how to set the contrast?

I've got a cheap 16x2 LCD from Hong Kong coming, pictured below. I am going to use the shiftLCD library. So, that will take care of the 7 pins driving it. The backlight-I will just hook up with a proper resistor. But what about the contrast. What do I do with that connection?

connect a potentiometer between the negative voltage supply and +5 volts, connect the output to the contrast pin

Great! Sounds easy enough. Something like a 10K?

sounds good.

I use a multi-turn potentiometer. It's a pain to turn this thing if I'm no the wrong end of the scale but once I get there I can adjust my contrast so much better than single turn pots. Just my 2 cents.

liudr: I use a multi-turn potentiometer. It's a pain to turn this thing if I'm no the wrong end of the scale but once I get there I can adjust my contrast so much better than single turn pots. Just my 2 cents.

thanks, I have a multi-turn 10K, so will use that.