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Histogram question.


Well-Known Member
Hi All,
I was wondering what should a "good" histogram reading look like?
Generally speaking should it be a flat line, or more like a bell-shaped curve?


Hi akv,
Try this one to get a basic idea:
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There are some examples included.
As a general rule for the Sigma cameras:expose to the right.
What it means is overexpose slightly,so the peak is somewhat off the centre
to the right side,so you can get more details in the darker parts of your pictures.


Well-Known Member
Thanks Uwe for the helpful link.
I guess everything is fixable to a degree on SPP, but I'd like to try and get good "first shot" results.
I have read on other forums that you should treat digital cameras more like slide film, where you try to expose for the shadows. I guess a little more so for Sigmas since the sensor is layered.
Thanks again!


Well-Known Member

Something that many miss regarding color photographic film, whether negative or positive, is that they too have a Red, Green, and Blue layered architecture.

The Foveon imager architecture has no impact on the sensitivity. Red, the deepest light sensing junction, is just 2um below the surface. The design is based on the quantum interaction of photons and the atoms in the Silicon crystal. Short wavelength photons, in the blue region of the spectrum, have their highest probable interaction just 0.2um into the crystal, where as the long wavelength photons, in the Red region, don't interact until they travel ten times further.

The stacked architecture does not reduce sensitivity across the spectrum and in fact Reds end up being easily saturated even though they are sensed at the deepest level.

I've done my home work and prior to my SD14 purchase, I searched out and read the patents that were issued to Foveon for their technology. If you're up for a techi read, here's one of them:

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Well-Known Member
Thanks Steaphany,
From my short time on here I've come to admire your wealth of esoteric knowledge! Well esoteric to me. lol.
Thanks for the knowledge! It's so exciting to use something like the Foveon sensor that has so much potential for the future and still has amazing results today.