I have a Kaesmann CP for my 24L. Simple enough to use I thought.
I have to say, its very tough. I pretty much try to use it all the time on the 24 as its my landscape lens of choice and I am trying to get the nice blue sky shot effects with it.
That said, its seems exteremely unpredictable in its use. I get things like over the top looking purple skies or odd greens. Things tend to always just seem a bit 'off' although every now and then I fluke off a nice shot. I find I basically shoot about 3 shots per 'shot' and then pray one of them turns out nice. Through the viewfinder I can see the effect at maximum but dialing it back I really lose any feel for what the end result will be - and what might look great on the little screen on the back of the body means nothing for what it may look like when I actually get it into LR.
So, any tips or tricks? Much appreciated if you have them!
The effectiveness of a CP depends on the angle to the light source. Right angles are the most effective with the effect decreasing as the angle to/from the sources decreases. Shooting into or away from the light source, one typically only gets the stop or so of neutral density except for the CP effect that might obtain in reflection areas. A common problem with wide lenses is that they see such a wide area of the sky that an obvious gradient is visible. My personal preference is to reserve the CP for controlling reflections and use other techniques for managing the density of the blue in skies. Many will disagree .
As I'm sure others will point out, the problem with using a CP on a wide angle lens is the light your camera sees is not uniformly polarized across areas. When light gets diffracted through different substances or off different materials (such as different gas compositions and dust in the air), the polarization angle changes relative to the camera. This results in various effects of the CP on wide sky shots.
I have yet to find a good way to overcome this other than to take the shot without the polarizer at a better time of day where the light / sky color is more what you're looking for. Otherwise, just hope for better air quality but it's pretty much hit and miss.
I'll turn the CirPol to max effect, then back off a bit. The blues will be more uniform for the most part.
The wider you go, the more difficult it is to get a homogenous sky.
I find the problem isn't necessarily the homogenousness, its the odd shifts. I do notice that one side is maybe more blue than another but this is not normally much of a problem. What is a problem is just getting it set so I have a consistent idea of what I might get. It seems almost random. Hence I normally shoot 3 shots of the same thing and hope one of the effects comes out looking ok enough.
That said, on occassino I can see 'bands' where things look very strange. I will post an example once I get home and have access to show you what I mean by that.
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