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Pictures taken under special light condition

OP coolmingli

11th July 2014, 05:08 AM   |  #1  
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I was in Pandora shop with my wife today, I took some pictures and notice there were some black shadow lines on the pictures, when I start the default camera app, I noticed these lines were rolling across the screen, the store has LED spot lights on the ceiling, pictures taken outside the store were fine.
I try reboot the phone but still the same. I am not sure if it is a hardware issue or software issue.
Pictures taken with my wife's M8 were fine.
11th July 2014, 07:08 AM   |  #2  
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Sounds like an issue with the person operating the camera not knowing about the relationship between shutter speed and the frequency of cycling lighting.

You'd need to use a camera app that lets you set shutter speed to ensure you get even exposure/color under cycling lighting(changing ISO can give some control over shutter speed if camera app doesn't support setting shutter speed-most don't).

Unfortunately LED lights usually have drivers that don't follow the frequency of the AC input power so you may not be able to pick multiples of 50/60hz(depending on your region).

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11th July 2014, 07:18 AM   |  #3  
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Quote:
Originally Posted by lovemyram4x4

Sounds like an issue with the person operating the camera not knowing about the relationship between shutter speed and the frequency of cycling lighting.

You'd need to use a camera app that lets you set shutter speed to ensure you get even exposure/color under cycling lighting(changing ISO can give some control over shutter speed if camera app doesn't support setting shutter speed-most don't).

Unfortunately LED lights usually have drivers that don't follow the frequency of the AC input power so you may not be able to pick multiples of 50/60hz(depending on your region).

Sent from my D6503 using Xparent Red Tapatalk 2

That is interesting, how do I know the frequency of cycling lighting? Are you saying I should set the shutter speed a bit faster ? The lines rolling in the preview screen before pictures were even taken?
11th July 2014, 07:49 AM   |  #4  
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With LED lighting you often won't have any idea what frequency it cycles so you'd need to use trial and error. There's a reason why photographers prefer to not shoot under light sources that cycle, especially if it's the primary light source.

Cycling lights can also cause issues with uneven wight balance as well as exposure. Choosing shutter speeds that allow the lights to have full cycles gives best results.

Slower shutter speed will usually be better(likely why the M8 did better under those LED lights-slower lens & possible set lower ISO) since lights can fully cycle possibly multiple times(depending on how slow). Really high shutter speeds can also capture an even exposure but may have issues with wight balance if the lights color temp varies while cycling(I'm not sure how LED lights are with this but florescent light color temp can vary a lot).

I usually don't bother worrying much about not getting a perfect shot under these types of lighting since it's usually just a snap shot, if a wanted to take a good photo I wouldn't be uses this type of light as primary light source(I also wouldn't be using my Z2, although that's because I have proper camera gear but I understand some peoples best camera is their camera phone or as the saying goes the best camera for the shot is the one you have with you).



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11th July 2014, 08:01 AM   |  #5  
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Quote:
Originally Posted by lovemyram4x4

With LED lighting you often won't have any idea what frequency it cycles so you'd need to use trial and error. There's a reason why photographers prefer to not shoot under light sources that cycle, especially if it's the primary light source.

Cycling lights can also cause issues with uneven wight balance as well as exposure. Choosing shutter speeds that allow the lights to have full cycles gives best results.

Slower shutter speed will usually be better(likely why the M8 did better under those LED lights-slower lens & possible set lower ISO) since lights can fully cycle possibly multiple times(depending on how slow). Really high shutter speeds can also capture an even exposure but may have issues with wight balance if the lights color temp varies while cycling(I'm not sure how LED lights are with this but florescent light color temp can vary a lot).

I usually don't bother worrying much about not getting a perfect shot under these types of lighting since it's usually just a snap shot, if a wanted to take a good photo I wouldn't be uses this type of light as primary light source(I also wouldn't be using my Z2, although that's because I have proper camera gear but I understand some peoples best camera is their camera phone or as the saying goes the best camera for the shot is the one you have with you).



Sent from my D6503 using Xparent Red Tapatalk 2

Thanks for the replies, I dont usually take photos under these light conditions, I just want to make sure that my z2 camera is not broken or something.
11th July 2014, 11:17 AM   |  #6  
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Quote:
Originally Posted by lovemyram4x4

Unfortunately LED lights usually have drivers that don't follow the frequency of the AC input power so you may not be able to pick multiples of 50/60hz(depending on your region).

Shutter speed of his photo is 1/320 s at 50 ISO so the display was adequately lit as you would expect.

No way to set shutter speed directly only indirectly.

Just have to play with exp comp to avoid it.
Last edited by One Twelve; 11th July 2014 at 11:24 AM.
11th July 2014, 12:33 PM   |  #7  
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I noticed that too on my phone..after some seconds (10-15) it turns again into normal ..strange..

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