laser-lovers@uw-beaver (06/05/85)
From: Mark Wadsworth <mw@uci-icse> I have seen it stated somewhere that the Imagen 10-240 has square pixels, while the 8-300 (Canon LBP-CX) has round ones. Is this a real difference? Could I look at the output and tell? Which shape is to be preferred, other things (like resolution) being equal?
laser-lovers@uw-beaver (06/05/85)
From: Nick <NNicoll.ES@Xerox.arpa> I would like to join and enlarge a discussion of the shape of pixels to include the size of pixels. As most of you might know, a scanning laser places an oval shaped pixel with the height/width ratio dependant on the distance the pixel lies from the centerline of the paper in the feed direction. I believe the ratio varies by ~15 to 20%. Fonts designed for such printers should take that variation into account but the ones I've seen don't. There is a noticable variation between characters at the edge, and characters in the middle of a page printed on a scanning laser printer. This variation also changes the size of the pixel, but not as much as the different printers of either scanning or cartridge types do. I believe the Imagen 10-240 has a significantly smaller pixel size than the Canon LBP-CX but I have not had a sample of both under my microscope, I'm just going from eyeball measurements. If anyone does have the results of actual measurements I'd be glad to hear from them. \\ Nick
laser-lovers@uw-beaver (06/05/85)
From: imagen!geof@Berkeley I think you've got it reversed. The 10/240 uses the Canon LBP-10 engine. I am told that its pixels are roundish, although I'm not sure. The 8/300 uses the now famous Canon LBP-CX engine. Its pixels are rather square. The shape of the pixels is very noticeable. For example, the jaggies on rounded letters or angled lines are much easier to see on the LBP-CX than on some other machines, so font tuners must be much more careful, and line drawings tend to look more jaggy. On the other hand, filled regions and horizontal or vertical lines look much more solid. Textures involving single pixels surrounded by white space are also darker on the CX. Fonts for the 8/300 look different when printed on other engines. Usually, they look too slender, and the serifs vanish. Conversely, fonts prepared for other engines look stodgy on the 8/300, since even a single pixel serif is very visible. It takes a good deal of effort, for example, to get compatible fonts for the CX and other engines because of this problem. That's one reason why downloaded fonts are starting to be a worse idea (and why Imagen has started to sell printer resident fonts). While I'm on fonts.... To answer a previous comment on the list, I would agree (without consulting our marketing department -- I'm writing as a civilian) that anyone buying an Imagen printer for use with DI/TROFF should seriously consider buying printer resident fonts with it (and paying the extra price for them) for the above reasons, as well as to avoid the need to use the much deprecated versions of the Computer Modern fonts that we distribute for free (I guess that you get what you pay for). I would especially recommend this to users who intend now or in the future to have different IMAGEN printers in house (8/300 + 12/300 or 24/300). On the other hand, not all of our customers use the printer as a text output device (some use them mostly for graphics). Also, some customers have their own fonts, and don't want to pay for ours. It is thus reasonable for Imagen to sell the fonts separately from the printers. - Geof Cooper Usual Disclaimer: I am an employee of Imagen. The above views are mine, and not necessarily those of Imagen Corporation.