What is the right exposure in Photography?
Scientifically, correct exposure is when you record the original scene in such a way that it is as close as possible in its tonality to how it exists in reality. The camera does not see in the same manner. When we see, our Brain interprets a lot of information and we see less contrast than there actually is. We do not see everything together but kind of scan the area and the pupil of our eyes continues to change its size as per the subject.
But then when you shoot, you express the scene through the camera as a medium. It may be different and not the same. It's purely your vision of the scene and it does not always have to be truthful. If you are documenting something the exact tonalities of the original scene may play an important role but otherwise, it's the impact that you make with your photograph which matters more.
Most people know when an exposure is right or wrong. Overexposed photographs are overly light, and detail is lost in the highlights and the underexposed ones are completely dark.
The Right Exposure
Right exposure is whatever makes your subject look its best in the type of photograph you create. That means exposure is definitely subjective. What may be correct exposure for one photographer may not essentially be the right exposure for another photographer in the artistic terms.
You as a photographer have to decide what is the correct exposure for you and for which area of the photograph. Contrary to how our eye sees, you cant get everything correct unless you are using other means like adding a Flash, Adding a reflector or using HDR modes on your camera. For travel photography you need to choose between what is relevant and what is not. It is understood what is visible outside the window even though it is overexposed. Interestingly, the light entering through the window is reflected from the walls around and creating a deep warm tone, which is adding to the overall mood here.
High and Low key
Underexposed photos are overly dark, and detail is lost in the shadows.
But still you can create images which are either inherently Dark or Light because the elements themselves are too dark or too light or your illumination was such that you want them to look so. A bride in a white wedding gown against a bright window or a white wall is light and bright to begin with. This is not overexposure as such but the inherent quality of the images also known as a High Key Image.
On the other hand a dark skinned person in a black jacket standing against dark wall will make a Low key photograph. Adding more light will not help as that will not retain the original tonality of the scene. Similarly we do not have to reduce the light from a High key Image as that will remove the very character of the photograph being High key.
High Dynamic range
Unfortunately, the world typically offers up a range of tones greater than what is possible to capture with a sensor. First, you might not be able to hold detail throughout the image with your exposure. Most digital photos look their worst with any overexposure or very dark underexposure. Good exposure results from the appropriate combination of shutter speed, aperture, and ISO speed.
The Interior of the Indian Parliament required every detail to be visible. With the help of additional external light, the inherent contrast in the hall was reduced. The additional lights help fill in the dark areas and the difference in the tones is reduced. At the time of Film, Neutral Graduated filters were commonly used to bring the balance between the very bright and dark areas in a photograph. Now, in the Digital era, one can take multiple exposures specific to particular tones and then blend them together in Adobe Photoshop.
Retain the Detail
The important thing about exposure is that important detail, dark or light, is captured properly so that the scene is light or dark in accordance to the subject, the way it exists.
Even though the light is coming from the evening sun on the right, it is uniformly covering the whole scene visible in the frame and there are very less areas which are on the extremes of the exposure latitude. If the contrast is increased on the camera beyond a point, we will start losing detail on the extremes.
Not Always necessary
Europe | f/5.6 | 1/60 | 65mm | Canon EOS 5D mark III
Not having the detail inside the bus has rendered the person in the bus as a silhouette and all this is allowing the attention to be on the couple outside the window. Red is a strong colour and stands out even if present in a very less area.The darker interior has formed a Frame around the scene outside. If everything was clearly visible, which actually is to the human eye, the impact would not have been the same.
Interpretation of Exposure
Exposure can be determined solely by the camera, interpreted by you (as the photographer) and the camera together, or solely by you. All cameras have an inbuilt Photometer inside the camera to measure how much light is entering the lens to expose the sensor. In most of the situations the modern metering systems will give you the correct settings and even set these settings on certain modes for you. Based on your own experience, you can alter this suggested exposure to make the photograph dark or light, the way you want it to appear.
Yes, It's not always important to have a very realistic view of the scene you are photographing. It may appear better if it's darker or lighter than as it exists.
The exposure in this closeup of the young girl in Nagaland is based around her skin tones and the background has been rendered dark. It was relatively dark but not so dark for the naked eye. The camera sees differently. And when we show how the camera sees makes things more interesting for the human eye.
The Photograph of this devotee in Allahabad, Sangam has been shot against the morning rising sun in the River, Ganges. The camera's metering will suggest the exposure that is correct for the brighter areas and thats what has been set on the camera. The camera does not know that the person and the boat exists in the scene. If I was shooting a model or a known person, I may have employed a different methodology to create the same photograph. I may have added artificial light of a flash or something in such a manner so that it continues to remain natural but get the detail in the person so that it is clear from the photograph that a specific person is performing prayers, while right now its a general photograph showing one of the several devotees performing a prayer.
Another one with water shot in Phuket, Thailand. Although the background is quite bright, since the sun is not absolutely against the camera, the subject has not been rendered as a silhouette. Rather the colours are quite deep and saturated.
Flash has been used from a direction closer to the camera. It has illuminated the flowers and the mother as well.
The flash is away and creating a short lighting on the Bride. Short lighting is when the side of the face away from the camera is illuminated as compared to the one towards the camera. This set up is emphasising more on the bride as compared to the flowers and the mother.
The difference here is that there is more of an eye contact between the Bride and the Mother. One can still make out that there is the mother on this this side even though she is almost in complete darkness.
So, Exposure is all about what you want to show and how much you want to show in a photograph. This completely changes, how an image appears to the viewer and what kind of a visual impact does it create.
You should know what to sacrifice
The porch area in the passage is obviously dark as there is less light reaching here, in terms of the way the camera evaluates the scene. Having more detail in this area would have sacrificed the blue of the sky and the white of the Buildings. The "tunnel" are being dark helps in bringing our attention to the scene ahead. A little bit of the detail in the motorbike further directs the eye to the outside. We like darker blocked areas in a photograph as compared to white washed out areas.
The exposure is based on the overall tonality of the scene and the lamps have been sacrificed. Getting detail on the lamps was not so relevant and it would have rendered rest of everything in darkness without getting the fine texture and details of the buildings and the bricked road. The two figures are almost in silhouette which is working here.
f4 | 1/30 canon EOS 5D mark III Aperture Priority I Evaluative metering |. ISO 3200 | White Balance -Daylight