Delay only if app not already open


I want to create a new Preview file from the clipboard, having copied it from another app using a Touchbar button.

Easy enough if Preview is already open but, if it's not, then I've had to add a 1.5 second delay to give Preview time to open. Which works just fine.

Problem is that the delay is still there if Preview is already open.

Not really a biggie - I can live with a 1.5 second delay but it'd be nice if the delay could be dispensed with if Preview is already open.

Can this be done outside of Applescript?