greymule Loc: Colorado

Wondering if the use of a CPL adds to C/A?

rmvdw

What is CPL?

greymule Loc: Colorado

Circular Polarizing Lens

SharpShooter Loc: NorCal

Mule, every piece of glass you put on your lens whether cheap or VERY expensive will add to CA. It's not a matter of which one!
Your lenses have a ton of money thrown at them in the form of R&D by the designing maunufacturere to reduce CA's. If they do enough, maybe they can mostly control most CA's but they still exist.
Now you're going to take a cheap piece of $200 glass and stick it somewhere in the element path, maybe in front of the lens or maybe behind the lens. Do you think that filter company spent a million dollars to make sure your particular lens works 100% with their filter......, when your lens did not even yet exist at the time they made the filter?
Filters are used to create a desired effect, NOT, to improve your $10,000 lens.
So in short, yes, that cpl will creat additional CA's. It doesn't matter WHICH filter.
Ok, so some are gonna argue that their über expensive B+H Schott glass thing is better, maybe it is better, but it STILL will increase the native CA's.
That's my story and I'm sticking to it!! LoL
SS

greymule Loc: Colorado

Thanks so much. And yes I have the uber expensive newest B&W CPF. I like the depth of color and lack of reflections with the CPF, but I hate the C/A in higher contrast edges. Oh. Well. Everything in life is a trade-off, eh?

wdross Loc: Castle Rock, Colorado

SharpShooter is correct that any glass, not a part of the original lense design, will increase chromatic aberration. Most of the CA will occur in the corners, but it can cause some loss of color focus even in the center. The thinner the glass, the less the affect. Since CP filters are two pieces of glass sandwiched together, they tend to be thicker than most filters and tend to affect the picture more.
Now having said all that, the affect is normally negligible relative to the need of the filter's effect. And the CA will be more noticeable in wider angle lenses than telephoto lenses due to lense design. The only thing I would do in purchasing a CP filter is get the one that creates the greatest affect with least thickness. There are no other solutions.

martinfisherphoto Loc: Lake Placid Florida

I'm going to disagree on this guys. I use the tokina 11-16mm for landscapes and even though a terrific sharp lens, when shooting into/towards the sun the CA is terrible. I often use a ND filter to help with this. Of coarse the best solution/learn the limitations of your equipment/ is not point the camera towards the light, but sometimes you need the shot.....

greymule Loc: Colorado

Thanks guys for helping out. I guess it's just the limitations of the equipment.

jerryc41 Loc: Catskill Mts of NY

I use Marumi and have never noticed an increase in CA. Sometimes, I'll zoom in during processing just to check. LR has a CA adjustment, but I seldom have to use it. If I have to zoom in to see it, how bad can it be, right? A lot would depend on the quality of the CPL

greymule Loc: Colorado

Armadillo Loc: Ventura, CA

greymule,

I think your answer will come if you make a test of your setup. Recall the type of image you captured when you noticed the CA. Go back and recreate the same type of capture and make two exposures. One with the CPL attached with "0" filtration applied. The second exposure without the CPL attached. Make sure you use the exact same lens, the focal length and Aperture settings are the same.

Michael G

wdross Loc: Castle Rock, Colorado

Armadillo is correct. Most of the time the CA increase is negligible for almost all intents and purposes. But it is always up to the photographer to make that determination. Just because most of the time the change is not noticeable doesn't mean it is not there.

amfoto1 Loc: San Jose, Calif. USA

My experience with the Tokina was that while there's some CA, it's mostly toward the corners and edges and is better controlled in the 11-16mm than in a lot of other ultrawide zooms. If you're seeing a lot, you might want to have the lens checked for any problems, such as a de-centered element (though that's not a common occurrence with the 11-16mm, AFAIK). Or, at the least, try to get hold of some other copies of the lens to compare.

What CA there is seems worst at the widest focal length zoom setting (11mm) and a little less at the least wide (16mm).

The biggest issue with 11-16mm is it's extremely susceptible to flare... so much so I opted for the Tokina 12-24mm instead, used that for some years and eventually got the Canon 10-22mm (which is one of the most flare-resistant UWA).

But they all show some CA, especially at their widest settings and largest apertures. It's just really difficult to get all the colors of the spectrum to align perfectly with ultrawide lenses and especially with more optically complex zooms.

Yes, adding a filter can increase CA.... especially cheap, poor quality filters. And a CPL is a multi-layer filter, so a poor quality one would potentially be even more problematic than other, single layer types of filters of same quality.

A higher quality CPL or other filter is less likely to make much difference in CA.

CA might be correctable in post-processing. Sometimes automatically... sometimes manually. (Depends upon the post-processing software being used.)

kymarto Loc: Portland OR and Milan Italy

I'm going to use this quote to give several answers. First, I have never heard of a normal filter increasing CA to any noticeable degree. Lenses are designed to bend light, and whenever light is bent from a straight path, there is a differential bending depending on wavelength. That's CA. Filters are flat, and do not bend light to any significant degree, therefore there will be no noticeable increase in CA under normal circumstances. Of course anything in the path of the light will affect it to some degree, but we are not talking about anything perceptible, even viewing at 100%, when it comes to decent filters. I suggest the OP post examples at 100% with and without the CPL so that we can see exactly what he is getting. Make me a believer. At the moment I am completely skeptical.

As to the Tokina 11-16: this lens is (in)famous for its extremely high levels of CA and poor flare resistance. Nothing will help that. I got rid of mine for those very reasons. It's a nice lens and sharp, but woe betide any contrast transitions (especially in out of focus background areas) nearing the edge of the frame. No neutral density or other filter will help this. You should do some tests with and without your ND with the camera on a tripod and compare. I think you will find that the ND doesn't really help at all with CA, just as a CPL won't increase it.

GENorkus Loc: Washington Twp, Michigan

Yes but short of large printing, I doubt you'll notice. If you do just post process it out!