The Watson Alpha Tropen (Tropical) is a tropical-pattern plate camera, a body style produced for use in hot and humid climates where teak or mahogany construction with brass fittings was preferred over leather-covered wood. It is a collector-grade item rather than a working photographic tool today.

Auction evidence for the Alpha Tropen is thin: a single UK saleroom record from 2001 shows a hammer price of £293, and with no further sales tracked since, the model's value today is difficult to anchor with any precision. As with other tropical plate cameras, condition of the woodwork, brasswork and bellows tends to drive what an example sells for at auction.