The artist and photographer's guide to scanning. You've drawn a wonderful piece of artwork, or you've taken a great picture. Now you want to put it on the internet, how do you do it? Everyone knows you need a scanner. But which one, and then what? I've had a *lot* of experience at this, as you can imagine. Here's my Scanning Guide. First you need a scanner. The best one that I've found for negatives, slides and photographs is the HP Smartscan. It really is very smart, and makes good decisions. The scans I get from that are a lot better than scans I get from other scanners. But it's expensive. And slow. If you do use it, be sure to get VueScan, from http://www.hamrick.com It makes a very big difference, VueScan is a *lot* better than HP's software. I mostly use a Nikon 1000. This is somewhat more expensive than the Smartscan, but it uses an additional infra-red sensor to help with removing scratches and dust. Another scanner I'd like to mention is the HP Scanjet 5s. This has a wonderful wonderful feature - a sheet feeder. If you're scanning a lot of things, it means you can load up a batch and leave it going. It'll do photographs, and it'll do ordinary sheets of paper. It comes with an OCR (it reads text and gives you a text file) that is surprisingly good. Also, it's cheap, and doesn't take up the huge amount of space that a flatbed needs. The third scanner is a flatbed. You can get these now for as little as $100. All of them will take full size sheets (European A4 and US legal sized), all of them are colour, all of them are Twain (easy to use). The differences between scanners are mostly in the resolution. I most use an HP C6270 as a flatbed, because it also has a sheet feeder. Some flatbeds claim to also scan slides and/or negatives. The problem is that they're using the same sensors (usually 300 dpi) and that means that they're getting 300 dots on the one inch of negative. And that's a very poor resolution. Even if they half-step, 600 dpi is pretty poor. 300 dpi is fine on an A4 sheet, where you have several inches to scan, but not on a one-inch negative or slide. So, don't use a flatbed to scan negatives or slides. Ignore everything except "Optical resolution" because everything else is advertising puff like "interpolated". I'm assuming you're scanning for the internet. Let's suppose you have a 10 by 8 inch picture to scan. If you scan it at 300 dpi, and then display it on your monitor, it will be 3000 pixels high by 2400 pixels wide. Since most screens are less than half that (800 by 600 or maybe 1024 by 768), they'll only show the left half of the picture ; and they'll only show the top third. Since your monitor is nowhere near that, you won't want to scan it at 300dpi. Let's consider a photograph, 4 by 6. If you scan that at 300 dpi, then you get 1200 by 1800 pixels. Still too big for most screens. You'll be using your graphics editor to scale the thing down. Now you see why you don't need a scanner that is better than 300 by 600 dpi resolution. You won't use it, not for stuff that's going to display on screens. The reason they sell scanners that are better, is that you might print out the thing you scanned. I've seen perfectly good flatbed scanners that are 300 by 600 dpi, costing 39 pounds (about $60). If you want to scan negatives or slides, the flatbed won't do it, unless you have a "transparency adaptor", and even with that, you'll get pretty poor results if the scanner is only 600 dpi. You need 1200 dpi optical at least for those. On the number of colours; jpg uses 24 bit colour. If you get more than 24 bit colour, that's OK, but don't pay for what you won't be using. In other words, a 30-bit, 32-bit or 36-bit colour scanner isn't any better for this purpose than a 24-bit scanner. Next, when you use the scanner, tell it to scan at 150 dpi. If you use the 300 dpi setting, you'll wind up rescaling it down. You might also try scanning at 75 dpi or whatever is the nearest setting it offers to that. One situation when you might use a higher resolution than 150 dpi, is when you tell the scanner to scan only a cropped portion of the picture. So, if you scan only a 2 by 3 inch portion of a 4 by 6 photo, then you'll tell it to use 300 dpi, because then you have a 600 by 900 pixel file. Getting it ready for the web The output from your scanner will be BMP, TIF or JPG. BMP and TIF are exact representations of what the scanner saw. JPG is compressed, using lossy compression. GIF is another format that browsers can understand, but it isn't good for photographs. BMP and TIF are no good for browsers, but can be useful as an intermediate format. Lossy compression means that it uses a clever scheme to discard information that the human eye doesn't tend to notice anyway. Compression can be anything from 0 to 99% (some packages talk in terms of quality, which goes from 100% to 1%, it's the opposite of compression). At 20% compression, you really will find it impossible to tell the compressed JPG picture from the original, except that it will be a fraction of the kilobytes. 30% looks good, too. At 80% compression, you can see the picture, but it's rather blotchy. Good enough for a thumbnail, but no good for a real picture. 70% is also fine for thumbnails. So, if you get to choose the JPG compression, that gives you an idea what to choose. The bottom line is, if it looks OK, then it is OK. Look closely at edges in the picture, they should be sharp, not blotchy. If a scanner doesn't let you choose how much compression, you should try to find out how much it uses. If it uses too much, then you can tell it to output TIF or BMP files, which aren't compressed. Then you can use Paintshop Pro or any other graphics package to convert those files to JPG. Some people only have 640 by 480 pixel screens, most have at least 800 by 600. I'd aim for the output to be 800 by 600 at most. If it looks fuzzy and soft at that many pixels, try rescanning. If you don't have the option of rescanning (or maybe the original wasn't sharp) then use Paintshop or whatever you use, to resample the picture (not resize, resample). If you reduce 800 by 600 to 400 by 300 then you'll find it looks a lot sharper and clearer. Video grabbing Another way to get pictures is to use your camcorder. There's three types; Digital Video, high-band (Hi-8 or S-VHS) and low-band (8mm or VHS). Ordinary domestic VCRs (video recorders) are low-band, and so are the video tapes that you buy. If you're a video enthusiast who makes their own videos, you might have an S-VHS recorder. Television broadcasts are a bit better than high-band. You can get excellent results with something like the Snappy (there's a lot of frame grabbers on the market; I use the Iomega Buz, because it'll grab video as well as stills). Ignore the boast that it can grab 1500 by 1150 or huge numbers like that; the problem is you don't have anything you can feed it that will let it do that. If you're using Digital Video or high-band, you can get 640 by 480. With low-band, you should aim for 320 by 240 (the exact numbers will be a bit different, according to what you use). The best thing to use is PAL Digital Video, you might get as good as 720 by 576 from that (except that most frame grabbers don't let you choose anything besides a few standard sizes). And PAL is a European format, you won't get it in the US. Also, be aware that when you buy PAL tapes, they might be conversions from NTSC (the US standard), and so they won't be up to European quality (or even up to normal US quality). Some high quality VCRs let you pause without noise, and then grab from that. All Digital Video cameras and recorders let you freeze a frame without noise which you can then grab. If your equipment doesn't let you freeze a frame without lots of video noise, you're out of luck, and you'll just have to time your grab carefully. The simplest way to turn a tape from your camcorder into a series of pictures, is to send it to me. I can take one grab per second from the entire tape. Scanning negatives I prefer to scan negatives to prints. Remember, prints are made from negs, so they're second generation. It's better to go to the original and scan that. For me, prints are expensive waste paper. To scan negs, I have the following: Epson Filmscan 200. Cheap ($200 or $300), only 1200 dpi. That means I can scan a neg, and get an image that's something like 1800 by 1200 pixels. If I'm aiming for 900 by 600, that means that I can crop it to half height and width of the original negative. It will also do slides. I don't use the Epson now. It had two big drawbacks. You had to put the negatives into a carrier, which added a lot to the usage time. And it didn't work with Vuescan. HP Smartscan. It costs a bit more, about $400 or $500. It does prints, negs and slides. It does 2400 dpi, but using it is a complete pain, because it doesn't do "batch scanning", it does one at a time scanning. I use Vuescan with it, and that helps, but Vuescan doesn't crop. I have to crop as a separate operation, very fiddly. But it means I can crop to a third or a quarter height and width of the original neg. Nikon 1000. This is around $1000, but it's definitely better than the HP. It has an extra sensor, infra-red. The software uses the information from this to detect and remove surface defects, such as dust and scratches. It scans at 2700 dpi. Further reading http://www.hamrick.com/vsm.html http://www.scantips.com/ http://www.cix.co.uk/~tsphoto/tech/filmscan/menu.htm