do you have to use a dedicated airbrush compressor or can a regular shop compressor be used?
As mentioned, air is air.
But you need to give the air tool (in this case, an airbrush), the 'right' air.
And an airbrush needs air that is :
- Clean, no oil or anything else in the air except air.
- Dry, no water (liquid OR vapor) in the air
- Enough CFM to enable you to run the airbrush (usually not a big deal on this one)
- The correct air pressure for the task at hand (again, usually not a big deal but you do need a more than half-way decent pressure regulator as having the air pressure vary while spraying can mess things up.)
A 'small' diaphragm type airbrush compressor is (usually) 'enough'. Almost any home shop compressor is more than enough air pressure and cfm, you just have to filter and dry that air.