Hi Mike, well you are asking what seems like a simple question but as with all things plant appearances can be deceptive!!!
We really need more pics of the tree and sctions of the canopy, roots and soil, position in the garden, soil conditions..dry, wet, damp...irrigation regime, mulch yes/no, how much sun and hat times of day..morning afternoon?
Japanese maples have hundreds maybe even a thousand cultivars!!!
Whilst some general rules do apply to them all, certain cultivars are more tolerant of sun scorch than others, some require dappled shade, some full shade....I don't know from the pic what cultivar you have.
Growing JMs is an act of love
, my dad has about 15 different cultivars in his garden in UK and I grew up with his various obsessions in the garden JMs being a big one.
We may be able to offer useful advice to you if you give us more info...but there are numerous excellent garedn web sites you should also post in that specifically deal with Maples-Acers, and JMs.