Do all lenses suffer chromatic aberration at very wide apetures?

erotavlas

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I just received the 24mm f1.8 Zeiss lens today for my Sony Nex. I just happened to take a photo of a tree against the cloudy sky at f1.8 and noticed purple fringing in the branches. It was quite noticable so I tried reducing the apeture and around f2.2 it went away.

I haven't used any lenses before with such a large apeture, so my question is do lenses have this problem at apetures greater than f2.0 ?
Or does it depend on the lens (i.e. does the problem manifest itself at different apetures for different lenses)
 
It does depend on the lens, but it's an especially hard thing to correct for in wide angles. Lenses named "APO" or apochromatic, are 100% corrected for CA. Some wide angle lenses are better than others, I don't know anything about the one you've got, but there are generally test results available online with CA specs.
 
There's software that can correct much of the CA in post.
 
There's software that can correct much of the CA in post.

Lateral CA is easily and effectively correctable, but longitudinal CA is nearly impossible.

I have a lens that has lateral CA that shows up as red and blue on contrasty vertical lines. I have a different lens that suffers longitudinal CA at large aperture, which manifests as green on highlights in front of the focus plane and purple on highlights behind.

The best solution I've come up for LoCA is to desaturate the magenta channel in the affected area. This obviously only works if you don't need that magenta for something else.
 
Some lenses are almost totally free of chromatic aberration even wide-open. For example, take a look at the Coastal Optic 60mm f/4 lens, which is currently selling for around $4,650.
diglloyd - Coastal Optics 60mm f/4 UV-VIS-IR APO Macro - Overview

The Nikon 200mm f/2 AF-S VR-G Nikkor is another lens that's exceptionally well-corrected for CA. It too is in the thousands of dollars range.
 
Even the new $1,000 Sigma 150 macro is a true APO lens. Don't think I've ever seen a lens wider than 50mm than can boast it however, even though some get amazingly close. (Leica 24mm Summilux...)
 
I have an advantage here since I still teach part-time. Over the course of a couple semesters I get to see a lot of hardware. Mostly the entry and mid-level stuff, but you'd be amazed how many little rich college kids (I teach at a campus out in the rich burbs) have Dads with L series zooms and lenses with gold and green rings around the ends, etc. I had two L series zooms in class last semester -- a 24-105 and a 24-70. So with that in mind I'd answer the OP's question with: Yep, pertty much.

Derrel, that achromat is awesome! If I had one of those I'd go looking for a crime scene to photograph under a black light!

Joe
 
Even the new $1,000 Sigma 150 macro is a true APO lens. Don't think I've ever seen a lens wider than 50mm than can boast it however, even though some get amazingly close. (Leica 24mm Summilux...)

reminds me of this review comparing the Zeiss with the Summilux
you can really see the difference. The Summilux does really well.
Sony NEX-7 Rolling Review

I guess considering I didn't have to shell out thousands of dollars, I'll just post process it out if I ever see it.
 
Even the new $1,000 Sigma 150 macro is a true APO lens. Don't think I've ever seen a lens wider than 50mm than can boast it however, even though some get amazingly close. (Leica 24mm Summilux...)

The 24 mm Summilux-M has noticeable axial CA wide open. A lot of the faster 'APO' lenses, including Leica lenses such as the 180 mm f/2.8 APO-Elmarit R, show axial CA wide open. The slower the lens, the less likely it is to have axial CA wide open.
 
Ysarex said:
Derrel, that achromat is awesome! If I had one of those I'd go looking for a crime scene to photograph under a black light!

Joe

How about the ATM you robbed in order to come up with the $4,650 to come up with the scratch for the lens? That'd be a good crime scene!!! Heh heh heh!
 

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