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A simple way to copy slides onto your computer’s hard drive A Quick’n’Easy Digital Slide “Scanner” Design by BRIAN COULSON Do you have a large collection of slides which are deteriorating by the day? Are they growing mouldy or becoming discoloured? Then there is no time to waste. Get them onto your computer’s hard drive before it is too late. This method is very quick, simple and does not require any electronics. W e’re sure a lot of readers would be familiar with this problem, because many people have large collections of slides (transparencies) which they have collected over the years, or boxes inherited as older generations pass on. They’re often of too much sentimental value to throw out, so they sit in the back of a cupboard somewhere, perhaps not seeing the light of day for perhaps decades. But if you have looked at any of them recently, you may well be horrified at their deterioration. Slides suffer from two main problems – they discolour or they grow mouldy. So how do you preserve your priceless family history? If you don’t do something soon, it may well be too late to recover any image at all. Once an image starts to deteriorate, it keeps on deteriorating. And some slide films of yesterday are well known for deteriorating virtually from day 1! Perhaps you even have a scanner – but have been putting it off for a rainy day when you will get down to it. But most flat-bed scanners are not suitable for scanning slides because their light source is reflective, not transmissive. Even flat-bed scanners with transparency adaptors are seldom ideal, being a compromise. To scan a transparency properly, you need a scanner designed for the 84  Silicon Chip purpose. And they don’t come all that cheap (unless you can pick one up on eBay – and if you want one, there are quite a few to choose from!). But there is a method available to anyone with a reasonable digital camera (say 5-megapixel or better with a macro lens). With that, you already have most of the solution. With the simple set-up described here, you can rapidly scan a lot of slides – much more quickly than if you used a specialised scanner. It’s cheap, not-so-nasty – and it works reasonably well! We must point out that the method described here can never achieve as good a result as you would get from a dedicated slide scanner. In fact, we did an A:B comparison with our Canon slide scanner and found that while the method works, and is fast, the comparison of quality of A light source (40W bulb mounted in a tin can!), a slide holder with an ice-cream carton lid “neutral-density” filter and a digital camera with macro lens – that’s all there is to this you-beaut digital slide scanner! siliconchip.com.au Here’s the result we achieved using the set-up described here. It’s not too bad, considering the simplicity – but you would not be able to enlarge it much beyond postcard size. The other BIG advantage is that this took about 10 seconds to set up and capture. resultant picture is chalk and cheese, especially if you want to enlarge the image beyond postcard size. We’ve reproduced a couple of images from our experiments to show the difference. We used both a 5MP Fuji “happy snap” (albeit with macro function) and a 6MP Nikon DSLR fitted with a quality macro lens. There wasn’t much difference. We found that we could print both to postcard size; any larger and the quick method resulted in quite markedly inferior results. Having said that we know that, by far, the lion’s share of prints made from digital images are no bigger than postcard size, so this limitation may not even be of concern. It’s certainly good enough for the pics to share amongst family members. If you have a digital camera, give it a go: you have nothing to lose except a bit of time! The set-up The complete set-up consists of a digital camera, a slide holder which doubles as a glare shield and a light source. The camera shown in these photos is a Ricoh 3MP with macro. Its minimum focus distance (macro) is 12mm. It was used in the macro mode; the distance from the lens (extended) to the slide was about 25mm. But as already noted, we think you should use a 5-megapixel camera as a minimum (and these are becoming remarkably cheap these days). The method is very simple. A slide is placed in the holder which is backlit siliconchip.com.au For comparison, this is from our dedicated Canon 4000AS Slide Scanner. Overall, the definition is quite a lot better – but this took about ten minutes to set up, scan and save! Limitations of the offset printing process may not show the resolution but this could be enlarged to A3+ without problems. by a standard 230/240VAC 40W incandescent globe. A neutral density filter placed behind the slide stops it getting too hot, while at the same time ensures that the light is evenly distributed. The camera is focussed onto the slide, you press the button and you are done. You only have to focus the camera once, as it remains in position for each shot. Once you get into the swing of things, removing and replacing slides and pressing the shutter button, you can scan slides at the rate of one every few seconds. You can certainly get through a batch of a few hundred in under an hour. Take it from us; this is very much faster than you could do it with a specialised slide scanner. After you have done a batch, you can download the shots into your computer for further processing with Photoshop or similar photo-processing software. You could then print them on your own colour inkjet or laser, or simply take a CD or flash memory stick to the local digital processor to get them printed. The slide holder is very basic and we are sure that readers will be able to come up with more refined versions, if they wish. As you can see from the photo, it consists of a piece of timber with a block at one end to place it on a slope. The slide holder was made from two pieces of 3-ply with appropriate cutouts, glued together. Note that the holder is open on the camera side which makes for faster loading of the slide. Having the unit on a slope helps hold the slide in position, as well as making it easier to view the camera’s rear fixed screen. Although the featured camera only has auto focus in the macro mode, this did not prove a problem, as it focuses in about one second. The overall dimensions of the slide holder may seem larger than necessary but it also functions as a light shield when you are working at the camera end. The light source is a standard clear 40W Crompton Fancy Round incandescent lamp mounted in a standard cordgrip lamp holder and fitted inside an 825ml fruit tin. The clear lamp was found to give better lighting than a 40W frosted lamp. The fruit tin protects the light from physical damage and prevents contact with the very hot globe. The tin itself gets quite hot but not nearly as hot as the naked globe and it prevents local glare and light flare. The neutral density diffuser on the slide holder is a piece of white plastic cut from an ice-cream container. So there you are: a crude and simple jig for scanning all those slides. It does not need to be anything fancy although we would be inclined to make a better mounting arrangement for the camera so that if it is set up for fixed focus, it will not move around while you shoot each slide. Our thanks to Brian Coulson for coming up with this very simple set-up. SC June 2008  85