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Old Dec 11, 2005, 2:47 AM   #1
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The Following problem exists especially while using the Flash Indoors:
The results suffers from something like a "gray layer" on it.
It doesn't matter if you change the camera settings (e.g. W/B, Exposure, Metering, etc), and remember -we're dealing witha flash-indoor photo.
This layer can be removed by using any kind of Auto Contrast tool, no matter which software you're using.
Attached here is an example for this problem. In the following reply you can see the same photo, after using auto contrast.
Does anyone here familiar with this problem through your FZ30?
Can it be cured ?
Thanks,
Ju
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Old Dec 11, 2005, 2:48 AM   #2
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Here is the same photo, after using an Auto Contrast tool:
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Old Dec 11, 2005, 3:04 AM   #3
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I think it is an exposure thang. The way the camera's (light) meter works is that it sees a situation and takes the average (white + black) to get middle grey (18% reflectance). What this means is that if you shoot a picture of a white wall, the camera will average it to middle grey and you will get a middle grey wall. If you shoot a black wall, it will expose for middle grey and get a middle grey wall again. Obviously, you want your whites to be white and your blacks to be black. You took a picture of primarily a white source, so what did the camera do, expose it down to a grey wall. Try taking the picture again, this time add more light into the camera. You can open the aperture, or do a bracketing thing. What used to be true in film photography is even more true in digital photography. You want to get the properly exposed negative. Your digital "negative" is underexposed. Granted, in digital photography it is better to underexpose than overexpose (this is also true of slide film). What you did was increase contrast which turned your light grey wall lighter, so it looked like it fixed your problem. But I believe if you tried to print your picture it would look too contrasty. Try taking the picture againthis time letting more light into the camera. Also, try googling "The Zone System" and it will explain how to expose correctly. It is a bit more complicated when you are using a flash but when you understand the principles it is easy to compensate (basically adding more light when you shoot something white, and darkening when you are shooting a primarily black subject). Hope this helps. And FYI the contrast on the FZ30 is normal.
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Old Dec 11, 2005, 3:12 AM   #4
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I don't really see that as a problem. You photographed a low contrast scene and the camera reproduced it as accurately as it was able to. If your original photo looked like the one with the increased contrast, then there'd be a problem.

You want your camera to pick up as high of a dynamic range as possible. This means that you want detail in the dark areas, and detail in the light areas. The higher your contrast is, the more detail that will be lost in those areas. For example, if there was a window in the background and the sun was out, the first picture would show a lot more detail of what's outside, where an image with the contrast of the second would turn it all white. And as you've demonstrated, you can increase contrast afterwards. You cannot, however, recover detail that has gone completely black or completely white.
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Old Dec 11, 2005, 5:35 AM   #5
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Wow Nancy! Your seances with Einstein are really paying off! (or is it Ansel Adams?) Just pulling your chain...that was a pretty neat explanation. (figurative pat on the back)

Kd
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Old Dec 11, 2005, 7:07 AM   #6
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Hi Nancy,
I got the Black-Gray-White tangled 'relationships' - Thanks a lot.
Later on I'll implement your professional advice and present the results here.
But, I'm afraidthat we're dealing with something else here:
The phenomenon I described appears almost in any lighting /scenery conditions.
For example, please take a look at the following photo, in which I didn't even use the flash. It was takenat sunset time, lights were already quite dim.
No "pure" white or black background to disturb.
See the difference between that and the same one, only after a slightly Auto Contrast correction (attached as a reply for this message).
So, I wonder whether my FZ30 alone has something wrong with it's CCD or is it that the Default ContrastSettings (both "standard" and "high"), in all FZ30 family,is maybe "Normal", as you mentioned,but surelynot as good as the default contrast settings of some other digital cameras from the same level (or even below it).

Anyway and most important, Thanks a lot for your advice and for the time youdevoted for that, really appreciate it, Thanks.
Ju
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Old Dec 11, 2005, 7:33 AM   #7
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Here is the same photo, after an Auto Contrast correction.
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Old Dec 11, 2005, 7:47 AM   #8
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My canon spreads the contrast automatically.
The FZ5 comes closer to reality in doing just what I intended to shoot.
I don't need shots in foggy wheather which look like full sunshine.
This contrast correction can be done lateron, but I guess the reality was closer to your first cat picture?

Sven
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Old Dec 11, 2005, 8:31 AM   #9
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I agree with Nancy that is an exposure thing but if you feel its contrast why not raise the contrast settingin the camera?

I feel you would get more like what you apearantly want by changing the exposure compensation to minus 1/3 or 2/3. Also you could experiment with how you meter differant modes and / or spots.

Here is the cat with the exposure adjusted nothing else. I would also sharpen it a bit but did not want to fool with your photo.
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Old Dec 11, 2005, 3:45 PM   #10
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Shooting with higher contrast reduces your dynamic range. I usually shoot with minimum sharpening and contrast so I have the most dynamic range and fewest artifacts to work with. I have a Photoshop action that applies PT Lens, defogging, a little sharpeningand auto contrast to an entire file. I also save the originals though for anything I want to work with. My older version of PT Lens doesn't have the FZ30 in the database, so I just defogged and used auto-contrast.There is alsoa little Shadow/Highlight to try to compensate for the uneven flash exposure. And I was afraid the candle was going to fall off the leaning speaker.
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