The housing and ball have been given the black treatment but are otherwise the same as their white cousins for PCs and Suns. The two-inch trackball with its pair of buttons on either side handles smoothly, while the sturdy housing withstands the everyday desktop war zone. A bundled application, Max.app, allows fine-tuning of the trackball movement, though for coarser settings the standard NeXT Preferences panel still works.
Switches on the bottom of the device allow you to exchange right- and left-button functions, turn off the click-lock feature, double or halve the cursor speed as set by Preferences, and reverse the vertical and horizontal directions.
The RollerMouse handles normally with standard settings but becomes unwieldy when the cursor speed is doubled. Max.app heightens sensitivity at the increased speed by allowing the user to set, on a graph, 14 points of acceleration; the only way to find the settings you like is to experiment. It took me several days to find a response curve with which I felt comfortable, but the increased responsiveness made me loath to return to my mouse.
The click-lock feature is useful though somewhat nonintuitive. By pressing a lock button, you can remove your finger while still having hold of your window, icon, or highlighted element. You can press any button to release. Once you've added click-lock to your button vocabulary, you can answer the telephone without accidentally dropping a file into the wrong folder.
Comfort and ergonomics is a critical issue with any input device. Unfortunately, using the RollerMouse became uncomfortable for me after a few days. Other NeXT-WORLD staffers tried out the trackball and reported mild wrist and arm soreness. We don't know how to account for this, since RollerMouse versions for other platforms have received excellent reviews with few complaints.
Our experience probably stems from having to mouse around in the NeXT user interface far more than we would have to on other platforms. Oddly, I found that turning the trackball around, cord to the front, was a more comfortable position for me. Reversing the horizontal and vertical directions permitted this adjustment while maintaining normal cursor movement.
Comfort is a subjective issue, so users should try the RollerMouse for themselves before reaching a conclusion about its ergonomics. A NeXT-compatible trackball fills an important void in the NeXT product universe. With the ADB compatibility provided in newer NeXT systems (see "Ergo Style" in this issue), however, there will be many available input-device options. For those unwilling or unable to convert to the new systems, RollerMouse from CH Products provides an alternative worth considering.
by Kristin Dyer
A solid trackball with superior sensitivity and speed. Users should test for ergonomic comfort before they buy.
CH Products, 970 Park Ctr. Dr., Vista, CA 92083.