Basic Camera Terms Explained VERY SIMPLY – Aperture, ISO, HDR, Saturation
Exposure compensation, Dynamic range, Focal length, Aperture, ISO, Shutter speed, Focus, Saturation, Bokeh, Aspect ratio, Optical Image Stabilization (OIS), High Dynamic Range (HDR) just way too many terms.
So, I try to explain all basic terms related to camera and photography in general. I promise I won’t go too technical here everything will be put across in simple terms as the title suggests.[lwptoc]
What is the camera?
let’s begin with the most basic most popular term camera. Now when you say camera, it’s usually a combination of two things sensor and lens.
It’s not just with DSLR or any professional camera, even a smartphone camera has a sensor and lens.
The difference is, on a DSLR you can change lenses for more versatility but on smartphones, the lenses are fixed.
That’s why these days we are seeing multiple cameras on phones so that lenses with different capabilities are all available to use on the same device.
What is Exposure?
Now the amount of light that goes through the lens and hits the sensor it’s called exposure. It’s the little meaning how much a sensor is exposed to light.
This exposure is decided by a combination of three things
- Shutter Speed
What is Shutter Speed?
Shutter speed is the amount of time a sensor is exposed to light
For Example, if you set the shutter speed to one-tenth of a second then the shutter opens for one-tenth of a second and then closes.
So, for the moment let’s forget about aperture and ISO, let’s keep them constant and just change the shutter speed and see what kind of difference it makes.
the shutter speed of this image is one-thousandth of a second.
this one five-hundredth of a second
this one-hundredth of a second
this one-twentieth of a second
So, in broad daylight, even one-twentieth of a second is too much time
What is Aperture?
Aperture decides the amount of light that enters the lens in a given amount of time.
Do you see these blades [In the Image] moving inside the lens, so when they close down the gap at the centre is so small, so the amount of light entering the lens is very less.
But as we increase their aperture the blades open up and the amount of light going in increases as well.
Once again on DSLRs and mirrorless cameras, you can change the aperture.
So, larger the number narrower the aperture. But on smartphones, the aperture of the lens is generally fixed.
The exceptions are Galaxy S9 & S9 plus, Galaxy s10 & S10 Plus, Galaxy Note 9 & Note 10 and OPPO phone the r17 Pro. The 2 – aperture values available are F 1.5 and F 2.4
What is ISO?
It’s the sensitivity of the sensor.
As you increase the ISO more amount of light is captured by the sensor. But increasing ISO also introduces a lot of noise.
Here’s the comparison of images shot at ISO 125 and ISO 3200. The images are equally bright because for the left-hand side image I set the shutter speed to ¼ of a second while for the other image it’s one-sixtieth of a second.
So, if you can adjust the shutter speed and aperture to bring in lighter, why do we even need ISO?
The reason is we can only adjust the other parameters to a certain extent there are some limitations.
let me explain, we shot 99% of the image handheld, without any additional equipment like a tripod or anything and our hands tend to shake a bit. They cannot stay stable even for one second. There will be a still shake and it will reflect in the final image.
Here are a few pictures shot at one-second shutter speed.
Every single picture has a bit of blur due to camera shake it’s inevitable. Usually, the maximum shutter speed for a blur-free image is around one-tenth of a second for a typical smartphone.
If the lighting is good.one-tenth of a second is more than enough it’s too long.
But under low light, it’s usually not enough and when the aperture is also at its widest and still the image is too dark like here the shutter speed is around one-tenth of a second and aperture is F 1.7 still the image looks quite dark.
That’s when ISO comes into play. There will be noise in the image if you increase ISO but at least the image will be using it won’t be dark. Camera shake is not the only limitation for long shutter speed.
It also depends on what you are trying to capture. If it’s a moving bus or car then setting it to one-tenth of a second will end up blurring the subject.
Sometimes people intentionally increase the shutter speed to like three or four seconds to capture this kind of images “Light trails”.
So, what happens here is during those three seconds the light source travels from left to right. So, the entire trail is captured.
So anyway, I think you get the relationship between aperture, shutter speed and ISO.
Now depending on the scene, you need to adjust the parameters accordingly.
What is Optical Image Stabilization (OIS)?
Now the next thing is optical image stabilization. Remember I said the maximum shutter speed for a blurred free image around one-tenth of a second for a typical smartphone.
Well if the smartphone has OIS then you could go higher. Higher as in one-sixth of a second, one-fourth of a second, the reason for this is OIS make sure a dedicated motor inside the camera.
The motor makes sure to compensate for minor shakes. Note the word minor so if you’re capable of getting a blurred free shot at one by ten shutter speed without OIS then with OIS you can probably go up to one fourth or even one-third of a second maybe even one second if your phone’s OIS is really good and you manage to keep your hands super stable.
What is Underexposed and Overexposed?
So, now if you have completely understood the term exposure, now I am sure you’ve heard of terms underexposed and overexposed.
If you don’t know what they mean share me out.
let’s pull up a picture, a typical photo should ideally have both highlights and shadows exposed properly like this one.
The brighter parts of the image are called the highlights and the darker regions are called the shadows.
So, let’s pull up another photo.
In the first image, the highlights are blown out there is no detail nothing is visible it’s all just pure white so we say this part of the image the highlights are overexposed
Similarly, in the second image, in some parts, the shadows are way too dark which again leads to loss of detail in those regions so we say the shadows are underexposed
One of these issues happens when the scene you are trying to capture has a very bright object and a very dark object.
Sometimes people intentionally underexpose the subject for something like a silhouette.
So, underexposing or overexposing a scene doesn’t always mean it’s bad exposure. If you’re creative and make something cool out of it it doesn’t matter.
But typically, in most scenarios, we should try to get the best out of both highlights and shadows which brings us to the next term dynamic range.
What is Dynamic Range?
Dynamic range is the difference between the lightest tones and the darkest tones of an image I know a single line doesn’t explain it.
So, we’ll go deeper let’s say a scene has these tones of light.
The shadows of the scene are as dark as no 20 and the highlights of the scene are as bright as no 1.
A camera may not be able to capture everything perfectly. It will either overexpose a part of the highlights or underexpose a part of the shadows.
let’s say a camera is capable of covering tones in the range 5-16.
so, the dynamic range is around 12 stops which means the camera is capable of covering tones in any 12 consecutive stops.
so, if it’s the Middle’s 12 stops then you lose a small part of the highlights and a small part of the shadows.
You can increase the exposure and capture the shadows so these stones are covered but more of the highlights will be overexposed.
Similarly, if you decrease the exposure instead then you will be able to capture more of the highlights but the shadows will be underexposed.
Usually, the dynamic range of smartphone cameras are poor and that’s why a concept called HDR came up.
What is High Dynamic Range (HDR)?
HDR is nothing but a high dynamic range. Almost all of our phones have the HDR feature what it does is capture two or more images with different exposure settings and then merge them to get a nice result.
so, I shot these four images individually with different exposure settings.
Merging them resulted in this picture.
The dynamic range here is much better than any of those individual images.
But then this is a manual process I shot everything separately used Photoshop to merge it. But we all know phones can do it instantly.
This is the difference between a non-HDR image and an HDR image.
It makes so much difference.
Well, Dynamic range is one of the most important reasons why professional people like to shoot during the golden hours the one hour after sunrise and the one hour before sunset because during those two hours the sunlight is kind of soft, it’s not very harsh.
The highlights are not too bright and the shadows are not too dark.
Now one more thing is the HDR feature on smartphones it completely depends on the software. Tt’s up to the camera software to enhance the quality.
Google’s HDR Plus and Apple’s smart HDR are two of the best HDR implementations so far in my opinion of course.
That’s the reason why so many people are installing the Google camera app on their phones.
But guy it is very important to note that high dynamic range doesn’t always mean it’s better. Dynamic range is the most important thing in photography the term comes up everywhere.
What is Focal Length?
So, focal length determines the field of view. It is the angle between the two opposite corners of an image.
Here’s the table with different focal length values and their respective fields of view.
The primary camera on most phones has a focal length of 24 to 27 millimetre. On some phones, there’s a secondary camera with 2 X optical zoom like the galaxy s9 plus, iPhone XS.
What’s the focal length of those cameras? It’s easy just two times the focal length. If it’s 2X optical zoom it’s 2 times the focal length of the primary camera.
If the primary camera has a focal length of 25 mm then 2X optical zoom means 50mm. Similarly, wide-angle cameras have less than 25 mm in focal length.
On the Mate 20 Pro and the LG V40, the wide-angle camera has a focal length of just 16 millimetres which means the field of view is very wide 106 degrees. The actual focal length of the lens is very low 16 mm is just the 35 mm equivalent focal length.
What is Focus?
Focus is something I’m sure everybody already knows. When someone says the subject is in focus it means it’s one of the sharpest parts of an image
Generally, the depth of field where the camera can maintain focus depends on many factors. A wider aperture means the depth of field is very shallow. A bigger sensor also means the depth of field is shallow.
A professional camera with a big sensor has a quite shallow depth of field so the background blur is excellent.
But the sensor size of a smartphone camera is relatively too small so if you capture an image with smartphone comers everything in the background will be in focus.
But sometimes if the background is blurred out, the subject will stand out. It will look much better.
That’s why portrait mode is becoming increasingly popular these days. But then portrait mode is just a software feature. It just detects the edges of a subject keeps it in focus and then blurs everything else. it’s available on almost every new smartphone.
As you go closer to a subject even on a phone camera the background blur becomes stronger even without portrait mode. In case of a DSLR, it’s even stronger.
But then you can’t go too close to a subject most cameras tend to lose focus in that first 5 to 10-centimetre range from the camera.
For that, you need a macro lens or an attachment to an existing lens. Some cool accessories let you capture these kinds of pictures on your smartphone.
What is White Balance?
White balance is just a parameter that helps in making the colour of a scene more natural.
for example, here are two different pictures shot in different white balance settings
This is how the scene was when I shot the picture.
This one doesn’t look accurate it’s cooler.
So, what we need to do is adjust the white balance settings. See at which value the image looks good and click it.
These days on most phones white balance is set to auto mode and it does a great job.
What is Pixel Size?
Pixel size the name says it all. It’s the size of an individual pixel measured in microns.
For a given sensor a smaller number of pixels means the individual pixel size is large and high pixel count means the individual pixel size is small.
That’s why these days big brands like Apple and Samsung don’t come up with ultra-high-resolution cameras like 16, 20, 30, 40-megapixel cameras on their flagships because they give importance to the pixel size.
Why? It’s simple, large pixel size means it can capture more light which helps a lot in low-light. Mate 20 Pro has a 40-megapixel camera but it still performs well under low-light.
How is that? Well, it doesn’t exactly capture low-light images at 40 megapixels. The phone combines four neighbouring pixels into one, so effectively it’s just 10 megapixels.
Of course, it’s not the same as a native 10-megapixel sensor but still, it does make a little bit of difference.
What is Saturation?
Saturation is another term that we hear very often. It’s the intensity of colours. It’s basically how colourful the colour is.
let’s say I capture this thing.
This image represents the red accurately means the saturation is perfect.
But this is oversaturated
This is undersaturated
Zero saturation means it’s a black-and-white image.
so, we are done with all the major terms. let’s now cover some minor not too important terms like bokeh.
What is Bokeh?
When you shoot something that’s not too far away from the camera at a very wide aperture then the background is blurred out this is something we already spoke about.
If there are lights in the background, they tend to appear like circular light balls that are called Bokeh.
What is Aspect ratio?
Aspect ratio is nothing but the ratio of the width of an image to the height of an image.
Most smartphone cameras click pictures at 4:3 aspect ratio.
Now an important fact here, some people think changing the aspect ratio to 16:9 on their phones will capture a wider scene, but they are wrong.
What happens is the 4:3 picture is cropped at the top and bottom which results in our 16 9 pictures.
What is Viewfinder?
it’s the little thing that you look into to have a look at the scene before clicking the picture. On a smartphone, the display itself could be considered as the viewfinder.
What is Shutter release?
You don’t hear this term often these days but still, it’s the thing that triggers the shutter to open up. I.e. Shutter Button
What is Exposure Compensation?
I told you we need to adjust shutter speed aperture and ISO depending on what kind of a picture we need like widen the aperture if you want a strong background blur, decrease the shutter speed to reduce camera shake and so on.
But if you don’t care about all that if you just want to brighten or darken the scene change the exposure compensation value or EV.
There’s a dedicated knob for that on most professional cameras. On smartphones, we just need to use that slider which pops up when we tap to focus.
What is Frames Per Second (FPS)?
A video is made up of multiple photos the photos are called as frames here.
So, in a 60 FPS video every second has 60 images, in a 30 FPS video 30 images are displaying every second and as the number of frames goes up the video looks smoother but for regular usage, the most common values are 24 FPS, 30 FPS and 60 fps.
I think that I have covered almost everything. if you’ve got any doubts or queries feel free to let me know in the comment section.
I’ve put so much effort into the making of this, so I want everybody to share it on Social Media.
I think you have learned something from this. I will reply with an explanation – whichever comment you post.