Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site uw-beaver
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!cornell!uw-beaver!laser-lovers
From: laser-lovers@uw-beaver
Newsgroups: fa.laser-lovers
Subject: Re: relative speed of LaserWriter and Dover
Message-ID: <921@uw-beaver>
Date: Fri, 15-Mar-85 13:20:33 EST
Article-I.D.: uw-beave.921
Posted: Fri Mar 15 13:20:33 1985
Date-Received: Tue, 19-Mar-85 05:54:51 EST
Sender: daemon@uw-beaver
Organization: U of Washington Computer Science
Lines: 40

From: starkweather.pa@XEROX.ARPA


Having been the laser scan system and print engine project leader for
the DOVER printer the parameters you mention are somewhat off base. A
DOVER would NOT be $160K! First, it was never tooled the way the LBPCX
Canon engine is. Had it been prepared for production by careful volume
engineering etc. the cost would have been more like $40K for the system
not $160K. Secondly you disregard the number of pages or copies of a
document required. The DOVER system must prepare bands files sure enough
but many people want several copies of manuals, documentation etc. A
DOVER racing a Canon engine with one complex page per job and one copy
of each page is not a typical use scenario. Try comparing typical output
when you want 10 copies of a 30 page document. The DOVER under those
circumstances runs at nearly full speed. 

The LaserWriter is for low volume purposes. The DOVER printers at PARC
generate about 125,000 prints per month per machine. Some machines print
over 250K prints per month. Thats ~40 Canon cartridges a month or more
than one a day. Best print your stuff in the morning before the toner
gets low in the afternoon. The point is that comparing page rates must
be done in light of the print volume required by the average job. The
Canon engine would be shot in no time at 100K prints per month. Also 154
Canon printers would be ~ 200 cubic feet of printers (I do not know how
you would get the prints out of the ones in the center of the cube). A
DOVER is only 50 or so and collectively puts out much less heat. The
"cluster" concept of many small printers does not make much sense in
reality. As far as reliability goes, the DOVER is excellent. On average
I believe that approximately 1 service call or jam clearance per 10,000
sheets is average for our machines. This is dependent on key operator
skill and dependability of course. That may seem like a lot but a await
the data on a Canon printer putting out 100K prints per month. By the
way, how much does the VAX cost in your system?

The DOVER printer system went into service in 1977-1978. When a better
system is available I will be the first to request it. By the way I have
an HP LaserJet and am going to get a LaserWriter but not for several
copies of a 50 page document.

Cheers, Gary Starkweather/ Xerox PARC