Dramatic Greek plays were performed in open-air amphitheaters, built on the slope of a hill. Amphitheaters, whether large or small, provided the acoustics needed for the actors' words and chorus' songs to reach even the back row of seats, since there were no microphones in ancient Greek times. Modern movies are filmed, then showed on screens in movie theaters. Movies are not performed to live audiences, as Greek dramas were.
The costumes of Greek dramas and modern movies are as different as night and day. Greek costumes involve large masks, which identify the character. They are also used as sound amplifying tubes. Most of the masks are tall, to add stature to the actors. They also help indicate the emotions of the character based upon the facial expression of the mask. Modern movie costumes vary depending upon the movie's theme, however, they don't typically involve large masks.
Like modern movies, the Greek dramas also had a soundtrack, which was provided by the chorus. While a movie soundtrack has a combination of sound effects, score and songs by various artists, the Greek drama's soundtrack was the voice of the chorus. The chorus connected the audience and the actors. It also sets the tone and mood of the play, much like a modern movie's soundtrack.
The format of Greek dramas is quite different than the format of modern movies. Greek dramas began with a prologue, a song by the chorus, alternating episodes of the play, choral odes and an ending exodus. Modern movies are not formatted like this. Modern movies usually have three acts, although movies are not segmented into acts with intermissions. The first two acts, which are 75 percent of the movie, are building the plot. The last act begins with a major set back and ends with the climax near the end of the movie.