[comp.text] Please Post Responses

ries@venice.SEDD.TRW.COM (Marc Ries) (07/19/90)

Please Post Responses (Was: Re: Inquiry about closeout scanners

Also, I read recently (Publish?) where the maximum grey-scale gradient/shade
that a typical 300dpi laserjetII is about 15 (i.e., the printer only output from
white to black via ~15 different grey-scales).  The point being that if you
can only print 15 different grey-scales, what good is a 256 grey-scale scanner.
Similar args might be made for a scanner supporting more that 300dpi if
your printer is limited to 300dpi.  

Anyway, Is this hogwash or ?   

Thanks,

Marc Ries

chute@bru.MAYO.EDU (Chris Chute) (07/23/90)

I had one reponse, here it is:

::You've been reading Computer Shopper -- Camco, Envisions, and/or another
::ad I can't remember.  The $399 prices have been there for almost a year.
::Only problem: those scanners are sheet-feed, not flatbed.
::Unless you need one this calendar year, wait for.....
::
::...The $2500 Scrax Machine...!   (my term) ---
::
::a LaserJet-sized combination printer/scanner/fax/copier all in one.
::The idea has been in the news, with several companies said to be in
::the hunt for "every businessperson's desktop".
::
::
::-- 
::Kenneth W. Regan           			Assistant Professor
::Computer Science Dept.				(Opinions not < SUNYaB)
::SUNY at Buffalo, 226 Bell Hall			Tel.: (716) 636-3189, -3180
::Buffalo,  NY  14260				regan@cs.buffalo.edu
::
Cheers,
Christopher G. Chute, MD                   Voice:    (507)284-5506
Section of Medical Information Resources   FAX:      (507)284-1516
Mayo Clinic/Foundation                     UUCP:     chute@medinf.UUCP 
Rochester, MN 55905                        Internet: chute@mayo.EDU

ath@prosys.se (Anders Thulin) (07/27/90)

In article <676@venice.SEDD.TRW.COM> ries writes:
>                                                The point being that if you
>can only print 15 different grey-scales, what good is a 256 grey-scale scanner.
>Similar args might be made for a scanner supporting more that 300dpi if
>your printer is limited to 300dpi.  
>
>Anyway, Is this hogwash or ?   

If you scan only in order to print it out on a 300 dpi printer, it's 
probably true.

If scan in order to examine the result on a monitor it is not. The eye
can distinguish between 30-50 (?) levels of grey.

And if you scan in order to do image processing (enhancement, filtering)
you definitely want as many grayscales as possible.


-- 
Anders Thulin       ath@prosys.se   {uunet,mcsun}!sunic!prosys!ath
Telesoft Europe AB, Teknikringen 2B, S-583 30 Linkoping, Sweden