Can you prevent chromatic aberration

Big_Bill

Big_Bill

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317
Name
William
Edit My Images
Yes
Hi again all,
I have been playing round with Lightroom 2 tonight and it reminded me about an issue I have been having.

On some of my photos (and I say some because I can't find a common pattern, never the same lens, ISO, Shutter Speed etc...) I seem to get a red fringe around the subject.

I had a google and what I'm getting seems to be what is described as chromatic aberration.

Can you do anything to stop this or is it a consequence of using a low end camera/lens combination?

Cheers for your help
 
CA usually occurs where you have a big difference in contrast between subject and background.
It's more noticeable on cheap lenses as they tend not to be coated to minimize this. The only real answer would be to invest in better grade lenses

HTH
 
GarynLea said:
CA usually occurs where you have a big difference in contrast between subject and background.
It's more noticeable on cheap lenses as they tend not to be coated to minimize this. The only real answer would be to invest in better grade lenses

HTH
Click to expand...

That's not really true, lots of PP software has options to reduce CA and since it's pretty easy to target fringing they work pretty well. ACR is a good example.

I don't know about lightroom because I've never used it, but I'd be surprised if it didn't have the same functionality.

Does this happen with specific lenses?
 
Unless all your lenses are susceptible the CA then I suspect you're seeing purple fringing rather CA.
Typically CA is a lens issue where the light's component colours are refracted to end up focussed on different planes.
Purple fringing has a similar cause but is attributed to the micro lenses on the sensor.

Bob
 
I will admit that I see it more on the Kit 18-55 than I do on my 50 prime.

If I can, I wanted to try to avoid relying on editing to get rid of it, but if the only way to resolve it is with better glass, that's the way I am going to have to go for now.
 
Cheers photon,
Well I'm not in the market (due to budget) for any new glass at the moment but I will keep that in mind when I am shopping.
 
As you have Lightroom 2 you may be able to reduce the effect by using the CA tool in the develop module. There is also a defringing option as well. You'll find the CA tool as the last entry on the left hand pane under Detail
 
Cheers chappers,
Just learning lightroom 2 so I will have a play the next time i see the problem
 
CA is more common on wide angles - not much you can do - buy a better lens. LR will maybe reduce it - some of the time.
 
If you use Canon lenses, then the latest version of DPP, versions 3.5 and above, has lens specific CA correction programmes. This is the best way to reduce CA by far.

Richard.
 
Rinaldo1711 said:
something else I've learned (I think) :)
Click to expand...

And here's another thing ;) This website, PTLens, has downloads to correct CA, distortion and vignetting, for hundreds of lenses of all brands. I suspect it is not as sophisticated as Canon's free DPP software, and it also costs $25, but it covers a lot of other lenses. Here:
http://epaperpress.com/ptlens/

Richard.
 
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