiddly and the slide carriage extends out both ends of the scanner needing 60 cm in total to avoid obstructing it. The Nikon V ED can only scan one slide at a time.
• Knobs and dials - it's handy to be able to start a scan by pushing a button on the scanner itself. All but the Canon FS 4000 US, Nikon V ED and Microtek 4000tf had one. The Konica Minolta Elite 5400 also has a manual focus control knob.
• Software - being able to find what you need easily and go from one function to another with as little effort as possible are important functions for software. All in this test scored OK or better, but the Nikon V ED and Microtek 4000tf software was more difficult to use than the others.
• Dust - is a real problem when scanning. You can clean your slides, but dust in the scanner can be harder to remove. All the slide scanners except the Nikon V ED and Artixscan 4000tf have a gate to help keep out dust. The former has only a narrow opening and the latter comes with a dust cover and cleaning kit.
• Connections - all have a USB connection and the Canon 9900F, Epson 4870 Photo, Konica Minolta Elite 5400 and Microtek 4000tf also come with FireWire, which could reduce the time to scan if you're using high resolutions. USB 2.0 is faster than USB1.1, but its transfer speed can be affected by the amount of processing the computer is doing.
• Focus - all products have auto-focus, but this isn't always effective. Manual focus is available via a software control for all products except the Perfection 4870 Photo and Artixscan 4000tf. The Konica Minolta Elite 5400 has a manual focus knob.
  

We expected the flat-beds to have problems with sharpness because there's a piece of glass between the scanners' lens and the slide. Although we found this is the case, both flat-bed scanners use sharpening tools by default to reduce this problem to a negligible level for some users. Time, the Achilles heel of all slide scanners, is the factor that really sorts the products out (see Slow, slower, slowest).

What to buy

Brand Price

• Konica Minolta Dimage Scan Dual IV - $699
  
• Nikon Coolscan V ED (LS-50 ED) - $1295

The Konica Minolta Dual IV is relatively inexpensive, quick and easy to use. It has no cleaning function and its image quality is only OK in comparison with the others, but it's a good choice if price is your major consideration.

Although it's not as easy to use, the Nikon V ED's performance is very good and it comes with a cleaning system - Digital Ice. If you need to scan large batches of slides at once, rather than one at a time, you'll need to purchase the 50-slide attachment for an extra $879.

Flat-bed scanners have the advantage of being able to scan reflective material as well, while a dedicated slide scanner can only cope with negatives and slides. But the buying decision also has as much to do with quality as it has with print size.

Until recently, flat-beds weren't able to provide the same resolution as a slide scanner. That's no longer the case, so printing up to A3 from a slide is quite realistic without having to resort to interpolated resolution (see Dictionary below), which can degrade the image. Size is only one factor; sharpness, quality of the colour reproduction and the ability to deal with lots of shades of grey (from almost pure white to almost black) are also important.

When their sharpening function was turned off, the images produced by the flat-bed Canon 9900F and Epson Perfection 4870 Photo weren't as sharp as their slide scanner counterparts. However, they produce acceptable images if their default sharpening functions are left on. If you need to further sharpen the image, this initial manipulation may cause problems. It's generally better to rely on a sharp lens rather than a software solution. The Canon FS 4000 US and Nikon V ED slide scanners impressed our panel with their sharpness.

You'll probably have to do some colour correction at the preview stage or after scanning regardless of the product you choose. The Epson 4870 Photo was a good performer in this area while the Canon 9900F scored OK. The slide scanners were generally good, but both the Konica Minolta scanners only managed OK scores. The Microtek Artixscan 4000tf and Nikon V ED were the most consistent performers in this area.

If you've limited space, the flat-beds are probably not for you. They're quite bulky (see Results Tables for sizes) and need space above for their substantial lids. The lid on the Epson 4870 Photo felt unstable when upright and had to be held it in place when positioning slides, which could be annoying.

How we tested

We scanned several slides, a black and white negative, and a colour negative at the scanners' default and best optical settings with the cleaning function (if available) on and off. The resulting files were printed using a Canon i950 printer on high quality photo inkjet paper using the software supplied with the scanner. We appraised the install and uninstall procedure the clarity and comprehensiveness of the paper and on-screen the help files and the scanning software. We also assessed the ease of use of the scanners for features such as slide carriers or mounts, buttons and controls.

We measured the time it took to scan a slide and the resulting prints were appraised by a panel of three experts for sharpness, colour and exposure.

We used the same Pentium 4 3.0GHz computer running Windows XP Home for each scanner. The quality of the two flat-beds was also appraised for reflective material (see Dictionary below). Our testers rated them superior to the top products in our last flat-bed scanner test).

Dictionary

• Bit depth: A measure of the number of colours that a scanner can recognise and capture. 42 bit = 14 levels of intensity per colour (Red, Green and Blue) 48 bit = 16 levels of intensity per colour.
  
• Interpolation: is a software trick that increases or replaces detail in an image by adding pixels between those measured by the optical resolution. When used to increase resolution this can create very big files.
  
• Reflective material: normal paper photographs, magazine pages etc. reflect light, whereas light passes through transparencies (slides).

Konica Minolta Dimage Scan Dual IV

Price: $ 699

Good points

• Useful scan button brings up driver software
• Vents along side of unit make easier to carry

Bad points

• Plastic slide and negative holder
• No firmware cleaning tools
  

Konica Minolta Dimage Scan Elite 5400

Price: $ 1549

Good points 

• Useful scan button brings up driver software
• Good manual focus

Bad points

• Plastic slide and negative holder
  

Nikon Coolscan V ED (LS-50 ED)

Price: $ 1295

Good points

• Quick to scan
• Sturdy slide and negative holders
• Good flash tutorials

Bad points

• Can only scan one slide at a time
• Onscreen windows can't be minimised
• Installation in several parts
• Inaccurate crop tool
  

Canon CanoScan 9900F

Price: $ 699

Good points

• Useful scan button brings up driver software
• Secure lid
• Software pleasant to use

Bad points

• Software extras take a while to install
• Slides placed on glass plate could lead to dirty glass
  

Microtek ArtixScan 4000tf

Price: $ 1759

Good points 

• Comes with FireWire card, calibration slide, dust cover and cleaning kit

Bad points 

• Too many floating onscreen windows
• Plastic slide and negative holder comes out back of unit as well as front
• Complicated colour management software setup
• No firmware cleaning tools
  

Epson Perfection 4870 Photo

Price: $ 899

Good points

• Useful scan button brings up driver software '
• Software pleasant to use, but you need to scroll to find the cleaning tools

Bad points

• Lid was unstable in the upright position
• Extra software slow to install
• Slides placed on glass plate could lead to dirty glass
• Slow to scan
  

Canon CanoScan FS 4000 US

Price: $ 1299

Good points

• Driver install was quick but extra software slow to install

Bad points

• Plastic slide and negative holder

The time it takes to scan a slide is largely dependant on the quality settings you choose. The lower the quality, the faster the scan. However, scanning times differ significantly when set at the top optical resolution and maximum bit depth. If you've lots of slides that need cleaning, you could be looking at weeks, rather than hours, of work.

The Konica Minolta Dual IV was the fastest. It shares equal lowest resolution (3200 dpi) with the Canon CanoScan 9900F, but took about 32 seconds to scan a slide as against 171 seconds for the Canon 9900F. The slowest was the Canon Canoscan FS 4000 US at about 393 seconds. The Nikon V ED was also quite fast at about 49 seconds - the others took between 102 and 178 seconds.

However, these timeframes greatly increase if you turn on the slide cleaning systems (see Cleaning up below). We didn't score the timeframes using the cleaners because we thought it was unlikely you would use them all the time, even though they are a useful tool. The Nikon V ED scanned slides fastest with the cleaning tools on (about 105 seconds), while the slowest was the Konica Minolta Dimage Scan Elite 5400 at about 541 seconds. The others took between 360 and 455 seconds.

Cleaning up

Digital Ice and FARE is technology designed to remove the effects of dust and scratches from slides or negatives. The former is a Kodak product and is available on several brands of scanner (Epson, Konica Minolta and Nikon in this test), The latter is a Canon technology.

Both work in a similar way, using a combination of hardware and software. Scanners measure the level of red, green and blue in an image, dot by dot. These are called the red, green and blue channels. A scanner with FARE or Digital Ice introduces an extra infrared or (D) channel. Most slides and colour negatives are transparent to infrared light, so if the slide is clean this extra channel will be clear. Dust, mould and scratches are not transparent and appear in the channel as dark areas. The software uses this channel in combination with information from the areas close to the fault to fix the image.

We used a slide that had been very badly affected by mould, as well as some with small amounts of dust and minor scratches. The results across all brands are impressive. There was some evidence of interpolation (see Dictionary) around the worst affected areas, but these could be fixed. Two spots on our mouldy slide were too degraded to be cleaned by either system, but fixing them manually would only take a few minutes - whereas fixing the original slide manually would be nearly impossible.

Traditional silver-halide black and white film and some specialty slide films cannot be used with this technology. An additional drawback is time, but it could be the difference between a lost image and one recovered forever.