Attributes of an Academy-qualifying Short Screenplay and Pre-production Elements
There must be conflict of motives between the principal actors in every scene
There must be strong opening visual and/or strong opening action. Oscar winners almost never open with master shots of things, unless the things are exploding. Most winners open with people reacting with strong emotion or action.
The "hook" must be fully engaged not later than the end of the second page.
The plot must be resolved at the end
Although the maximum permissable length is 40 minutes, most qualifiers are much shorter
Must not be a short version of a feature length film. That is, things such as character studies will not work in a short film.
On average, there must be a reveal, a surprise, or a dramatic climax every seven minutes.
Few winners have music tracks. The action carries the emotion without musical prompting.
A period piece increases the marketability of a feature film, but the same is not true of short films. Period settings add cost and risk to short films, and must be period-set for a reason. For example, if race relations were the theme of the picture, then a mid-20th century setting is very important. If the theme is the drug culture, a period setting is not important to the story.
The planned average shot length can deviate from the feature film average of six seconds, but only for good cause. "Dead air" is not good cause.
Production and Post-production Values
Sound must be impeccable. This usually means that most dialog has been replaced. All elements of sound must be present (no omitted elements of sound corresponding to the visuals)
Acting must be believable. If belief cannot be suspended, the film will fail.
Emotions, beliefs and thoughts need to be discernable from the action. That is, the actors' bodies and motives must be natural and synchronized.
Planning of the visuals must be comprehensive and not ad-hoc. For example, wardrobe selection must reflect the personalities of the characters and their roles in the story.
Visuals must not impair the story-telling:
Lighting plan must be generated to match the storyboards, the cinemagraphic style, the action and the mood
Camera gags don't belong in a narrative piece. Reserve those for art films.
Details must be readable by the audience, for the given exhibition medium. For example, eye lights on shadowed sides of faces must be readable.
Use of shallow DOF should be sparingly used, and never as a substitute for engaging action.
There may not be any detectable color-grading problems, such as can easily occur with electronic cameras in the presence of practical lights.
Any CGI must be invisible. (This is usually beyond the feasible technology and budget of a small film). Lighting, speculars, color and resolution must all match the live action.