I'm new in photography, however I have some basic knowledge of exposure, aperture, etc.
I own a Nikon D7000. The issue I've found in number of pics I've taken (in P mode) is that whenever the scene is relatively dark and there is a bright contrasting lighting source (bulb or sky), then I get too dark of a picture overall. Here is one example.
What I can do to make light source be darker and the rest of dark scene be brighter?
You're asking the right question, "How do I properly expose...?" Put the emphasis on the "I" part of that. If you are using "P" mode then you are not determining the exposure. Your camera is. And your camera thinks it is taking a snapshot of your Aunt Mathilda at Christmas, and has no idea that you are trying to do something creative. So in cases like this you need to take control, meaning switching to "M" manual mode, or at the very least, playing with camera features like "exposure compensation" or "exposure lock" or "spot metering". Look these up in your camera's manual.
Generally, you want to look at a scene like this and decide what parts of it you want to be be the well-exposed. Presumably in this photo you wanted the worker to be be a little brighter, so you could see more detail. These could be done a few ways:
Dim the light.
Barring that, pretty much nothing without some serious lighting equipment that light up such an extensive the foreground to reduce the difference.
What you are encountering is a situation where the scene has a greater dynamic range than your camera can capture. According to the metering-mode in use, the D7000 correctly chose not to over-expose the highlight and that made the rest of the scene darker.
If you apply positive EC, everything gets brighter so the light source will start blooming. In that scene, I am guessing you can go +1 EV and you should see an improvement in the foreground while the light will probably not bloom too much.
You can get the same effect as applying EC by going into Manual mode but that does not change the relationship between the bright light and the dark areas.
Meter what you can't control. I'll use an example of an office interior balanced with an exterior sky:
How the balance was achieved was metering the exterior (I used a Sekonic meter, but you can use your camera just as well). I got f/8 at 1/250. Fine. So then I set up a single bare bulb behind the camera and a small diffuser to mitigate the glare and took readings inside the office until I got the exact same reading.
Now, the image you showed is challenging because there is a great deal of area and several relatively small blown-out light sources. You may not want to bring artificial light to the areas of interest as I did here, but that's one solution. Another is HDR, although there you concede a lot of control to computer algorithms and you don't know how well you did until you've post-processed. Yet another way is to do two exposures: One for the areas of interest (spot metering in camera or with an external meter is really handy for this), and the other for the light sources you don't want blown out. Then composite them in post.
In any event, your camera is good for between 3 and 5 stops of dynamic range. What you've shown is greater than that, so no matter how you meter it, you can't get one single "right exposure" with just ambient light.
You have quite a few options. The easiest would probably be to simply increase your EV value. EV stands for exposure value, and will allow you to quickly make the scene brighter or darker as you wish. On your Nikon D7000, the button is denoted by a +/- symbol and it is located right next to the shutter release button and on/off button on the top of the camera. Just select that button, and use your scroll wheel to increase the brightness(+1,+2,+3) or decrease the brightness(-1,-2,-3). Technically this is called increasing or decreasing the exposure.
If you have a scene that has a very bright light source(the sun) as well as dark shadows, this might beyond the capabilities of your camera sensor to capture it with a single exposure. This is where HDR photography can come in handy. It allows you to capture a scene at multiple different exposure values, and combine it into one image.
A third option would be to change the metering mode that you are using. If you are in P mode I am guessing that is set to automatic or some type of evaluative metering of the entire scene. You can test out spot metering, where you are only evaluating a small portion of the scene for the correct exposure. I am not sure if the D7000 allows you to do this in P mode or not, but take a look at the manual and see where it talks about metering modes, and that should give you a good place to start.
In response to this comment "I get too dark of a picture overall":
After reviewing the image, I think your main issue here is the metering mode. Try switching that up to see how your results differ. You could easily setup a scene like this in your own house to test the differences.
In response to this comment "What I can do to make light source be darker and the rest of dark scene be brighter?":
As others have stated, this is beyond the capabilities of your camera sensor. Your camera simply cannot expose the very bright bulb and the foreground at the same time. HDR is your friend in this case.
make light source be darker and the rest of dark scene be brighter
You can't. You cannot adjust the contrast difference between the light source and the scene. Even if you dim the light source, you will be dimming the scene proportionally, if the light source is the major illuminant.
If the scene is lit by a combination of light sources (e.g. ambient window light and a lamp) then you can change the ratio of these sources by modifying one of them (usually the lamp), by either turning it up (not likely) or adding a ND filter in front of it to reduce its contribution. However, looking at your scene it does not look like you have control of any of the light sources (windows or billboard flood).
You are therefore left with manipulating the image in post. You can take two frames, one exposing for correct exposure of the background (e.g. ceiling) and a second image at -2 EV or so, to capture highlights in the light sources and reduce speculars. You would then combine these two by masking.
I personally would not worry too much about the lights, unless you are taking a photo which must have a high dynamic range captured. The lights are not the focus of the photograph, it's the billboard and the person, and that's what you want to expose for.
I shoot manual most of the time, but I would have exposed this particular photograph maybe a stop brighter (rough guess). If you're shooting in a semi-automatic mode like aperture priority, this means you need to dial up your exposure compensation.
Take this photograph I took recently as a good example of high dynamic range and the choice of what to expose for. I always choose to expose to bring your eyes to the people in the scene, whether they're facing the camera or looking away from it.
For me, it's all about the people and in this image. While it's not ideal that there's a bright light behind the guitarist, it really doesn't make too much difference to me. The fact is that the light source itself is far brighter than the current exposure would allow and to expose for the lights would likely mean everything else was black or close.
The solution is simple. You take 2 pictures, one you expose for the bright part (dark part is going to be very dark), the other you expose for the darker part (bright part is going to too bright), then you combine them in Photoshop.
Some people are interested in more than people and would like to see the whole scene without losing composition.
From what i have read, it seems the camera is just not good enough. In certain composition where theer is a vast contrast in light and darkness, you will have to use artificial light to match the scene as close to the eye sees it.
