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03-04-2016, 07:57 PM   #16
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I don't see any odd difference.

---------- Post added 03-04-16 at 10:07 PM ----------

Maybe doing some tests with Spot metering images to see if whatever you have noticed persists may tell you if it is related to your metering mode. I really did not notice anything odd though, as I mentioned..

---------- Post added 03-04-16 at 10:13 PM ----------

You could also check to see if you have "Highlight Correction" or "Shadow Correction" on, though it may not be completely relevant.

03-04-2016, 08:13 PM - 1 Like   #17
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QuoteOriginally posted by C_Jones Quote
I don't see any odd difference.

---------- Post added 03-04-16 at 10:07 PM ----------

Maybe doing some tests with Spot metering images to see if whatever you have noticed persists may tell you if it is related to your metering mode. I really did not notice anything odd though, as I mentioned..
Click through on one of the second set of images and page through the series on Flickr. There is obvious variation of about 1 stop (brightest to dimmest) through the series. All photos in the series were metered to the same EV using matrix metering.

There is a common problem associated with fluorescent and LED lights and to a lesser extent with incandescents. None of those sources emit true continuous light. If shutter speeds are high enough and the bulb frequency low enough, the photo may be over or under exposed depending on the timing to peak or trough intensity. A similar problem exists with stadium and arena lighting.


Steve

Last edited by stevebrot; 03-04-2016 at 08:26 PM.
03-04-2016, 08:27 PM   #18
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QuoteOriginally posted by stevebrot Quote
Click through on one of the second set of images and page through the series on Flickr. There is obvious variation of about 1 stop (brightest to dimmest) through the series. All photos in the series were metered to the same EV using matrix metering.

There is a common problem associated with fluorescent and LED lights and to a lesser extent with incandescents. None of those sources emit true continuous light. If shutter speeds are high enough and the bulb frequency low enough, the photo may be over or under exposed depending on the timing to peak or trough intensity.


Steve
Wow, that's probably it! The lights in the photos are LED.
03-04-2016, 08:32 PM   #19
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QuoteOriginally posted by dcpropilot Quote
Wow, that's probably it! The lights in the photos are LED.
You might want to switch to M mode at a lower shutter speed and see if you still get the variations. Follow up tomorrow with a burst of open sky exposures at various shutter speeds to rule out shutter issues.


Steve

03-04-2016, 08:38 PM   #20
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I had thought that the type of lighting may be an effect for the event images (gymnastics) that were mentioned. I was referring to the images in this thread when I did not see anything odd. You may be right about the effect, especially with the lights (that I have seen) in gym atmospheres/large buildings.

Last edited by C_Jones; 03-04-2016 at 09:26 PM.
03-04-2016, 10:03 PM   #21
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Yep...what stevebrot said. I deal with a strangely similar 60 Hz issue at my work in a neuroscience laboratory (60 Hz artifacts in USA, 50 Hz everywhere else). Probably a pointless question, but did you use a lens hood?
03-05-2016, 05:49 AM   #22
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QuoteOriginally posted by ldj4549 Quote
Yep...what stevebrot said. I deal with a strangely similar 60 Hz issue at my work in a neuroscience laboratory (60 Hz artifacts in USA, 50 Hz everywhere else). Probably a pointless question, but did you use a lens hood?
For my gymnastics pics earlier in the day, I was using a lens hood. I was using the DA 50-135, 77 ltd, Sigma 70-200 HSM II, and was experiencing the same issue using all three lenses. For the sample pics I posted earlier, I was using the 50-135 without a hood.

---------- Post added 03-05-2016 at 07:57 AM ----------

Here are some pics from yesterday's gymnastics meet using the FA 77 with the hood extended. A huge variance between the first and second photos (looking at the skin tone and white wall in the background). The pics were taken less than a second apart.






Last edited by dcpropilot; 03-05-2016 at 06:04 AM.
03-05-2016, 10:56 AM   #23
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The obvious "control" to confirm Steve's likely correct conclusion would be going out in daylight. You know, that Sun thing. Pretty sure that's entirely continuous lighting.

03-05-2016, 11:27 AM   #24
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QuoteOriginally posted by ScooterMaxi Jim Quote
The obvious "control" to confirm Steve's likely correct conclusion would be going out in daylight. You know, that Sun thing. Pretty sure that's entirely continuous lighting.
Thanks! I'll give it a shot.
03-06-2016, 05:50 PM   #25
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I was able to shoot some photos earlier today using sunlight. The problem is definitely gone in continuous light (such as the sun), so those LED and fluorescent lights are definitely a challenge. Thank you everyone for your help!
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