CXT105@psuvm.psu.edu (Christopher Tate) (04/17/91)
Is there any difference between, say, a 106 dpi gray screen and a 100 dpi
screen? Or a 53 dpi screen and a 55 dpi one?
Don Lancaster spoke in his column in Byte magazine last summer about the
"secret" gray map of printers, and (to me, at least) implied that there
were only so many distinct combinations of resolution and angle that the
printer can produce. Apparently there's some way of investigating that
"secret" gray map, since Lancaster provided a diagram intended to represent
it for a LaserWriter II.
Hmmm... it would seem this is a device-dependant question. I'd certainly
expect different gray maps from a 300 dpi and a 1250 dpi printer!
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Christopher Tate |
Student-Type Person | Migratory lifeform with a
cxt105@psuvm.psu.edu | tropism for bookstores.
{...}!psuvax1!psuvm.bitnet!cxt105 |
cxt105@psuvm.bitnet |andrew@visix.com (Andrew Bernard) (04/18/91)
In article <91106.223452CXT105@psuvm.psu.edu> CXT105@psuvm.psu.edu (Christopher Tate) writes: >Is there any difference between, say, a 106 dpi gray screen and a 100 dpi >screen? Or a 53 dpi screen and a 55 dpi one? > This depends on the device. There's only so many ways a given halftone pixel can be tiled over a bitmap to give a pleasing result. The larger the spot is, the more it can be shifted around to produce different angles. The spot size is inversely proportional to the halftone frequency. This is a considerable simplification of what goes on inside the RIP. >Don Lancaster spoke in his column in Byte magazine last summer about the >"secret" gray map of printers, and (to me, at least) implied that there >were only so many distinct combinations of resolution and angle that the >printer can produce. Apparently there's some way of investigating that >"secret" gray map, since Lancaster provided a diagram intended to represent >it for a LaserWriter II. > There is a program which will reproduce the possible spot shapes for a PostScript printer, given a certain frequency. It's available in one of the more advances PostScript books, but the title eludes me. Can anyone help me out here? It's the one with the A-Z letter poster. -- andrew bernard ring the doorbell on your mind software engineer but it's locked from the outside visix software -dinosaur jr. andrew@visix.com
amanda@visix.com (Amanda Walker) (04/18/91)
In article <1991Apr17.194643.24548@visix.com> andrew@visix.com (Andrew Bernard) writes: There is a program which will reproduce the possible spot shapes for a PostScript printer, given a certain frequency. It's available in one of the more advances PostScript books, but the title eludes me. Can anyone help me out here? It's the one with the A-Z letter poster. Real World PostScript, by Roth et al. -- Amanda Walker amanda@visix.com Visix Software Inc. ...!uunet!visix!amanda -- Calm down--it's only ones and zeros.