Scratch on filter.

[deudeu]

I bought a 52mm Hoya multi coated UV filter to protect the Kit lens that i originally wanted to get rid off (i am going to keep it and try to make the best with it... it breaks my heart, but sometimes you have to listen to your wallet).

Right out of the box there was a bunch of little white spots on it. So i used my Gitzo air blower to get it off but, probably because of static, could not quite get it. So i proceeded to use my microfiber cloth.

And this is when i felt a little vibration on the glass, you know the kind that gives you chills. I looked and there is a little tiny scratch on the outside of the filter. I haven't taken any pictures with it yet so i don't know if it's noticeable on images.

Here are the questions:
1. Shouldn't it be much more difficult than that to scratch a multi coated piece of glass?
2. Aren't the microfiber cloth designed to prevent this from happening?
3. Could this be the result of a dirty cloth and how often do you wash yours?

Thank you

 

[Tiberius47]

Does the scratch show up in the photos? Put the filter on, set the aperture to f22 or something really high like that, put the lens on manual focus and then shoot a plain blue sky or other plain background and see if the scratcjh appears. if it doesn't, you're pretty well set.

 

[Garbz]

1. Yes but doesn't help if there's a rock or something in the cloth.
2. How by consuming the rock? Make sure it's clean.
3. Never I use my cotton shirts, but only when I haven't been rolling in the dirt.

I doubt a scratch will show up in the photos. I found an F-mount lens one day that looked like it had been attacked by an orbital sander, and it still shot fine. Minor contrast issues though.

 

[chris]

Does the scratch show up in the photos? Put the filter on, set the aperture to f22 or something really high like that, put the lens on manual focus and then shoot a plain blue sky or other plain background and see if the scratcjh appears. if it doesn't, you're pretty well set.

I assume that you are meaning to focus on the scratch, but even at f22 the lens will not focus close enough to show the suface of the filter so this test is useless and anyway unless your normal subjects are just a few millimetres from the from element of the lenses this would not prove anything.

To check the effect of the filter take identical shots of a subject with fine detail with the filter on and with it off and then compare them. It is extremely unlikely that a fine scratch at the edge of a filter will have any visible effect on the image at all. Scratches on filters, and lens elements, will produce overall softening of the image but the scratches have to be extreme before there is a visible effect - check out soft focus filters to see the sort of surface degradation needed to soften an image.