Mediates oxidation of farnesol into farnesal, a precursor of juvenile hormone in the corpora allata (CA), the glands that synthesize juvenile hormone. Able to oxidize C(10) to C(15) isoprenoid and aliphatic alcohols. (2E,6E)-farnesol + NADP(+) = (2E,6E)-farnesal + H(+) + NADPH Optimum pH is 10-11. Homodimer. Highly expressed level in the midgut and brain in adult females, and at lower level in the abdominal and thoracic ganglia. High levels are detected in corpora allata (CA), Malpighian tubules and fat body. Belongs to the short-chain dehydrogenases/reductases (SDR) family.