oh no.. what's happening here?

leftcurl

leftcurl

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Name
Leigh
Edit My Images
Yes
just taken some pics for my oktoberfest challenge. So all shots with 50mm f/1.8 mkii.
All shots are wide open and i'm getting a green cast over one side of the images. Not all the images are like this but probably 1 in 5. I've just tested it at narrower apertures and it seems to go away. Is it a problem with the sensor or lens? :shrug:

#1 f/1.8

Day_101.jpg by leftcurl, on Flickr

#2 f/1.8 - but the colour caste has swapped sides :shrug:

Day_102.jpg by leftcurl, on Flickr

#3 f/2.8 it's faded slightly

Day_104.jpg by leftcurl, on Flickr

#4 f/4 it's virtually gone

Day_105.jpg by leftcurl, on Flickr

#5 f/8 seems ok.

Day_106.jpg by leftcurl, on Flickr

all the pics are SOOC... no pp whatsoever. Anyone shed any light on this?

Thanks in advance.
 
forgot to add... i can't test with another lens until later as all my other gear is at home and i'm at work. Just wondered if it was something someone was familiar with.
 
Were they taken under fluorecent tube light?

It's the flickering of the tubes, which changes in both colour and brightness in phase with the 50cpm mains.

Unless you get lucky with the precise timing of the exposure, at higher shutter speeds you tend get the end of one cycle, and the beginning of the next. Longer shutter speeds, which include several full cycles like say 1/10sec, reduce or effectively eliminate it.
 
I'd guess fluorescent lighting as it doesn't show the full spectrum. Unless it's a shutter problem, but if it is I've never seen one with a colour cast?

Certainly weird though...
 
HoppyUK said:
Were they taken under fluorecent tube light?

It's the flickering of the tubes, which changes in both colour and brightness in phase with the 50cpm mains.

Unless you get lucky with the precise timing of the exposure, at higher shutter speeds you tend get the end of one cycle, and the beginning of the next. Longer shutter speeds, which include several full cycles like say 1/10sec, reduce or effectively eliminate it.
Click to expand...

perfect Richard! That's so logical now i think about it. I have flourescent tubes all over my showroom... and like you say.. when i use a narrower aperture and therefore slower shutter speed it is eliminated!

just tried the camera at home now and there is no issues with any pics here :thumbs:

thanks for that .. you too Bill :thumbs:
 
leftcurl said:
perfect Richard! That's so logical now i think about it. I have flourescent tubes all over my showroom... and like you say.. when i use a narrower aperture and therefore slower shutter speed it is eliminated!

just tried the camera at home now and there is no issues with any pics here :thumbs:

thanks for that .. you too Bill :thumbs:
Click to expand...


:thumbs:

If you photograph a fluorescent strip light, just shooting the actual tube itself, at a range of shutter speeds right up to max and a few shots each time, you'll see all kinds of funny things going on with both colour and exposure as the light flashes along the length. I've got some small tubes under the kitchen cabinets that flicker green/pink, but look quite normal to the naked eye.

As an aside, I've been playing with some fluorecent photo lights (those big 105w curly bulbs) and fully expected them to flicker, at least a bit, but they don't. Very close to full daylight colour too.
 
tis interesting stuff what a camera can pick up, that the human eye can't.

i've sussed my shots now in my showroom... i can't use any shutter speed higher than 1/125, which is fine for what i'm doing. Thanks again.
 
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