You can also not spend and just be careful, and learn to clean glass properly. I just can't understand spending £100 on something to prevent /you/ from being an ass and plonking your fingers on the glass. Doh.
As for protection from shocks, well, a thin /hard/ filter will shatter immediately at the slightest shock, and the pieces will be right next to your front element. Do you want small pieces of hard coated glass rubbing against your front element ?
/Lens/ glass doesn't shatter that easily, it's 'soft' glass with a lot of heavy elements in to improve it's refraction index. So it's actually quite hard to break a lens, you could cause separation of groups due to mechanical shock -- but a filter wouldn't help there anyway.
The net is full of stories with "filter saved my lens" (ie when the lens was dropped etc) but actually in these stories, what happened is these guys were /lucky/ that the shatered pieces of filter glass didn't go and mangle the front element. THATS the true story there.
So, there are zero reasons to use a (non pictorial) filter. It's an urban legend, kept on an on by 1) manufacturers of filters who make a HUGE amount of money on snake oil 2) the desperate need for photographers to accesorise. Snake oil makes you feel better therefore it /has/ to be good.
Just calculate it; look at the price of a 'super duper' filter versus the price of a great /lens/ like for example, a Canon 85mm f1.8 (£200+). The lens is worth barely 3 to 4 'filters'. Doesn't it sound /wrong/ to you ?
As for protection from shocks, well, a thin /hard/ filter will shatter immediately at the slightest shock, and the pieces will be right next to your front element. Do you want small pieces of hard coated glass rubbing against your front element ?
/Lens/ glass doesn't shatter that easily, it's 'soft' glass with a lot of heavy elements in to improve it's refraction index. So it's actually quite hard to break a lens, you could cause separation of groups due to mechanical shock -- but a filter wouldn't help there anyway.
The net is full of stories with "filter saved my lens" (ie when the lens was dropped etc) but actually in these stories, what happened is these guys were /lucky/ that the shatered pieces of filter glass didn't go and mangle the front element. THATS the true story there.
So, there are zero reasons to use a (non pictorial) filter. It's an urban legend, kept on an on by 1) manufacturers of filters who make a HUGE amount of money on snake oil 2) the desperate need for photographers to accesorise. Snake oil makes you feel better therefore it /has/ to be good.
Just calculate it; look at the price of a 'super duper' filter versus the price of a great /lens/ like for example, a Canon 85mm f1.8 (£200+). The lens is worth barely 3 to 4 'filters'. Doesn't it sound /wrong/ to you ?
