deskthority

I'm playing with a Logitech Cordless Trackman Fx (http://support.logitech.com/en_za/produ ... rackman-fx#).
There is one pretty big problem with this trackball - there is pretty bad acceleration (high resolution vs speed error to be precise). What I mean by acceleration is this: When I move the ball slowly the cursor travels distance x. When I move the ball faster, but cover the same distance, the ball travels distance x/2 for the same movement of the ball. And when I spin the ball the cursor stays stationary or even oscillates at the beginning and then stars moving.

My question is - Is this normal/expected for this old trackball (the device is in pretty good condition, it looks almost unused)? Does this same problem happen with modern hi-dpi trackballs? Is this problem connected with the price range of the trackball? Any experience you can share will be welcome.

If you're using Windows it's likely the operating system's mouse acceleration, not the hardware itself.

Google "markc mouse fix" if you want to fully disable acceleration.

I'm on linux and my normal logitech m500 mouse is working just fine.
Also isn't acceleration expected to cause larger distance when moving the device faster?

When I move the ball faster, but cover the same distance, the ball travels distance x/2 for the same movement of the ball.

By x/2 do you mean 1/2 the distance when moving faster? That's more commonly known as deceleration, though it still is acceleration if we're talking physics.

And when I spin the ball the cursor stays stationary or even oscillates at the beginning and then stars moving.

Sounds like you're spinning it so fast that the sensor loses tracking data.

ohaimark wrote: ↑By x/2 do you mean 1/2 the distance when moving faster? That's more commonly known as deceleration, though it still is acceleration if we're talking physics.

Yes, if I move the ball faster the cursor travels half the distance on screen compared when I move the ball slow.

ohaimark wrote: ↑Sounds like you're spinning it so fast that the sensor loses tracking data.

Yes, I think this is what happens. The question is does this same thing happen with modern sensors used by current trackballs on the market and especially with the Pixart ADNS-9800 in a custom built trackball?

It probably doesn't happen with modern sensors. They've improved immensely in terms of tracking capabilities; some modern mice can track well on glass, for example. Older optical/laser mice tend to struggle under those circumstances.