How camera Shutter Works?

Our Camera is made up of two curtains. They are names as First Curtain (upper) and Second Curtain(lower).  These curtains are always closed. Unless the curtains in out houses, camera curtains move vertically. When you press the 'shutter release' it tells the camera to open the shutter. Then the first curtain opens to reveal the light to the camera sensor. Then the second curtain follow behind to hide the light. Then the first curtain reset ans wait for you to release the shutter release again. In slower shutter speeds like 1/200 and below, only the second curtain will wait for the first curtain to open completely.

Sync Speed: 
Sync speed is the faster shutter speed, of a camera that allows the first curtain to fully open before the second curtain begins to follow. In another words it is  the fastest shutter speed you can use with the studio settings.

Consider if you want to click a photo on studio in which the model is jumping. In this case you should use a faster shutter speed in normal case. But if you use a shutter speed faster that sync speed, there will be a black line in the resulting photo. What you can do on this situation?

EXPOSURE TRIANGLE

Exposure Triangle is made up of three things:

1. Aperture
2. Shutter Speed
3. ISO

Let us have a look how light enters a camera and makes a picture.

The light coming to the lens has to pass through something called Aperture and then passes through the Shutter and finally hits the Sensor.

Aperture: It controls the quantity of light should come to the shutter and then the sensor.
Shutter: It controls the duration of the light.

Aperture and Shutter Speed and very much related to each other. Let us looks how can we balance their values while taking a picture.
If we have a large Aperture opening,more light coming to the lens,  we can go for a fast shutter speed (1/2000). Same case reverses if we  are using a small Aperture(Shutter speed 1/15).

To help us regarding this matter, most of the cameras having Shutter Priority Mode and Aperture Priority Mode.  If we go for a Shutter Priority Mode, the camera will recognize the shutter speed that set by us and provides the best Aperture for the best result.   In Aperture Priority Mode, device will choose the best Shutter speed for a given Aperture for the bast result. In Nikon Cameras, Shutter Priority Mode is given as 'S', where as in Canon it is gives as Tv(Time value). Aperture Priority Mode is given as 'A' in Nikon and 'Av' in Canon cameras.

ISO:  In a low light situation, our eyes readjusts its the sensitivity to light accordingly. Same way, while shooting in low light situations, we can adjust the sensitivity of sensor of the camera. If we are shooting on a bright sunny day, we can go for low ISO values like 100 or 200. But at night or dark situation, we have to use ISO values like 1600 or 3200.  

PANNING - Technique for taking action photos

This technique  uses a slower shutter speed. Camera and the subject will be in motion, not the background.

Example for Panning Shot:

To get a great Panning Picture:
1. Shutter Priority Mode
2. Shutter need to be slower as possible (1/30 or 1/15)
3. Continuous auto focus mode (AI SERVO  mode in Canon Cameras)
4. Center Auto focus Point
5. Shoot when the subject in directly in-front of you.
6. Continuous Drive Mode (you get a bunch of shots in a single shutter release)

APERTURE VALUE - Definition

Aperture value is the size of the hole the light passes through.

Small Opening - Large Aperture Value
Large Opening - Small Aperture Value

Aperture is found in your camera's lens, not in the camera!

Lens Specification:
85mm 1:1.2 :  Here Milli meter  is the focal length and 1.2 is the widest aperture value of the lens. '1:' means 'in a minute'. The Folca Length always comes first followed by the Aperture Value.
70-200mm 2.8:  If the focal length is a range, it means that the lens is a zoom lens. It zooms from 70mm to 200mm.
70-300mm 4.5-5.6: Obviously its a zoom lens which zooms from 70 mm to 300mm.  Now comes '4.5 - 5.6'. This means the aperture will not be stay constant while zooming. It varies. Most of the consumer lenses are of this category as lenses which give constant aperture value, costs more.

WHITE BALANCE

To solve issues with color.

The light source may be warmer or cooler. Adjust the white balance first and then take a picture.

DEPTH OF FIELD

Shallow depth of field. : It means subject is in focus and background is out of focus. 

There are THREE things that control DEPTH OF FILED. 

1. Aperture 
2. Focal Length
3. Distance from Subject.

1. Aperture: To get a shallow depth of field, you need a wide (large) aperture opening (a small aperture value). The larger the opening, the shallower the depth of filed.  

2. Focal Length: Focal length also have a great impact on depth of field. When focal length increases,  the depth of field decreases. 

3. Distance from the subject:  The closer you are to your subject, the shallower your depth of field will be.