Cheap filters - a cautionary tale.

[Glenn]

So, I take delivery of a beautiful mint condition 300 f4. I add a protective 77mm UV filter, carefully cleaned. I shoot the old petrol pump across the road - my usual test target. I examine the images blown up on my iMac.
What the deuce!(or words to that effect).
Soft! Can't believe it - not with the 300's rep.
Up shutter speed, add tripod, litter carpet with hair. No avail.
Ah? Remove filter. Smiles all round. Sharp.
Have a look at these 100% crops - bearing in mind they were shot through window glass.
I bought filter on e-bay. It's marked "Kenco... Japan". Should be all right? Knock-off? Lesson learned.

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_71A1170 by glennwith2, on Flickr

View attachment 1211094
_71A1171 by glennwith2, on Flickr

 

[TonyW]

Wow, that is soft - sure you did not by a soft focus filter :biggrin:.

A lesson for us all on buying cheap filters for good glass. This one looks like it has been ground down from milk bottle glass (do glass milk bottles still exist?). I used to check filters (UV, colour) by holding over a static subject such as newsprint and gently moving the filter to see if any distortions apparent. If not ground optically flat on both sides then it is quite easy to spot poor manufacture.

 

[Glenn]

Tony, the filter passes the test you mention, which is why I used it in the first place.
I've just been checking prices of 77mm Nikon filters. Ouch! Think I might just go naked and carry a Rocket and Lens Pen!

 

[TonyW]

I know what you mean about the price of filter Glenn from Amazon prices range from £25 to £70:
B + W Filter 77mm UV Filter With Multi Resistant Coating £65 Amazon
Hoya £24.95
Nikon £68

Personal view I do not use filters other than CPL due to potential risk of degrading image (certainly the potential is there with the lesser brands). There is much debate on using (or not) filters to protect the lens and I can see the case put forward by both sides, just my decision to avoid where possible but I would reconsider if I was constantly shooting in bad conditions

 

[IsamuM]

I bought filter on e-bay. It's marked "Kenco... Japan". Should be all right? Knock-off? Lesson learned.

If that ("Kenco") is not a typo, then it's a knock-off. The name of the brand is Kenko and it's a subsidiary of Hoya. In fact, Hoya doesn't sell any filters under its own name in Japan. All of the Hoya filters are sold under the Kenko brand.

 

[RKnecht]

I never use UV filters. A rocket blower and a lens pen are in my bag all the time in case I need them. Using a lens hood, which I always do, helps keep the front element protected. I USE my gear a lot and have never damaged a front element.

 

[MParker]

It's not that some filters don't offer protection, and it's not that some filters don't have quality coatings. Some do and some don't. It's that the protection offered is minimal at best and the coatings on the filter are almost never as good as the lens you're protecting.

For me . . . A windy day on the beach, maybe. Otherwise, no thanks.

 

[Mr. Graceful]

Tony, the filter passes the test you mention, which is why I used it in the first place.
I've just been checking prices of 77mm Nikon filters. Ouch! Think I might just go naked and carry a Rocket and Lens Pen!

Not to stir the pot, but + 1 for this solution.

 

[Glenn]

If that ("Kenco") is not a typo, then it's a knock-off. The name of the brand is Kenko and it's a subsidiary of Hoya. In fact, Hoya doesn't sell any filters under its own name in Japan. All of the Hoya filters are sold under the Kenko brand.

Yes, sorry Isamu, it was a mistake on my part - "Kenko" is what it says.
It must be a knock-off. Whatever it is - it's in the bin!

 

[fishbio]

This topic has come up a number of times and I posted examples from a 300 f4 with cheap filter about four years ago. I had exactly the same experience you did. I bought a second hand lens that came with the filter on it. I thought I'd bought a dud till I took off the filter. I shoot naked!

Larry

 

[Deleted member 4116]

Not to stir the pot, but + 1 for this solution.

I'll stir the pot...STOP USING UV FILTERS! Can't count the amount of photos i've had to ditch because they were destroyed by a UV filter.

I'm extremely careful with my gear and always use a lens hood. The one time I get caught off guard with my gear, I drop my d600 w/ 24-85 attached and the only damage was a broken lens hood. Whew!

 

[Randy]

I have been taking off my hoya super UV's the last few years.....the only time I try to have one on is around salt water

I never had a problem but figured why chance it

 

[Thorsten]

The same thing happened to me, with the very same 300/4, but a top quality filter (B+W X-pro polarizer). I only found out after i came back from a day's shoot. All the image had this smearing, and blooming highlights. iI've sent it to B+W and they replaced it free of charge. The replacement is fine. Maybe they had a bad batch, who knows.

So I learned not to trust any filter without checking it carefully. And I never use UV or "protective" filters anyway.

 

[Lurker]

I'll stir the pot...STOP USING UV FILTERS! Can't count the amount of photos i've had to ditch because they were destroyed by a UV filter. (...)

That would be stop using cheap UV filters. There's nothing wrong with placing a $100 piece of flat, coated glass in front 20 pieces of $100 curved, coated glass. Where people go wrong is by using a $20 filter.

I do agree that filters add, aside from situation where you get a lot of muck flung at the lens (the beach on stormy days, motocross, etc), the physical protection offered by a filter is minimal. In those cases where I hear that "the filter took the brunt of the impact"—no, that's not how physics work. A 20g filter will not take the majority of the impact when a .75kg lens hits the ground. It will shatter, absorbing about 2% of the impact and leave the rest to the lens which will do just fine (or not) at that point. On the other hand, a shattered filter might leave scratches on your front element, so there's that.

But if it makes you feel more secure and lets you take pictures in situations that you wouldn't take pictures in otherwise... by all means, use a filter. Just use a good one.

 

[nuclearjock]

I never use UV filters. A rocket blower and a lens pen are in my bag all the time in case I need them. Using a lens hood, which I always do, helps keep the front element protected. I USE my gear a lot and have never damaged a front element.

^+1 Rich. I damaged the front element of a 70-200 VRII once by slightly impacting a UV filter and having it crack and ultimately scratch the front element. No More. I figure if I can navigate so as not to scratch the front elements of my 200, 300, 400, & 500 VR's, then I should be able to do the same with my other lenses. A lens pen, and sometimes some ethyl alcohol and a micro fiber cloth (as per Nikon) are all that's needed.

 

[Jeff Lee]

Nikon filters on my Nikkors lenses. I've broken a few filters (never hurt the lens btw) and was glad I had them. But I don't seen an optical difference when using the Nikon filters. But I did gasp when I bought the Nikon CP (If you think Nikon filters are expensive look at Heliopan) and a different size B&W CP.

 

[Desmond]

This topic has come up a number of times and I posted examples from a 300 f4 with cheap filter about four years ago. I had exactly the same experience you did. I bought a second hand lens that came with the filter on it. I thought I'd bought a dud till I took off the filter. I shoot naked!

Larry

And you allowed me to use those photos on my blog about cheap filters and bokeh

 

[vindex1963]

B+W oh yea :biggrin:

 

[crashton]

Nikon filters on my Nikkors lenses. I've broken a few filters (never hurt the lens btw) and was glad I had them. But I don't seen an optical difference when using the Nikon filters. But I did gasp when I bought the Nikon CP (If you think Nikon filters are expensive look at Heliopan) and a different size B&W CP.

+1 They have saved more than one lens for me. If using a filter don't cheap out buy a good one, they are worth it.

 

[rvink]

Telephotos magnify any degradation caused by a filter. The same filter used on a shorter lens might look much better. But as others said, I tend not to use a protective filter, unless there is something specific I need to protect the lens from, such as salt spray.