[stepheno]

In a previous thread Andy5452 was asking about filters that protect the lens. Ok - I'll throw a spanner in the works. Why do you want to use a filter? Is it because the guy in the shop recommended one “to protect the lens”? Well he would, after all he’s there to sell you gear. I would question again – why do you want to use a filter?

I use a filter for a specific purpose and to get a specific effect whether it be Circular Polariser, Neutral Grad, Warming or whatever. When I want that effect I put the filter on and when I’m finished I take it off. Ah yes….I hear you say….but what about a UV or Skylight for protection. The bottom line is I do not use filters for protection.

I do know of one or two people who take this view and we are probably in the minority but please indulge me and I’ll explain my thoughts.

1 I use a hood for protection. In the event of knocks, drops, falls etc a hood will be or more protection to your lens than a filter and will absorb the force rather than conduct it to the lens.

2 No matter what quality UV filter you use, you are still putting a layer of glass between the light and the lens, hence some degradation of IQ and certainly increased risk of flare etc. You might say the IQ degradation is not noticeable – maybe not at normal viewing but what if you are making a 100% crop and enlarging?

Would you pay £1,000 for a lens and then put £7.50 worth of glass in front of it. Not me.

3 If you have a UV on your lens do you take it off to use a CP? Or do you think, stuff it, I’ll just pop it on top.

4 I know you are going to say what about protecting the front element from scratches. Well modern lenses are pretty damn tough and I don’t put my lens in any situation that could result in a scratch.

Yes I am extra careful with my kit, lenses particularly. If I’m not shooting for any length of time the cap goes back on but I have yet to be convinced to keep a UV or Skylight on permanently. After all – if it was that crucial then why don’t Canon, Nikon etc just build one into the lens?

Just my twopenneth and thanks for reading.

[Dabhand16]

I'd agree with much of this, except for one thing. The one flaw in Stepheno's risk assessment. He has covered all of the nasty things that can happen to a lens bar one. The unexpected.

I have had the experience of an airbourne substance getting onto my skylight lens protector. I don't know what it was, or where it came from. All I do know is that I never got it off the filter, which I binned.

It has only happened this once, many years ago. OK, the theory of probability says 'that's it - never again', but these things stick in your mind. If it had got onto my lens, I would probably had it looked at professionally, and maybe they could have cleaned it. I'll never know.

If I had a £1000 lens, I'd have a filter on it.

At the time, I used to use the Cockin system for ND, grads etc, and it had a slot for the CP. This was principally because the lenses I used at the time rotated their outer elements in use, so a grad would never stay level if you made any adjustments. The Cockin was so easy to use. The trusy skylight was a screw-thread filter that was on all of the time. I mainly shot transparencies then, and never really noticed any problems when more than one filter was on the camera.

[P-E]

I here what your are saying stepheno but nothing to convince me not to keep a filter on the front of my lenses

I nearly always have a hood on as well as a UV filter........I often shoot with a CP screwed to the front thread of the UV.

[Dave]

Originally Posted by P-E

I here what your are saying stepheno but nothing to convince me not to keep a filter on the front of my lenses

....& not cheap ones either, as I found when I bought some of PE's lenses

[P-E]

Originally Posted by Dave

....& not cheap ones either, as I found when I bought some of PE's lenses

O yes......forgot to say I wouldn't stick a £7.50 filter on the front on any of my lenses.

[Dave]

yep...the dot need to go the right one digit

[stepheno]

Good points you've all come back with. But I suppose it's one of those rare situations where there isn't a grey area. You either do or you don't. Thanks for contributing to the debate.

[Markulous]

Just to add my 2p's worth: I always stick a filter on. Am often out in conditions that are less than ideal - drizzle, rain, wind. So, anything that might help protect the lens a little gets my thumbs up. Also, as a result, can be fairly rough with cleaning/drying. Potentially, might scratch the front - filter OK, lens not OK

[Steve]

Originally Posted by stepheno

In a previous thread Andy5452 was asking about filters that protect the lens. Ok - I'll throw a spanner in the works. Why do you want to use a filter? Is it because the guy in the shop recommended one “to protect the lens”? Well he would, after all he’s there to sell you gear. I would question again – why do you want to use a filter?

I use a filter for a specific purpose and to get a specific effect whether it be Circular Polariser, Neutral Grad, Warming or whatever. When I want that effect I put the filter on and when I’m finished I take it off. Ah yes….I hear you say….but what about a UV or Skylight for protection. The bottom line is I do not use filters for protection.

I use filters for protection and effect, all my lenses are protected with high quality UV filters all the time. I also have CP filters, warm up filters and use the Cokin filter system for graduated and other filter effects.

Originally Posted by stepheno

1 I use a hood for protection. In the event of knocks, drops, falls etc a hood will be or more protection to your lens than a filter and will absorb the force rather than conduct it to the lens.

I also use the Hoods on all my lenses apart from my 17-40L, which when connected to my 20D due to the 1.6X ‘field of vision’ crop becomes useless. Also it as its depth is so thin and it’s a very wide hood it would offer little protection anyway.
What a hood cannot protect against is the elements, wind, rain, sea spray, dust etc. The last two especially will do untold amounts of damage to the special coatings on the front element of your very expensive lens.

Originally Posted by stepheno

2 No matter what quality UV filter you use, you are still putting a layer of glass between the light and the lens, hence some degradation of IQ and certainly increased risk of flare etc. You might say the IQ degradation is not noticeable – maybe not at normal viewing but what if you are making a 100% crop and enlarging?

Absolutely, but this can be minimised by using the best quality filters, that themselves come with special coatings. The loss in IQ on a high quality filter should not be perceivable unless you start ‘pixel peeping’ and as to the cost, if you in the big boy league and buying £1000 lenses then you should also factor in either the cost of a quality filter(s) or replacement/repair for the lens should it get damaged. If the latter two are within your means then I would not hesitate not to use a filter for protection.

Originally Posted by stepheno

Would you pay £1,000 for a lens and then put £7.50 worth of glass in front of it. Not me.

Nope, not me either…but not everyone is in the situation where they can afford not to. If you stretch your budget to buy that expensive must have lens and cannot afford to buy the quality filter to protect it, then as long as you understand the implications of degrading the quality, in my eyes there is nothing wrong with using a cheaper filter just for protection with the view to replacing it with a better one once the funds become available. There is nothing wrong with trying to better yourself and your photography…even if you have to do it in little steps.

Originally Posted by stepheno

3 If you have a UV on your lens do you take it off to use a CP? Or do you think, stuff it, I’ll just pop it on top.

No, here again I always minimise the degradation of quality by swapping the filters over. The only time I stack filters is for effect.

Originally Posted by stepheno

4 I know you are going to say what about protecting the front element from scratches. Well modern lenses are pretty damn tough and I don’t put my lens in any situation that could result in a scratch.

None of us do I would have thought and yet it still happens, the coatings on the front element of your lens are very special and you should be taking steps to protect them as best you can. Using the hoods is a good technique but adding in filters will offer another, different type of barrier protection. There is always that unknown which will sneak up on you and could potentially ruin your very expensive lens.

Originally Posted by stepheno

Yes I am extra careful with my kit, lenses particularly. If I’m not shooting for any length of time the cap goes back on but I have yet to be convinced to keep a UV or Skylight on permanently. After all – if it was that crucial then why don’t Canon, Nikon etc just build one into the lens?

Canon Nikon etc do build protection into the lens, but as always it comes down to cost and marketing. If you want arguably the best protection for your lenses whilst maintaining the ultimate quality all the major manufacturers will happily sell you their own UV/Skylight filter to partner your new toy, these are usually VERY expensive though but will be constructed out of the same quality glass using the same type of coatings. If all manufactures bundled them in with each lens then the costs would raise across the range. As usual since there is no way they would all do that (and some say it is up to the customer to make a choice anyway), then if one took the lead it would only serve to make their prices more expensive than the competition which ultimately is bad business in a very competitive market.

[orangepeel]

Another reason, although it may be a myth, does UV light not damage the sensor?

[Markulous]

Originally Posted by orangepeel

Another reason, although it may be a myth, does UV light not damage the sensor?

My understanding is that sensor not keen on UV but not exposed for any great length of time.

Reminds me of a recent incident. Mate (who probably the most accident prone person I know), slipped and whacked his camera on a concrete post (probably the only concrete post for miles around!).

Sat down to check for damage. Removed lens, as that's what hit, turning it around. Thought "That's funny, I don't smoke". Managed to burn a hole through his jeans as he peered down into front of lens, with sun above his head.......

Reckons that's why so many have probs with shutter (he works p/t for Jessops, poor guy!) - bit of sun through lens onto thin metal shutter; wouldn't take much to distort