First, the yellow of the hps is distorting the true color of the leaves. When I assess my plants I look at the petole, leaf and stem.
What it looks like to me...
Overwatered- petoles arche or curve downward and so do the blades of each leaf. Almost like the tips of each blade have a weight pulling them down. Petole will almost look like it could spring back up, (If the weight were removed) high osmotic pressure
Underwatered- petoles hang or droop downward. The leaf will have a limp and lifeless look and feel to it. Much more drastic than overwatered. Very low osmotic pressure
Nutrient deficiency indicators - dots, blotches, yellowing/ dead leaf tissue, tips of leaves hook up/down, leaf veins/branch stems, petoles turn red
pH indicator - usually twisting leaf blades but a sensitive plants can show nutrient deficiency symptoms and decline quickly where as a vigorous plant may just twist and show random chlorotic/necrotic blotches but keeps pushing on. Also can resemble some degree of overwatering.
High sodium in soil- leaf tip burn, leaves will have obvious nutrient deficiency symptoms, eventually accompanied with heavy chlorotic/necrotic (yellow/dead) tissue, petoles and leafs can resemble overwatered. Stems can get a scab like appearance of the epidermis layer (generally at the base of the branches where they join the trunk)