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Author Topic: Why does the camera take green pictures?  (Read 11306 times)

Offline Atomic-S

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Why does the camera take green pictures?
« on: 20/11/2010 03:30:37 »
Anyone know anything about the Olympus FE-170 camera? I have one that has the following annoying habit: Every once in a while it takes a greenish picture. The greenish pictures amount to maybe 5% of the total, and occur, it seems, largely randomly; however the problem has never been observed when taking photos in full daylight. Also, I have not seen a greenish picture under circumstances where the flash was on "automatic" (which, of course, it normally would be in full daylight); however I do not take many flash pictures. The pictures in question are taken with the flash disabled, which I do because they are usually close-ups, although green pictures have also occurred for distance shots indoors with the flash disabled.


 

Offline RD

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Why does the camera take green pictures?
« Reply #1 on: 20/11/2010 05:46:33 »
The green tint is probably due to fluorescent lighting.
 
There may be a colour correction "white balance" setting on the camera for taking photos in fluorescent light which will avoid the green cast, or a custom setting for white balance in atypical situations. 

Quote
Fluorescent (symbol of a long rectangle or Fluorescent tube): Use this if your photos are too green or under Fluorescent, mercury, HMI or metal halide lights as you might find in street lights
http://www.kenrockwell.com/tech/whitebalance.htm

http://www.wired.com/gadgetlab/2010/11/set-perfect-white-balance-with-starbucks-coffee-cup-lid/
[a two-ply sheet of white toilet paper can also be used over the lens when setting the white balance]


There are free photo editing programmes, (like GIMP or Irfanview ), which will allow you to correct the colour balance of a photo, e.g. remove (or add) a green tint ...


« Last Edit: 20/11/2010 08:31:35 by RD »
 

Offline elfabyanos

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Why does the camera take green pictures?
« Reply #2 on: 26/11/2010 12:11:14 »
An interest thing about white balance is that the camera when it takes an un-balanced photo and gives it a tint could actually be correct - it is our eyes that are wrong. To enable us to function better the brain constantly readjusts it's own white balance (done in an interesting way using push-pull ganglions where two colours are pitted against each other for each area of the image, it is only the relationship between the colours that the brain cares about, not the colour itself), so that white things remain white in appearance even if the ambient light is actually slightly tinted. The colour we see is an illusion, hence why there are so many tricks-of-the-eye out there.

All consumer cameras have automatic white-balance, usually by selecting sunny, cloudy, flourescant etc. Good ones will allow you to do it manually the proper way - by holding a blank sheet of A4 in front of the camera and telling it to adjust to that. This is how professionals do it.
« Last Edit: 26/11/2010 12:17:44 by elfabyanos »
 

Offline maffsolo

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Why does the camera take green pictures?
« Reply #3 on: 26/11/2010 15:50:57 »
That almost looks like night vision...

See if you can setup some infrared light and see if this affects the pictures
 

Offline Atomic-S

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Why does the camera take green pictures?
« Reply #4 on: 29/11/2010 05:18:16 »
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An interest thing about white balance is that the camera when it takes an un-balanced photo and gives it a tint could actually be correct - it is our eyes that are wrong.
Well, I have experienced this in another situation: Taking night pictures by moonlight. The pictures tended to turn out redder than the scene appeared. (Also brighter due to the limits on this camera of adjusting brightness under this condition). I interpreted the redder look to the theory that the eye's night vision is different than its day vision, but the camera's is the same regardless of light level.
 

Offline Atomic-S

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Why does the camera take green pictures?
« Reply #5 on: 29/11/2010 05:21:09 »
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The green tint is probably due to fluorescent lighting
I tend to think not in this case, because green and nongreen pictures have occurred one right after the other in a single shooting session under the same lamp.
 

Offline Atomic-S

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Why does the camera take green pictures?
« Reply #6 on: 29/11/2010 05:41:04 »
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There are free photo editing programmes, (like GIMP or Irfanview ), which will allow you to correct the colour balance of a photo, e.g. remove (or add) a green tint ...
I am looking into this.
 

Offline RD

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Why does the camera take green pictures?
« Reply #7 on: 29/11/2010 06:29:31 »
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There are free photo editing programmes, (like GIMP or Irfanview ), which will allow you to correct the colour balance of a photo, e.g. remove (or add) a green tint ...
I am looking into this.


GIMP is multi-platform, (Linux, Mac OS X, Windows, etc), but Irfanview is only available for Windows operating systems.
Irfanview uses less computer resources than GIMP, (and offers less features), so may be preferable if you have an older computer.
« Last Edit: 29/11/2010 06:31:28 by RD »
 

Offline Ross0aberle

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Why does the camera take green pictures?
« Reply #8 on: 01/12/2010 09:54:20 »
Quote
There are free photo editing programmes, (like GIMP or Irfanview ), which will allow you to correct the colour balance of a photo, e.g. remove (or add) a green tint ...
I am looking into this.


GIMP is multi-platform, (Linux, Mac OS X, Windows, etc), but Irfanview is only available for Windows operating systems.
Irfanview uses less computer resources than GIMP, (and offers less features), so may be preferable if you have an older computer.


GIMP is a bug-fix release in the stable GIMP 2.6 series.Right?
 

Offline RD

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Why does the camera take green pictures?
« Reply #9 on: 01/12/2010 10:00:35 »
GIMP is a bug-fix release in the stable GIMP 2.6 series.Right?

I'm still using 2.4.7 which runs perfectly on windows Vista, I found that more recent releases crash on Vista, but that may be my machine's fault. (It's been about 6 months since I last tried the latest GIMP release so they have may have fixed the Vista problems).
« Last Edit: 01/12/2010 11:02:52 by RD »
 

Offline imatfaal

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Why does the camera take green pictures?
« Reply #10 on: 01/12/2010 10:13:07 »
Just noticed I am using The Gimp 2.2 - maybe time for an update
 

Offline techmind

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Why does the camera take green pictures?
« Reply #11 on: 07/12/2010 21:11:22 »
I don't know anything about the specific camera mentioned, but it is possible that this is just a shortcoming of typical white-balencing algorithms which happens every so often.

If you compose a picture within the viewfinder/display which has a strongly predominant colour (eg magenta) then the camera may tend to overcompensate and make the picture too green. This may be more likely to happen if there's very little white or bright highlights present - but depends a lot on the algorithm the camera uses.

If you've moved the camera around and/or brushed something past the lens then it may take a few seconds for the "white balence" to stabilise.

Other things that are likely to confuse it is if you have an outdoor window somewhere within - or just outside your image; the light from that may be brighter and almost certainly a different colour temperature. Another possibility is that you've got a bright reflection/highlight which is saturating the CCD sensor and confusing the white balance.


You could experiment with using manual white balance "sunny" "cloudy" "tungsten" "fluorescent" etc if you're taking your time taking several pictures under the same lighting conditions. Of course if you forget to set it back to auto, the next time you use the camera somewhere else the colours will be very wrong.
« Last Edit: 07/12/2010 21:18:41 by techmind »
 

Offline Atomic-S

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Why does the camera take green pictures?
« Reply #12 on: 29/01/2011 06:22:25 »
You may be correct; although frankly I do not know if this camera automatically adjusts for white balance or just for overall brightness. It is not the worst camera you can buy, but it is not the best either. It does not have exactly the sort of settings you mentioned, but does have some for "night" and "candlelight" so there must be something like that going on. Maybe at some point I will discover what seems to throw the color off.
 

Offline RD

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Why does the camera take green pictures?
« Reply #13 on: 29/01/2011 11:39:15 »
Anyone know anything about the Olympus FE-170 camera?


http://www.olympusamerica.com/files/oima_cckb/FE-170_X-760_Advanced_Manual_EN.pdf

Unfortunately neither the phrases "colour balance" or "color balance" (USA) occur in the manual.

"fluorescent" does appear (p52) : their suggestion is use flash. 

An "indoor" mode is mentioned.
« Last Edit: 29/01/2011 11:48:54 by RD »
 

Offline Atomic-S

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Why does the camera take green pictures?
« Reply #14 on: 02/02/2011 05:03:16 »
Thanks for the reference, although it does not seem to be very informative.
 

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Why does the camera take green pictures?
« Reply #14 on: 02/02/2011 05:03:16 »

 

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