In 2011 the model was sold at auction and fetched 14 000 US dollars.
The underwater miniature effects look like they were shot dry and not in a tank. Small amounts of smoke trail from the tips of the wings, an interesting detail added to the miniature to help make it look like it is streaming silt underwater. A few close up shots suffer from too shallow a depth of field with parts of the model in soft focus. Generally British special effects men have to work across all areas of special effects however of the three credited, Richard Conway became more known for his miniatures work, while George Gibbs was usually associated with mechanical and physical effects and Jack Mills for special effects cinematography. Both Richard Conway and George Gibbs must have been at (or very close to) the start of their feature film special effects careers on this film.
