It partly depends on what you intend to do with them and what quality of image you want. For any web purposes a drum scanner probably isnt needed.
Transfer old photographs to digital format without losing quality
I first started transferring my slides to digital images in the early 1990s. I used a local shop that provided 640 x 480 images for about $2 each. I then purchased a MicroTek scanner and did hundreds of my own for several years. I used the results in Jigsaw puzzle programs and other games that I published, and also as clipart and royalty free software collections. Since 2006, I’ve also been selling thru various microstock agencies. I’ve used scancafe.com since 2007 – they’re based in India and slide scans start at about $.20. The process is easy
1. You place your order online
2. You ship your images [with UPS tracking]
3. You review your images
4. Your order is shipped [with UPS tracking]
5. You now have digital images on a DVD to enjoy & share
Normally the images are scanned at 7MP, but I get the PRO addons at 300dpi which raises the price to about $.30 . The best feature is that once they scan them, Scancafe sends you an email and you can review the images online. You only pay for the ones you like.
Their support staff has been extremely helpful, and they’ll redo scans if there are problems with lighting, etc. I used mostly 25 ISO Kodachrome and 50 ISO Velvia for my slides. The results, are mostly excellent – there are a few problem type photographs – for sunset, sunrise and other images with a golden light, scanning requires the operator to decide what the ‘true color’ should be. Similarly, images on snow or the high mountains may show up blueish. Scancafe will redo these on request for no additional charge, or you can sometimes get better effects on your own using Photoshop Elements or other software. Grain is sometimes a problem when under high magnification. But for these I use Noise Ninja and the results are accepted by highly selective photostock agencies.