How do I avoid purple fringing?

Foto_Mommy · Jul 20, 2009

I have taken a few photos outside in the sunlight and when I look at them on the computer they have a purple look to them. I found out it is called "Purple Fringing." How can I avoid that happening while shooting outside?

tirediron · Jul 20, 2009

I'm not seeing any purple fringing on your image, however that's likely becuause (1) The imgage is compressed and (2) my work monitor is not the best. If it is true purple fringing, that is a thin purple-ish line usually along white or very light colour borders than there are a couple of things you can do:

-Always use a lens hood

-Avoid shooting into/toward the sun as much as possible

-Buy a better lens (Yes, I know that sounds rather rude, but the simple fact is that the better the lens, the less problematic things like purple fringing, chromatic abberation and other annoying issues will be.

Foto_Mommy · Jul 20, 2009

Thanks

I never really use a lens hood... I guess its there for a reason eh? LOL

musicaleCA · Jul 20, 2009

+1 on the better lens. I think I see a little purple between the white dark feathers on the right hand side. A 100% crop (a crop of the fringing but at 100% zoom) would help to illustrate the problem much better, and the severity of it. There are ways to remove the purple hue in post, but fringing and CA will always result in a loss of edge sharpness.

Josh66 · Jul 20, 2009

I don't really think a hood would make much difference here...

A better lens probably would, but even then - you will never eliminate it all the time.

Stopping down should help too...

High contrast is what is causing it.

Big Mike · Jul 21, 2009

Avoid using the extremes of the lens. This sort of thing is probably more prevalent at the maximum zoom and/or at the widest aperture. Of course, a better quality lens can really help because the designers put in special glass elements to prevent it.

Foto_Mommy · Jul 21, 2009

I am looking into getting better lenses but they are so expensive... cant really afford them with a toddler and baby on the way lol. But thanks for your advice.

musicaleCA · Jul 21, 2009

If you can't get yourself a better lens, no worries. (Kids totally come first.) Try defringing with software like Lightroom. If you can manage the problem in post you'll get more bang for your buck. Or just avoid really high contrast edges (even the best lenses on the market will have some amount of fringing or CA at some point, when that contrast gets great enough).

Josh66 · Jul 21, 2009

I haven't been too impressed with Lightroom's defringing/CA correction... Your milage may vary...

You could try desaturating just the purples, assuming that there isn't a lot of purple elsewhere in the picture it should work OK.

Baaaark · Jul 21, 2009

Okay so try the lens hood. And, even though I have NO CLUE whether or not it would help, you could try a UV filter. I know the indigo and violet colors are closest to Ultraviolet rays on the electromagnetic spectrum and therefore very similar. Maybe it would help. As it is we can barely see violet as a color. Its just within the light rays that we can see. Just outside is Ultraviolet. So maybe a UV filter would help get rid of those stray purples that are quite similar to their invisible brother.

The worst it could do is put you back 10-15 bucks, and even then you'd still have a UV filter for sunny days.

musicaleCA · Jul 21, 2009

That extra piece of low-quality glass and gap of air is liable to increase fringing though. :-/

And O|||||||O, what don't you like about it? Is it not removing CA in some cases? It removes the CA from my 17-85 pretty well, and that lens has frightening CA and fringing. Eugh.

Josh66 · Jul 21, 2009

musicaleCA said:
And O|||||||O, what don't you like about it? Is it not removing CA in some cases? It removes the CA from my 17-85 pretty well, and that lens has frightening CA and fringing. Eugh.

It just never seems to work (well) for me...

Sachphotography · Jul 21, 2009

There really is no way to eliminate Chromatic Abberation. The only way it can be reduced is by upgrading your lenses. Sorry mate. No tool aliv can really get rid of it.