DPReview.com is closing April 10th - Find out more

Panasonic 7-14 F4 vs Olympus 7-14 Pro F2.8

Started Sep 24, 2015 | Questions thread
Paul De Bra
Paul De Bra Forum Pro • Posts: 12,949
That's actually flare, not typically called CA.
2

Flare (from internal reflections of light inside the lens) is mostly caused by sunlight hitting the front element directly. When the sun is actually outside the frame you can shade the lens with your hand (making sure the hand is not visible in the picture) and eliminate the flare. CA is caused by light being bent differently for different colors. Lateral CA is so very regular and predictable that it can be easily corrected in processing because for the same setting (f-stop, focal lenght and focus distance) the same formula can be applied. Longitudinal CA is harder because it is caused by light from the out of focus background "bending around" the subject. It is therefore mostly seen when a fast (prime) lens is used wide open. It can sometimes be somewhat corrected but may require some manual action as it is not a function of where you are in the frame. Flare is totally dependent on where the sunlight comes from and hits the lens. It results in purple or other colored shapes that are hard to eliminate. The best thing is to just consider them to be artistic artifacts that contribute to the photo. Strictly speaking flare is a color aberration and can be called CA but it is typically just called flare to distinguish it from the CA that is visible as colored fringes around edges.

-- hide signature --

Enjoying the Olympus OM-D E-M5.
Public pictures at http://debra.zenfolio.com/.

 Paul De Bra's gear list:Paul De Bra's gear list
Fujifilm FinePix F200EXR Olympus OM-D E-M5 Olympus E-M5 II Panasonic Lumix G 20mm F1.7 ASPH Olympus M.Zuiko Digital 45mm F1.8 +3 more
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow