Circular or Linear Polarising Filter for Digital?

Hi all,

I am a bit confused on the polarising filter issue. As most know there are two polarising filters one is linear and one is circular.
Could someone please explain what the difference is (other then in price) as it seems that the linear one is recommended for 35mm and the circular one is recommended for Digital.
But where is the difference? I still got a very good B/W linear from my 35mm days but what would be the difference if I use it on digital.
TBH I tried it and honestly can not see anything out of the ordinary and it seems to work fine in any way.
Am I missing here something?

Nothing to do with digital or 35mm as far as I recall. More to do with AF or manual focus cameras. Potential for incorrect exposure and focus.

Interesting, never noticed any problem in this at all. Maybe its more an issue with 'cheap' pol filters?
Thanks for that.

Linear and circular pols work in a different way, nothing to do with cheap vs good quality filters. However a lot of people including myself have not really noticed any problem with linear filters on digital. Even if these was an issue, EV compensation and manual focus are at our disposal.

Info here http://www.bobatkins.com/photography/technical/polarizers.html

I still use linear ones. I've never had any problem with AF using LPs, and I used to believe that there was no exposure issue either, but I've been corrected on the latter.

However, any exposure issues are so small in practice that I've never felt inclined to get CPs.

I suppose if you already have a linear polariser, you may as well stick to it. But for purchase, I would go with the recommendations and buy a circular one.

There is a good article in this weeks amateur photographer (22 Jan) on polarisation. It states that circular polarisation is preferable on DSLRs, mainly because of exposure and foccussing. I beleive this is not an issue with Pentax kit, but may be with other brands.

Davex.

Having just read the above link it seems that I may have to get an circular, just to be on the save side, even I have not noticed any of the given problems so far but it may just come when in need of the picture and then it is too late.
Many thanks for your input, and the link was very informative.

I use LPLs with very few problems.

One thing I have noticed is that LPLs seem to give a stronger effect than CPLs on the same lens. Does anyone else find this?

Pentax produced CPLs particularly for the LX to overcome a metering problem with linear ones.