filter
- Thread starter gboy
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I've never seen the point in covering that quality of glass with more glass. I don't use protection filters on any of my lenses and I have several L lenses. Never scratched any of them neither just need to be careful.
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What do you think is going to scratch the lens?
Glass is very, very hard. It is harder than steel and quite difficult to scratch. One of the few things that can scratch glass is - more glass (or silica, what glass is made from). Sharp chunks of silica are quite good at scratching glass.
In photography there are two sources of silica that can damage a lens. The first is quartz, the main ingredient of most sands and also found in dust. Scraping a quartz grain across your lens (often with a cleaning cloth) is a great way of scratching your lens, so always start your cleaning by using a rocket blower to remove the stuff first.
The other main source of sharp silica is fragments of broken 'protective' filter. The sheets of glass can be easily shattered into shards of shrapnel, all of which are perfect for gouging scratches is the very lens it was supposed to be protecting.
Generally speaking, rather than expecting a filter to protect your front element you should be taking sufficient care of your lens not to need the filter in the first place. However, there are one or two exceptions in my experience. If, for example, you intend taking photos at certain motorsport events where flying stones or shale is a distinct possibility (such as motocross, rallying, or speedway). Then it would be a sensible and worthwhile precaution.
Glass is harder than steel, eh! That's only in your dreams ... not in real life.
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Really?
Hmmm, I must have dreamed everything I learned when I studied geology, especially the bit about how to use Moh's Scale of Hardness. Moh's scale lists various minerals in order of hardness, with talc at the bottom (1) and diamond at the top (10). Steel has a hardness of 4-4.5; glass is 5.5; Quartz is 7.
But don't believe somebody who has actually studied the subject, try it for yourself. Get a clear glass bottle and try to scratch it with a steel knife. You may make a mark, but it will be easily wiped away.
LINK
I'm not talking about your fanciful theoretical geologists crap. I'm talking real life here.
For a more practical experiment you will need the following:-
1. a pane of window glass
2. a sheet of steel of equivalent thickness
3. one house brick
Method
Throw the house brick at each in turn using similar force. Note than whilst the impact against the pane of glass causes the glass to shatter, it merely bounces off the steel plate without so much as leaving a dent. What conclusions are you able to draw from this basic experiment? Go on .. have a guess.
For a more practical experiment you will need the following:-
1. a pane of window glass
2. a sheet of steel of equivalent thickness
3. one house brick
Method
Throw the house brick at each in turn using similar force. Note than whilst the impact against the pane of glass causes the glass to shatter, it merely bounces off the steel plate without so much as leaving a dent. What conclusions are you able to draw from this basic experiment? Go on .. have a guess.
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Er, that you don't know the meaning of the word 'hardness'.
According to your experiments rubber is harder than glass. As is plywood.
Oh, and paper!
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I got sucked in by Jessops with my first two lens purchases. They insisted that to buy their protective filters was essential to protect my lenses and I took them at their word and parted with more cash.
After a while I began to ponder the point of buying decent optics only to shove a cheap filter on the front and having done a bit of research on here I followed the general opinion and stopped using them and my lenses remain unscratched. As others have said, take care of your lenses, particularly when cleaning them and you should be fine.
As has also been said in this thread, it does also depend on what you are shooting. I cover children's footy and am always in close for the (non-alcoholic) champagne drenching that the cup winners do. I have always used my kit lens for this as a precaution because splashes do fly around but a couple of seasons ago I got a champagne blast full on and so those Jessops filters are now proving useful after all
After a while I began to ponder the point of buying decent optics only to shove a cheap filter on the front and having done a bit of research on here I followed the general opinion and stopped using them and my lenses remain unscratched. As others have said, take care of your lenses, particularly when cleaning them and you should be fine.
As has also been said in this thread, it does also depend on what you are shooting. I cover children's footy and am always in close for the (non-alcoholic) champagne drenching that the cup winners do. I have always used my kit lens for this as a precaution because splashes do fly around but a couple of seasons ago I got a champagne blast full on and so those Jessops filters are now proving useful after all