In movies, sci-fi is sf. Magic is not sf. Cryptozoology is not sf.
BUT IF sf element is too fantastic then title in synopsis section is noted as FANTASY,
IF the sf element is fantasy version of a thing which already existed in science form, it's not enough. Dinosaurs existed, cave people existed, but without science basis for their co-existence or scientific observation of them it's just not sf,
YET I have looked hard for however-stringy an sf angle and passed as many as possible.
Here are DEFINITIONS useful in using SFFot50s.
All matter/energy in space/time and incumbent forces.
The external in its entirety.
Knowledge about, study of or manipulation of the natural using scientific method.
FICTION (reliant on IMAGINE)
Mental awareness (apprehension) of something not present to the senses or never before wholly perceived in reality.
(IMAGINE--To apprehend things that are not external, or which have not been experienced.)
In SCIENCE FICTION the apprehension is constrained by the scientific method.
Fiction which uses the supernatural, or unreflectively the undiscovered natural, in an exclusive or key way.
Outside of nature, outside of the external; unamenable to the scientific method
Knowledge about, study of or manipulation of the supernatural, with or without affect on the natural.
Fiction which seems to be SF but egregiously faulty in application of science.
[From, classically, an aberrant occurrence, usually biological, taken as sign that something was wrong within the natural order.]
A thing of abnormal form or structure (often unusually large), or which exhibits abnormal or unacceptable behavior or character, particularly if causing fear.
In fiction, apprehension, not necessarily using science, of creatures not acknowledged by science as existing.
An individual example is a cryptid.
To clarify, the presence in fiction of a cryptid does not confer qualification as science fiction.
Cryptids can be categorized as:
1. Distribution anomalies
2. Undescribed variants
3. Survivals of species thought to be recently-extinct, "lingerings" when in historic periods only
4. "Living fossils," whose discovery disproves extinction
5. Natural creatures not known from fossil record but related to known species and natural creatures not known from fossil record nor related to known species
6. Mythical or supernatural creatures or supernaturally altered creatures, with or without zoological basis
7. Hoaxes or misidentifications
SF FILMS AND HORROR FILMS often are lumped together as a commodity, or share characteristics, or can be one and the same. The following definitions should be useful in pondering the status of individual films.
SFFot50s points out dramatic narratives often rely on causing or showing FEAR (see below) reactions for entertainment value; these reactions can come from either sf or supernatural stimuli.
Painful and intense fear, dread, or dismay in the abstract.
Painful and intense fear, dread, or dismay in the concrete.
A sudden or violent mental or emotional disturbance.
Emotional reaction to an apprehended threat and/or autonomic response to a threat stimulus, sometimes causing discombobulation.