kymarto Loc: Portland OR and Milan Italy

This is simply not true. A CPL is, for all intents and purposes, simply a linear PL that circularly polarizes the light after the fact in order not to affect a camera's AF and metering systems. If you set your camera full manual and compare the effects of the two you will find no difference whatsoever, if the front linear polarizing element is the same.

I can only repeat that a CPL is simply a linear PL that repolarizes the light circularly after the linear polarizer has done its work on linearly polarized light such as that of the blue sky.

If you circularly polarize the light first it has no effect. You can check this by reversing the filter. That will circularly polarize the light of the sky first, so that the linear polarizer now behind the quarter wave plate will have nothing linear to polarize.

Bultaco Loc: Aiken, SC

Crop in camera

Thomas902 Loc: Washington DC

Wingpilot I have the Tokina 11-16mm f/2.8 AT-X PRO lens (Nikon Mount) in the older version which requires the screwdriver type in camera motor. The Tokina Lens hood (tulip shaped) is the BH-778 and is specifically designed to work with this lens. BTW there is only one orientation in which the BH-778 can be attached, that being to work in harmony with the rectangular aspect of a DSLR.

Make no mistake, this lens is at the top of DxOMark's list for performance/value i.e. it is a superb optic (for what it is). In fact you actually can shoot this on an FX sensor body in full frame (not DX crop mode) at 16mm without pronounced vignetting, albeit edge acuity is not at the same level as with a DX sensor. The optic's image circle is that large and it is simply that good...

You have received much tenured wisdom on minimizing/avoiding flare... Yes below 24mm this becomes a serious challenge...
One bit of advice for knowing when you are possibly in harms way is the age old wisdom that has saved many a motorcyclist life or at least kept them out of harm's way... When piloting a bike and the sun is low in the heavens if you can see your shadow in front of you the oncoming motorist likely can't see you (remember the Royal Air Force phrase "Beware of the Hun in the sun.") This is one of the most famous phrases in aviation history i.e. A cunning fighter pilot will always try to use the sun to blind his opponent. Wingpilot the inverse holds true shooting extreme wide angle glass... Shoot where you can see your shadow directly in front of you... But wait you say, what if it's not happening? Well you are a two legged animal... MOVE to the optimum position to make the capture... Remember if it were easy any one could join the ranks of Ansel Easton Adams... who btw said "You don't take a photograph, you make it." The sooner you get your head around this pearl of wisdom the quicker your rise within the industry.

Next issue... Polarizing filters for wide angle optics are not germane... period! I assist quite a few commercial architectural photographers in my market and without exception they all use graduated filters to tame bright sky when capturing with wide angle optics... these are large thin sheets which fit into rotation filter holders and allow for the graduated filter to be shifted up/down to perfectly match the skyline... They also bracket the hell out of the scene since they use advanced HDR software to tame dynamic range...

If you are using polarizing filters on a wide angle lens you are not optimizing your results... especially since the darkening/deepening effect will be more pronounced in an angle of view less than the "wide" angle of view of your optic...

Bottom Line? I shoot the Tokina 11-16mm f/2.8 AT-X PRO lens (Nikon Mount) on a D7200 and cherish it's stellar results... and at a fraction of the weight/cost of the Nikon AF-S NIKKOR 14-24mm f/2.8G ED Lens which Nikon wisely DID NOT provide filter threads... They got this right!!!

colin64 Loc: lsle of islay Scotland

If you use photoshop take 2 exposures, on the second one cover the sun with your finger/hand even if your finger/hand is in the shot then using masks blend out the flare. Works every time.

martinfisherphoto Loc: Lake Placid Florida

It was mounted correctly, if it's not in the right position you will see it in the photo, been there, done that. Nothing wrong here, lens known for this nasty flare. I use my hand as an extra shield when the sun is in the photo. I really enjoy my Tokina 11-16mm an excellent lens, just have to work around this flaring problem.