Newsgroups: comp.human-factors
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From: delise@mikado.dfe.dec.com (Chris DeLise)
Subject: Re: Track ball on a keyboard?
Message-ID: <1991Jun12.223302.13529@oct17.dfe.dec.com>
Sender: news@oct17.dfe.dec.com (Usenet News Account)
Reply-To: delise@mikado.dfe.dec.com (Chris DeLise)
Organization: Digital Equipment Corporation - Santa Clara, CA
References: <1991Jun12.142307.210@ux1.cso.uiuc.edu> <91163.083144CJS@psuvm.psu.edu>
Date: Wed, 12 Jun 1991 22:33:02 GMT

I've had a chance to use the portable Mac trackball - It is placed
in a convenient location on the keyboard, and it does work well,
but I believe the problem is that the ball is physically too small
and it is therefore a greater effort to accurately position the
cursor. The large trackballs I've seen attached to a Mac allow the
palm of the hand to rest atop the ball, whereas this one tends to
be controlled by a couple of fingers. It requires an unusual form
of dexterity, much like that needed for finger painting. Although
there it requires no less wrist/arm movement than a mouse, I much
prefer the larger, standalone trackball to the small keyboard one.

Does it belong here, or is there somewhere a newsgroup which already
discusses the physiological effects of mice vs. trackballs, including
posture and neurological complication such as CTS?