Hi Swamesh,

Are you interested in topics like optical science, lasers, optical communications and so? If yes, you can safely venture to pursue photonics.
Having said that, you won't be getting to study the core and major topics of physics apart from properties of light and its interaction with materials.
Say, if you are interested in nuclear physics, you might consider taking up msc in physics rather than going for a specific course like photonics.
So you need to ponder upon your area of interest.
Your future career areas are equally bright in both. You can go for research and development in both these fields and you can get placed in top companies as well.
Manipal university is considered as a reputed university for their acads as well as placements. Infact it also offers msc in photonics. You can opt for photonics or physics in this university without any hesitation.

Let me know if you need further clarifications.