You select manual mode on the mode dial top of the camera, right next to the right of the viewfinder. Turn the dial to position (M) for manual mode:
Make sure the pivoting LCD screen is facing outwards (i.e. not towards the camera body) and press the Info button located right next to the viewfinder and just above the LCD screen. This should give you a picture with an M top left, and the shutter speed, aperture and ISO values shown (your picture may be different, but the information content should be the same):
Shutter speed
The command dial is located on the camera top right. The command dial controls the shutter speed – turning the dial increases and decreases the shutter speed. The slowest shutter speed is 30 seconds, after that follows bulb and time mode (will not be addressed here). The fastest shutter speed is 1/4000th second. To avoid camera shake, be careful not to use a shutter speed slower than 1/80th of a second, unless the camera is mounted on a tripod (or you have a very steady hand!).
Aperture
Just in front of the main dial, a smaller button is located:
You can see the graphics is +/- and also a circle illustrating a shutter:
This button, when pressed down, alters the effect of the command dial, so that instead of controlling exposure compensation, it changes the aperture. So hold down the +/- button while turning the main dial, and this changes the aperture. The aperture values are subject to the lens mounted, but typically range from f/1.8 to f/22 or thereabout. The larger the number (the f-stop), the smaller the aperture and the less light is let in by the lens.
ISO (sensor sensitivity)
Finally, to change the ISO setting, find the “Fn” button on the front left of the camera. Pressing this button while turning the command dial changes the ISO value, the same way holding down the +/- button did for aperture:
You can also change the ISO setting using menus: press the information button (i) as shown here, and a menu appears on the LCD screen:
In the top right corner is the ISO value. Use the multi selector (the large round button just below the (i) button) to move the cursor to the top rightmost cell in the screen. It says “iso” with small letters in the bar just above the cell. In the picture above, the ISO is set to 250. Place the cursor over the ISO cell and push the center of the multi selector (ok) and the ISO selection screen appears. Using the multi selector again, the cursor can be moved to the new ISO value, ok pressed and the ISO value is changed.
Auto ISO sensitivity control
There is an option to let the camera (within boundaries) select the ISO value itself, in order to arrive at a properly exposed picture, given the aperture and shutter speed selected by you. It is not a perfect solution in all cases, but it can be a great aid in the beginning especially, in order to avoid over- or under exposed pictures. And it enables you to focus on one thing less in the beginning of your work with shooting in manual mode.
To switch on Auto ISO, press the “menu” button located top left on the back side of the D5600 camera body. Using the command dial (the big round button middle right), scroll down to the so called shooting menu. The shooting menu has a green icon that looks like a camera viewed from the front. Press the right hand side of the command dial to enter the shooting menu, and press the bottom side of the command dial to scroll down to the “ISO sensitivity settings” menu:
Press the center of the command dial (ok) to select the ISO sensitivity settings. In this menu you can switch the Auto ISO sensitivity on and off, set the maximum allowed ISO sensitivity setting (high values gives grainy pictures), set the minimum shutter speed and select the ISO sensitivity.
The minimum ISO value for the Nikon D5600 is 100 – this is a value determined by the nature of the sensor in the camera, and cannot be changed via camera setting.
Notice that when Auto ISO is on, the camera ignores the ISO sensitivity value you have chosen. Only when you switch the Auto ISO off, the ISO setting chosen by you will be used by the camera.
Getting the exposure right
When shooting in manual mode (and Auto ISO is not on), it is very easy to select aperture and shutter speed values that give an over- or underexposed picture. In the bottom of the viewfinder, and also when you press the “info” button, there is a light meter indicating if the picture will be over- or underexposed:
-│ – – │ – – 0 – -│ – – │ +
<————│
If the arrow below the meter points to the left, then the picture will be underexposed. This is the case in the example shown above. If the arrow points to the right the picture will be overexposed, as the picture below illustrates:
Only if there is no arrow visible, the picture will be exposed just right. Minor deviations can be fixed in post, only to some extend for JPG files, more so when shooting in Raw format, but the easiest is to get the exposure right in camera.
Video link
Related reading
Nikon D5600: Still a good buy as an entry level camera in 2021?