The best way to rasterise a Postscript file is to pass it through Photoshop. Photoshop's rendering algorithms are pretty much the best and it'll do a nice job of anti-aliasing the file as well.Unfortunately Photoshop isn't the universal file-reader we'd like it to be. Photoshop is supposed to be able to rasterise a reasonable range of Postscript files, but in practise seems only to be able to turn Illustrator files - and even then pretty simple ones - into a bitmapped graphic.
If you've got Illustrator, fine. The only things you may need to do to rasterise successfully are turn the image into an older file format, such as Illustrator 3.0, and to keep going back and editing out unnecessary details if Photoshop consistently falls over or gives you the dreaded "nesting too deep" alert (that basically translates as "this is way too complicated for me."
If, on the other hand, you're like me and you prefer Freehand then you have a slightly more roundabout route to bitmap heaven.
Freehand 5.5 comes with all sorts of screen-design goodies. It accepts GIFs as part of a layout for starters, and it can generate imagemaps (which is a topic we ought to cover at some point, although it's a little off our stated course). But best of all it can take an onscreen selection and turn it into an anti-aliased PICT file, ready for conversion to a GIF.
Unfortunately, this is memory intensive and sometimes simply fails.
This leaves you in an all too familiar situation. You can export the file as a supposedly interchangeable EPS, but Photoshop refuses to rasterise them, leaving you with a dubious preview. The same goes for any EPS from Quark XPress.
What to do then? Thankfully you have a few tricks left. One is to go out and buy a copy of Adobe ScreenReady, which gets around thiese problems wholesale. It doesn't cost an awful lot - it's just over a hundred pounds. If you're converting truckloads of EPSs it's well worth a look.
If you're less well-off there are a couple of shareware routes that you can take.
There's a particularly useful piece of shareware called EPSConverter that will prepare other EPSs for rasterising in Photoshop. It takes a standard EPS from Quark or Freehand and turns it into an Illustrator .art file, which Photoshop should happily rasterise.
If you don't have, or don't want to use, Photoshop, then there's a two-stage route you can follow. EPStoPICT is an earlier piece of shareware from Sam Weiss, the same guy who wrote EPSConverter.
EPStoPICT, as the quicker among you have probably figured out, takes an EPS file and rasterises it into a PICT. It's all fairly straightforward: just pick a file and let it go.
However to get the best out of it you'll need to tinker with the preferences. Go for a high resolution raster like 300dpi. That may seem daft considering that what you want is a 72dpi image but EPStoPICT creates only un-anti-aliased images and isn't very good at rasterising at only 72dpi. 300dpi gives you room for error and, as it happens, prepares the image perfectly for the next process.
Antialias
is an even more plainly stated application that takes an image and produces
a really nicely antialiased images from it. The only trouble is, the way
it does it is by reducing the image in size and then working out the bits
that need the intermediate tones from that. Of course, if you're starting
with a suitably huge image this isn't a problem.