Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!mahendo!wlbr!lonex.radc.af.mil!andrewsh
From: andrewsh@lonex.radc.af.mil (Harold G. Andrews II)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: Gray Scale Graphics For HP IIP
Message-ID: <1991Mar12.163034.18538@lonex.radc.af.mil>
Date: 12 Mar 91 16:30:34 GMT
References: <7784@drutx.ATT.COM> <3370015@hpsgwp.sgp.hp.com>
Organization: Rome Laboratory, Griffiss AFB, NY USA
Lines: 52

In article <3370015@hpsgwp.sgp.hp.com> plim@hpsgwp.sgp.hp.com (Peter Lim) writes:
>
>> In article <7784@drutx.ATT.COM> bal@drutx.ATT.COM (LesebergB) writes:
>> >[... Looking for grayscale on an HP IIP...]
>>
>>[...My response.  Not possile...]
>>
>NOT TRUE MAN. It should be rephrased as "All HP and compatible (which is
>almost all laserjets) laserjets before the series III.". The series III
>has Resolution Enhancement Technology which essentially controls the
>size of individual dot deposited on the paper. This is what essentially
>gray scale is about.
>
>Actually some third party products connected to the LaserJet II's video
>port allows you to do something similar. Can't remember the name of
>any of these products though. These products work only with the Series II,
>not anything else (forget about the IIP, IID etc.).
>
     I just responded to another individual on the comp.graphics news group with
other objections.  The series III's Resolution Enhancement Technology has
the ability to change to dot pitch, primarily to allow variable dot pitches
to help reduce jaggies.  This does not address the problem of grayscale.
Grayscale images involve varying the amount of toner deposited onto the paper.
Laser printers cannot, at this time, do that.  What they can do, through
the use of dithering and halftones is give the appearance of grayscale. 
When you boil it down, though, laser printers are incapable of producing
true grayscale images.

     The other products you are thinking about, I believe are add on boards
for both an ISA bus, of in some instances for the laser printers themselves,
which improves the regular 300dpi resolution to somewhere close to 1000dpi.
Using these products, you can tightly pack the dots, so it is easier to produce 
the illusion of grayscale.


      Have a good day...
>>
>Same to you  :-).
>
>
>Regards, Peter Lim.


-Andy

*******************************************************************************
* Harold G. "Andy" Andrews II, 1Lt, USAF  *  "Many the man whose punctuality  *
* andrewsh@lonex.radc.af.mil              *   serves only to warm his chair." *
* Rome Laboratory/IRRE                    *                                   *
* Griffiss AFB, NY 13441-5700             *   - M. Kabrisky                   *
* (315) 330-7788  (AVN Prfx 587)          * (Not an official  USAF viewpoint) *
*******************************************************************************