From a discussion I was having with Paul, I played around a little with high contrast scenes. He has some images where the straight out of camera jpeg has not brought up the detail in a dark area (eg a dark statue) against a strong back lit background.
On Nikon dSLRs, a setting called 'active D lighting' became available for application in shooting (as opposed to post processing, whether in camera or on downloaded files).
So, I was taking some shots of the fowls with the D40x - it doesn't have ADL option for shooting but it can be applied in camera after the shot. A couple are below, and it shows how powerful this (software) application is, and also illustrates the problems that any photographic medium has in capturing a whole scene the way our eyes see it, or more accurately as our brains post-process the incoming light to 'pull up' shadow detail.
So, below a couple of comparison shots - / + ADL. I suspect that in Paul's Lumix FZ1000 there is a setting analagous to ADL, probably with different levels of application. [He might have to resort to reading the manual >:-o).
OK, the examples
but
The photo medium can only capture the light that is there. If you take the film medium, the sensitivity to light is uniform across the film negative - and adjusting exposure will affect the whole area uniformly. That is, a whole exposure adjustment can only be applied uniformly to the whole exposure - if the qualitative and quantitative difference in amount of light between to parts of a scene is too great, the physics per se doesn't allow for getting both parts perfectly exposed for detail.
But our brains do this all the time - segements of our field of view get post-processed to enable us to see both the full lit and the shadow with acuity. Computers can, thanks to clever programmers like Python, detect the contrast areas and locally adjust the exposure. In the old film days, you could do this in the dark room with simple physical tricks such as waving a piece of paper over an overexposed area as the negative was being processed ie between the light coming through the negative and the photographic paper being exposed to get the print.
Another way of getting at this is where you 'tell' the camera to 'meter' the light to inform the exposure it will apply - shutter speed, aperture (and with digital, ISO). The standard default is 'matrix' or 'averaged' metering - the light meter / software tries to balance all of the incoming light. Then there is 'centre weighted' - the light meter / software takes more account of the area where the light level is read (typically the focus point - I guess face recognition will have some priority - my dSLRs don't have it or I don't turn it on). Then there is 'spot' metering - the light meter / software meters just on the small focus area. Spot allows a small subject to be exposed 'correctly' even if the surrounding scene is very dark or very bright. But, as above, the metering is a physical adjustment affecting the amount of light hitting the sensor or film, not a software interpretation of the incoming light.
Yet another way is 'exposure compensation' - often has a dedicated button with a +/- decal on it - you can dial in how many 'stops' (more precisely electron volts, EV) more or less than the camera's meter thinks the 'correct' exposure is - how much light gets let in. Generally goes in 1/3 EV steps - eg +0.3, +0.7 etc.
On my cameras, choosing metering area and exposure compensation are NOT available in the AUTO modes - needs to be in Manual (I rarely use, except for moon shots), Aperture priority (I use most - set the 'f stop' - how wide open is the lens, how much light gets let in, also affects depth of field), Shutter priority (how long the shutter is open, I use when I want to ensure a fast shutter to freeze motion and/or avoid effects of camera shake), Program mode (I don't use this much but its a bit like A and S).
And having mentioned moon shots, this is a classic example of needing to balance a really bright object in a really dark background - if you don't meter on the moon you generally just get a 'white out'.
So, the moral of this story is:
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