What is white balance in camera?

Red, Green, and Blue are the 3 primary colors that form the white light. They are mixed in various proportions – depending upon the color temperature of the light. If the color temperature is high – the light is bluish. If it’s low – the light is reddish.

 

Definition of White Balance
The white balance is used to remove the unnecessary color casts so as to make the image look more natural. Hence, it  is set according to the color temperature of the light sources.
Working with White Balance
In most of the cases,  a white balance is used to avoid the casts. While some photographers choose to use  the “wrong white balance” to produce very creative pictures. You can also create very warm pictures if you use the “shade mode” in the daytime. The opposite (cold) is valid if one is using “tungsten mode”. While DSLR has special mods for all the different types of lights – it’s not really necessary that you must use flash white balance when you use the Speedlight or strobe. Most of the modern digital cameras will calculate ambient light and provide you with a decent result on an “Auto White Balance Mode”, specifically when two or more color temperatures from the different light sources are mixed in the one set. In such cases “Auto white balance” is good to use, or neutralize particular light sources with color filters or gels. There is also the more professional way to set up the white balance by using neutral white, it called “Custom White Balance”. Most of the DSLRs will have instructions on how to set up the “Custom White Balance” for your particular camera.
What is white balance in camera?
While shooting on film was required to adjust light sources with filters and gels. However, when we are shooting with the digital camera, it’s easier as you can use the Auto White Balance (AWB). Also, if you photograph using RAW or DNG format, you may adjust your white balance later while processing the images. However, some of the details may be lost if the transformation is too dramatic. So it is always recommended to use the correct white balance during the shooting. To adjust the white balance in RAW pictures, the photographers use “Gray cards“. They are put within the set later as they help in picking the neutral gray during postprocessing.

 

P. S White balance in food photography is usually aiming the daylight color temperature (except for some special occasions like candle light dinner or so). That’s why many food photographers say that natural light makes food look tastier.

What Is Aperture in camera?


The aperture definition in digital photography

 

The aperture is the unit of measurement that defines the size of the opening in the lens. The size of this hole will regulate the image sensor’s degree of exposure to the light.
It measures in F-stops. The diaphragm is the device which controls the aperture opening. So we can say that the aperture is the hole which control the light entering trough the lens to the image sensor.

 

Get the DOF
The aperture controls depth of field (DOF) the smaller F-stop number the more blurred background you will get and opposite, a background will look sharp with the large F-stop number. When people talk about small F-stop numbers it called “big aperture” and when its large F-stop number it called “small aperture”. Even though it sounds confusing that just refers to the size of the opening when the aperture is wide open and more light gets in it shown with small numbers such as F/1.8 it called “big aperture”. “Small aperture” (F/14 or F/22) refers to the small hole and lesser light entering in.
What Is Aperture in camera?
Moving objects and aperture
While “small aperture” provides more sharpness it also requires more time to perform. Which also guide us to the conclusion that when we deal with the moving objects we may like to use “big aperture” unless we want some blur motion effect. But what if you want to photograph people in the restaurant and it doesn’t have big windows and light is dim, but you still need a sharp picture? You will make an adjustment to the other components in exposure triangle, read here how.

 

Buying the lens

Every lens has its own aperture ratio. The smaller number on the lens (F/1.2 or F/2) the better it behaves in a low light situations. However, if you only shoot with studio lights you may be fine with the larger numbers on your lenses such as F/5. As we talking about food photography here where the nice bokeh is an advantage, you may like to purchase lenses with bigger aperture diameter (F/1.2 or F/2). And for sure read some reviews before buying.

 What Is Aperture in camera?
P.S. If you like to click stories about street food, markets, malls and other activity you may need to use faster shutter speed in a low light condition. In this situation, you will need to adjust shutter speed aperture and ISO read here how.

What is color temperature in photography?

The color temperature one of the most important things in photography. I would say it also part of photography multiplication table, something all photographers know and use all the time.

Definition of the color temperature
Well, technically speaking color temperature is one of the many characteristics of the visible light. Each light source has it own color temperature.  Take a look at this table:
Temperature Source
1,700 K Match flame, low-pressure sodium lamps (LPS/SOX)
1,850 K Candle flame, sunset/sunrise
2,700–3,300 K Incandescent lamps
3,000 K Soft (or Warm) White compact fluorescent lamps
3,200 K Studio lamps, photofloods, etc.
3,350 K Studio “CP” light
4,100–4,150 K Moonlight
5,000 K Horizon daylight
5,000 K Tubular fluorescent lamps orcool white/daylight compact fluorescent lamps (CFL)
5,500–6,000 K Vertical daylight, electronic flash
6,200 K Xenon short-arc lamp
6,500 K Daylight, overcast
6,500–10,500 K LCD or CRT screen
15,000–27,000 K Clear blue poleward sky

The color temperature measured in Kelvin (K). As it visible from the current table the light temperature varies from reddish to bluish tints. Natural daylight is usually between 5500 to 6000 K but in the “magic hours” it became as warm as 2000K as well. Light below 5000 K (1,700 – 5000K) considered as warm colors and the light above  daylight (5000-27000K) referred to cool colors.

Color temperature and White Balance

In photography, the color temperature is always used along with term “white balance”. To create correct white balance photographer need to understand with what color temperature he deal with and adjust camera settings accordingly.

Find more about White Balance Here

Learn Photography Light. Part #1

In the first lesson, we will try to understand the light nature through an experiment. The direction of light is one of the fundamental ideas of photography. Some of them are the amount, angle, temperature, and softness of light. But they will be touched in the future lessons. Today it’s all about the direction.

You will need:

  • The object — let it be a cup of tea, a slice of fruit, an egg or the single colour ball (ideally white). Use all objects one by one for a better result.
  • Table lamp, white bulb is recommended
  • Table big enough to place the lamp at a 30- 50 cm distance from the object
  • White paper to cover the table (if table is white, it’s not necessary)
  •  Camera (smartphone will do)
  • Tripod is ideal but not necessary
  • Stool and big window in the daytime for the second experiment

Note: Use an Auto White balance in both the cases.

 

Learn-Food-Photography-Light2

Experiment No #1. Artificial Light

Place the object on the table. Let’s call it “stage”. Imagine that your object is located in the center of an analog watch, and your position to the object is 6 o’clock. Put the camera on a tripod, (alternatively, you may keep it in hands at the same position during the experiment). The angle of your camera is supposed to be 45 degrees to the object. Place the lamp on the left front side (approximately 50-30 cm from the object) in a “7 o’clock” position. Then switch the lamp on. Capture the image. Shift camera to “8 o’clock”, again capture the image. Shift lamp to “9 o’clock” and do it again. Keep repeating till your lamp appears at “5 o’clock”. Try to make one image with the lamp at “6 o’clock”, it will give you an idea that why the use of an inbuilt flash is never recommended by professional food photographers!
When you will see all your images, analyse the position of the shadows and how light covers the object, and how much shadow remain with every position of the lamp. The light will work with your object in almost a similar fashion most of the time. This lesson is very important because all other information will be somehow related to it.

Learn-Food-Photography-Light1

Experiment No #2. Natural Light

Put the stool covered with a white paper about 1.5 meters away from the window. Place your object (preferably the white or single colour ball in this case) on the stool. Position your camera at an angle of 45 degrees from the object. Stand near the stool in such way that the light from the window falls on the left. Consider you are standing at “6 o’clock” position. And as your light source is not movable, you will move along with the camera. Step to “7 o’clock” and click the picture, then to “8 o’clock” and click again. (Try not to block the light when you shoot from “8, 9, 10 o’clock”). Once you clicked all the 12 pictures, see all of them together.

Learn-Food-Photography-Light3

 

When you will compare all the 24 pictures, you will find the difference between an artificial and a natural light. The details the light temperature, and the softness of the light will be all different. Remember these values are like photography multiplication table for number 2. We will discuss other qualities of the light in the upcoming lessons.

P. S. Hope these experiments gave you some food for thought. Share your experience with fellow readers in comments. Cheers:)

What does ISO in a camera

What is ISO? Sometimes it refers to the International Standard Organisation. But in photography, it’s an important setting related to the sensitivity of the film or sensor of your camera.

Definition of ISO

In the analog or film photography, ISO indicates the sensitivity of the film. The lesser sensitivity, the lesser is the noise. This way you could probably use 800 ISO film for the night shoot. For the bright day, something like 50 ISO is apt. When I was shooting, the most versatile was 200 ISO as it was possible to use it for the various light conditions.
In the digital cameras, it works in a similar way but it also indicates the sensitivity of the image sensor. And if you like to achieve the noiseless image for commercial usage, you may like to use ISO – 100.

How ISO works?
ISO is not the only setting which you can change to click the image in a poor light condition. It usually works along with the Settings of Shutter Speed and Aperture. The excessive noise created by the large ISO numbers sometimes can be reduced during post processing. But as a result, the image loses its sharpness. Concerning the fact that the image may lose its quality, it’s better to use other settings to create conditions for a better ISO numbers. However, if the light conditions during the focusing were not perfect, you may get an extra noise even with ISO 100. Surprisingly in this situation, you may need to change ISO for the higher number like 200.

What does ISO in a camera


It also important if your subject moves or you are shooting handheld. In such a situation, ISO is usually increased to get a sharp picture. Higher ISO numbers such as 600 or even 1600 (depends on the quality of your camera) are often used for street photography. However, basic DSLRs have smaller sensors so the amount of noise on 600 ISO may destroy the picture.
What does ISO in a cameraConclusion
To decide what ISO range to be used, ask yourself the following questions:

  • Is that enough of light?
  • Do you like to have visible noise in your picture?
  • Are you using the tripod or handheld?
  • Is your subject static or moving?

P.S To find more about the Exposure Triangle – read about Aperture and Shutter speed.