# Polarising filter for 18-55 or 50mm/1.8 ?



## AceXe (Jan 4, 2012)

Hello mates,

I'm thinking of bying a new Canon EOS 600D with to lenses for beggining - the kit 18-55 and the 50mm/1.8. I want to buy also a polarising filter for one of the two lenses, because my budget is limited. The one uses 52mm of filters and the others 58mm, I think. If I'm wrong, please correct me. But I can't decide which one will be better choice? To buy the 58mm and use it with the zoom lenses or to buy 52mm for the 50mm? Which one will be more useful?


----------



## EchoingWhisper (Jan 4, 2012)

Always buy the larger one cause they can fit in the smaller ones.


----------



## belial (Jan 4, 2012)

Polarizing filters are going to be problematic on both those lenses as they have rotating elements


----------



## TheBiles (Jan 4, 2012)

You can always get a step-up adaptor to use larger filters on smaller lenses, but 



belial said:


> Polarizing filters are going to be problematic on both those lenses as they have rotating elements


 
This is completely true, and I wouldn't waste my time with them on those lenses. You will throw off the focus when you rotate the polarizer, and vice versa. It's a super pain in the ass. 


--
Sent from my Droid Bionic.


----------



## Big Mike (Jan 4, 2012)

TheBiles said:


> You can always get a step-up adaptor to use larger filters on smaller lenses, but
> 
> 
> 
> ...


No, they won't throw off the focus when they rotate the polarizer...but yes, the whole filter will be rotated when the lens focuses, you the technique will have to be; focus, then adjust filter.

As for the different size filters/lenses....yes, buy the filter for the larger lens diameter.  Then you can buy a 'step up ring' for the smaller sized lens.


----------



## bazooka (Jan 4, 2012)

Another problem with using the 15-55 is that at a certain focal length (I don't know exactly) you will lose the ability to autofocus because the polarizer uses between 1 and 2 stops of light. So if your max aperture at 55mm is f/5.6, then the effective amount of light transmitting through the lens is at best f/8 which means AF no longer works. If the CPL uses 2 stops, it's possible your AF won't work at all regardless of focal length.  You won't have this problem with the 50 f/1.8, but I would argue not to buy that lens unless you have a specific reason for needing it. It's too long on a crop sensor to be a good walk around lens imo. But that's for another discussion altogether...


----------



## TheBiles (Jan 4, 2012)

Big Mike said:


> TheBiles said:
> 
> 
> > You can always get a step-up adaptor to use larger filters on smaller lenses, but
> ...


 
Well, it depends on how smooth your CPL is. It's still very easy to throw off the focus when rotating the filter. 


--
Sent from my Droid Bionic.


----------



## Big Mike (Jan 4, 2012)

I haven't shot with an 18-55mm in a long time, but it shouldn't be too much of a problem...especially because it doesn't have Full Time Manual override, so to move the focus ring (while in AF) they would have to turn hard enough to turn the motor etc.  

It's certainly not ideal, but I wouldn't tell anyone to shy away from a CPL because of it.


----------



## AlphaValues (Jan 4, 2012)

I use a Hoya Digital Pro CP on my 18-55. It can knock the focus off a little, but it's simple to learn to hold the lens in the palm of your hand while rotating the filter clockwise while you adjust the filter.


----------



## KmH (Jan 4, 2012)

AlphaValues said:


> I use a Hoya Digital Pro CP on my 18-55. It can knock the focus off a little, but it's simple to learn to hold the lens in the palm of your hand while rotating the filter clockwise while you adjust the filter.


Amen brother!

God bless the adaptability and manual dexterity of human beings! :thumbup:


----------



## Jeroenofzo (Jan 5, 2012)

Both the canon 18-55 as the 50 have a 58mm thread. If not, you could always buy a step up ring for 52->58. Can't use the hood on the widened lens, but polarizers are pretty clumsy to adjust with the hood attached anyway.


----------



## TheBiles (Jan 6, 2012)

Jeroenofzo said:


> Both the canon 18-55 as the 50 have a 58mm thread. If not, you could always buy a step up ring for 52->58. Can't use the hood on the widened lens, but polarizers are pretty clumsy to adjust with the hood attached anyway.



The nifty fifty has a 52mm diameter.


----------



## Buckster (Jan 6, 2012)

I've been using one of these for over 20 years, and it fits all my lenses up to 77mm:

Amazon.com: Cokin P164 Circular Polarizer Filter: Camera & Photo


----------

