Hood is useful to block out flare but most of us use the uv to protect the expensive lens from damage. However, someone advised me not to use UV filter as it degrads the quality of the photo. is that true?
for an extreme example.
take a piece of glass and look through it
now take another piece of glass and out it together with the first piece of glass
now look through it again, any difference?
taking a picture from an open window is always better than from behind a closed window.