How do actors kiss?

Answer 1

I was "unfortunate enough" to learn this technique while working in a commercial with a beautiful starlet. The actors are placed at an angle that prevents the camera from actually "seeing" the actual kiss. The actors make the head movements of kissing, but the lips aren't actually touching. This is commonly referred to as a "Hollywood Kiss".

(addition)

Not to say the above answer is wrong, for there are certainly times when this technique is utilized, but there are obviously plenty of times when the viewer/audience has full visibility of the kiss, and in those cases, it's as simple as professionalism. The actor/actress is professional and has to perform said act making it convincing, but... no tongue, unless the part calls for it.

Answer 2

..................... wat.

C'mon kid, are you screwin' with me? If you aren't, well... Wow... Just Wow.

They do it to ACT out either an act of affection or sexual-conquest/forced or whatnot.

It's not like the actors that kiss in movies go on backstage after the take and start Frenching or making quick, hot monkey-love behind the trailers on their lunch break.

It's just pretendy-time. 'kiddo'.

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