Demystifying Manual Mode in digital SLR cameras

Camera mode dial set to manual mode

Manual mode is that rather simple roadblock to many beginners in photography. I’ll try to simplify it without unnecessary technical mumbo-jumbo

There are things that control the exposure in cameras, and manual mode lets you control all the three individually. It gives you complete control over the camera’s exposure. You nail the settings right, you’ll get the picture precisely how you want it! But…. If you do not know to set your controls right, the picture will end up looking too bright or too dark or too blurry.

Time needed: 10 minutes.

The three components that manual mode gives us control for

  1. Aperture: 

    The Opening that lets in light. It’s shown by a number. the lower the number, the wider the opening. Wider opening lets in more light. More light makes the photograph brighter.

  2. Shutter Speed: 

    This configures the duration for which the shutter stays open. short duration helps us freeze movement more accurately. Longer duration helps gather more light which is helpful in conditions where light is a limiting factor.

  3. ISO aka Film Speed:

    Controls the sensitivity of the sensor.
    Low ISO – Less sensitivity, cleaner image, used where light is abundant.
    Higher ISO – More sensitivity, more noise, used in darker scenes.

These three components are what we call “Triangle of Exposure”

How do we set each of them? Firstly check if your cameras has a mode dial. You simply turn the dial to set it to the “M” mode. If your camera does not have a mode dial, it can be set through the Mode button or through the menus.

Once, you set the camera into Manual mode, you can use the wheels to change aperture, shutter speed and ISO or you can do it through the menu. These controls are camera dependent.

Bulb mode

Bulb mode

What is bulb mode?

A mode which keeps the shutter open as long as you keep the shutter button pressed. 

Why would you need it?

  1. To go beyond the maximum shutter speed setting allowed on your camera. Most cameras are limited to 30 seconds of exposure time unless you use bulb mode
  2. To control the precise time of opening the shutter and closing it, like while photographing firecrackers and lighting painting. You start the exposure just before the fireworks go off and release the shutter right after it ends. Same with light painting techniques.

Useful tip: Some remote controls allow you to start the bulb mode with a single click of the button and end it with another click on it. 

So, If you see a photo which might need a really long exposure, let’s say, a few minutes, like in those photos with clouds moving in blurry streaks or entire seascape looking like foggy flat surface without any visible waves. You now know how that is clicked.

Example of Photograph captured using bulb mode to make the clouds movement look like streaks in the sky.
Example of a Photograph captured using bulb mode to make the clouds look like blurry streaks. an ND filter was used to control the exposure during the long exposure of almost 5 minutes.

Bulb mode is also used to freeze extremely fast moving objects using flashes. 

In a fully dark room. The shutter is first opened. Then a specialised sound-based or beam based flash trigger is used to fire a flash with a very short burst of light to freeze the movement. The shutter is closed soon after the flash is fired and Viola! you have the picture of a fast moving object frozen in time with the extremely short burst of flash.