The Lizars Challenge Dayspool Stereo Tropical is a tropical-finish stereo plate camera sold by the Glasgow optician and retailer J. Lizars under its Challenge house brand. As a tropical model, it was built with polished hardwood and lacquered brass fittings intended for use in hot, humid climates, placing it at the upper end of Lizars' early-20th-century stereo offerings.

With only a single recorded UK auction result, the price for a Challenge Dayspool Stereo Tropical is best described by that hammer figure rather than a meaningful range: an example sold for £2,880 in 2019. At saleroom level — a wholesale hammer result, not a dealer asking price — tropical-bodied stereo cameras of this era are highly condition-sensitive, with the state of the woodwork, brass, bellows and shutter materially affecting what one is worth today in 2026.