# How do I know what filter size fits my lenses ?



## Salah Yousef (Aug 22, 2013)

I have an 18-55mm lens and am getting 50mm 1.8 lens. I am planing on buying filters but I don't know which filter size should I get. How do I know which filter size will fit my lenses ?


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## Don Haines (Aug 22, 2013)

If you look at the back of your lens cap it will have a number like E-67mm. In that case, you would need a 67mm filter.

It will also be written somewhere on the lens or you can look it up on the Canon website.


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## Salah Yousef (Aug 22, 2013)

On my 18-55mm lens cap, it says E-58 that means I have to get a 58mm filter right ?


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## Timothy_Bruce (Aug 22, 2013)

take a look her: 
http://www.usa.canon.com/app/pdf/lens/EFLensChart.pdf


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## viggen61 (Aug 22, 2013)

Salah Yousef said:


> I have an 18-55mm lens and am getting 50mm 1.8 lens. I am planing on buying filters but I don't know which filter size should I get. How do I know which filter size will fit my lenses ?



Many places:

In the lens instructions, specifications

In the camera instructions, specification (If you bought the lens a part of a standard "kit"
Canon's website (or appropriate website if it is a Tamron or Sigma, etc.)
On the lens itself. On the front ring, you'll see a lot of information, like "EF-S 18mm-55mm f/3.5-5.6 IS". There will also be a number set apart with the symbol for diameter: "Ø" such as "Ø 52mm" or "Ø 55"


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## schill (Aug 22, 2013)

See also this thread from a week ago:

http://www.canonrumors.com/forum/index.php?topic=16443.0


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## Salah Yousef (Aug 22, 2013)

Thank's everyone. You guys are useful ;D


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## cdnphotog (Aug 22, 2013)

It might be worth your time to look into "stepup rings". These are threaded adapters which convert a large diameter filter to a smaller diameter lens. So if you had two lenses which take filter size 58mm and 67mm, you would buy the larger size filter and a 58 to 67 stepup ring. Now one filter can be used with both lenses. Not as convenient as two separate filters but certainly less costly since you seem to be just starting out with a SLR system. Good luck.


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## verysimplejason (Aug 23, 2013)

cdnphotog said:


> It might be worth your time to look into "stepup rings". These are threaded adapters which convert a large diameter filter to a smaller diameter lens. So if you had two lenses which take filter size 58mm and 67mm, you would buy the larger size filter and a 58 to 67 stepup ring. Now one filter can be used with both lenses. Not as convenient as two separate filters but certainly less costly since you seem to be just starting out with a SLR system. Good luck.



+1. Just be careful when buying stepup rings. You don't want low quality since it will get stuck to your lens even if just a little bump occur.


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## Jim O (Aug 23, 2013)

cdnphotog said:


> It might be worth your time to look into "stepup rings". These are threaded adapters which convert a large diameter filter to a smaller diameter lens. So if you had two lenses which take filter size 58mm and 67mm, you would buy the larger size filter and a 58 to 67 stepup ring. Now one filter can be used with both lenses. Not as convenient as two separate filters but certainly less costly since you seem to be just starting out with a SLR system. Good luck.



Not a big fan of step-up rings, at least not for the "UV Haze" type filter that resides on a lot of lenses. Part of its "job" is to protect the front element from impact and damage. I recently dropped my 70-200 f/4 IS in an asphalt parking lot. The B+W 010 filter shattered but stayed in the ring. I was able to get it off and there was no damage to the front element. There was some internal damage but it would have been worse had the front element shattered instead of a filter.

I suspect I could have had a 67 -> 77 step-up ring and a UV Haze on it. This way I could use the 77mm circular polarizer that I had when I bought the lens, but the impact might well have damaged the ring and left it, at best, stuck in the threads.

I understand the appeal of using step up rings, but the OP is going to have two lenses. If you believe the results at http://www.lenstip.com/113.4-article-UV_filters_test_Description_of_the_results_and_summary.html the Hoya UV filters beat B+W slightly. A Hoya HMC UV filter is $19 at Amazon right now. A 52 -> 58 step up ring is $4. And then he might want a replacement cap. I'd buy two filters. Consider the difference to be full time insurance on both lenses.

Some caveats. This is a new user (based on this and his other threads) and I'm speaking only of protection/UV filters. If he wants to use a polarizer or something more expensive his decision might be different, but by then so might his lens choices.


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