How to differentiate between click (and release) button and press (and hold) button
I'm working on an interface for an industrial application. It's a portable touch screen that controls an industrial machine.
Like any interface we have buttons which triggers various behaviour when you click on them. Now we want to implement another type of button which does something as long as the button is pressed.
I've been trying to find any convention regarding how to differentiate these two types of buttons. In the real world the "press and hold" buttons are (as far as I know) usually round. Like in this example with a control box for a tailgate lift:
But then again, most buttons in the real world are round...
What we've done before is adding something on a label above the button saying "Press and hold to..." but now we want to have a specific button.
- Does anybody know of any conventions regarding this?
- Does anybody have suggestions on how we can differentiate between a click (and release) button and a press (and hold) button?
Thanks!