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I have a Canon 60D and recently bought a Canon zoom lens EF 24-70mm 2,8L USM. Bright colours seem to "glow" or are blurry when I take photos. It does not seem to be blurred because of movement or focus. I am a amateur and consider my self a beginner so this might be a easy question. I will show a photo with this "glow":

Glowing photo 1

Glowing photo 2

Szabolcs
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Sölvi Vignisson
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    I'm not seeing the glow. – Olin Lathrop Feb 09 '15 at 14:10
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    Yeah, I'm not seeing what you mean either. Could you describe more specifically what you are seeing and where it occurs in the images? – mattdm Feb 09 '15 at 14:34
  • have you tried it on a second monitor or someone else's computer? it could be your monitor is mis-adjusted and too bright. – chuqui Feb 09 '15 at 15:50
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    viewed at full size, i believe i can see what you mean. could it be that your lens was smudgy/foggy? – ths Feb 09 '15 at 16:04
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    To me, it looks like you're on EV+1 - these look slightly over-exposed. It's easy to accidentally set that exposure compensation. – Jasmine Feb 09 '15 at 16:44
  • The out-of-focus background also appears to have some color fringe, which normally shouldn't be there. Are these unprocessed images straight from the camera? I miss some exif info I'd expected to be there. – agtoever Feb 09 '15 at 17:35
  • I did not realise at first that these were full-size images. Right-click on each photo and select "View Image" to see the image fill the browser window. Now I definitely see the smudgy, oily look described. – Bobulous Feb 09 '15 at 20:49
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    Do you have a protective filter on the front of the lens? – mattdm Feb 10 '15 at 01:07
  • Can you please post the EXIF info such as shutter speed and aperture? I think that might help figuring out what's causing this. To me it looks like you might be shooting "Tv" mode and you're using a slightly slower shutter speed than you need to get a decent shot – Muhammad Usman Feb 10 '15 at 19:28
  • This almost looks like the USM is malfunctioning, and we are getting tiny blurs from the autofocus. –  Feb 11 '15 at 19:01

3 Answers3

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The first shot is front focussed and looks like it was shot wide open, so a lot of the main part of the image is out of focus, which can result in glowy halos around highlights.

However the effect is more extreme than I would expect, so my guess is the front element is dirty/greasy. It also looks quite a bit like spherical aberration to me which would indicate that there is something wrong with the lens, e.g. it has taken a knock and some elements are out of alignment.

Matt Grum
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The lens your are using and how clean it is are heavily contributing, but the basic answer is how wide open you are shooting, the increased angle is allowing heavy light scatter present in the shooting environment to blur highlights.

xiota
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orbatos
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Many lenses with faster apertures (F2.8 and faster) "glow" when used wide open, especially in bright light with high contrast. It is likely associated with spherical aberration and is typically reduced or completely gone when the aperture is closed a stop or two. Increased familiarity with the lens' behavior and characteristics will allow you to predict when the glow will and won't be present. You will then be able to select aperture to match your artistic intent.

The glow in your pictures is very mild, and I would expect it to be absent at F4. Since these pictures were taken outdoors in apparently good light, you should be able to stop down even further to F5.6 or F8, where lenses tend to have optimal sharpness. The subjects appear to be a considerable distance away, so there is no need to use wide apertures for background blur.

Consider reserving F2.8 for when you need the additional light gathering ability or when you have clear artistic reason for its use. Glow contributes to a lens' character.

Steinheil-Munchin Cassarit 50/2.8

xiota
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