[Brightcolours]

Front glass is usually not a thin slab of easily breakable glass, so a broken filter is not an indication to what would have happened to the front element, though. Personally, I do not like the idea of sharp shards of broken glass scratching the front element, so I am not someone to put filters on as standard protection. Thin slabs of glass just do not provide much protection other than touching.

 

Some tele lenses really do not like protective filters, for some reason they shoot OOF with them. I have seen a number of posts complaining about that, but I do not know why it happens.