Although there is a “right to light” it is not as simple as most people believe. The entitlement to light only applies to daylight in general -there is no right to direct sunlight. There is only a right to a particular level of light which is normally less that most already receive. The law is not very clear as to how trees affect this right. It is complicated by the fact that trees grow over a period of years, and that most trees don’t have leaves for part of the year. There is no right to light in a ”pleasure” garden. If trees obscure a view then you have no right to that view. The same is true if trees are removed and reveal, say, a building or view you’d rather not see.
If your neighbour’s tree is causing problems, the first step is to talk to them. They may not even be aware of your concerns. Give them the chance to put things right and look for a solution everyone will be reasonably happy with. If, for example, you are worried about shading, it may be that the tree can be thinned rather than felled. GTF Tree care are happy to mediate with your neighbour on your behalf to achieve a mutually agreeable solution will almost certainly be preferable to a lengthy, costly and bitter legal battle.