Image Quality Settings

Discovering North Yorkshire through Photography and Video

Image quality settings are important because even if we have a fantastic scene with an attention grabbing composition, we still need to reproduce the scene in an image perfectly. In the old days of film cameras, high sensitivity films were useful but also contained grain. In digital terms, grain is now known as noise, and it is noise that is far more complicated than grain in film based photography.

The Causes of Noise in Image Quality Settings

Image Quality Settings

We’ve discussed previously that you should never use a high ISO in low light or night time shots because the image will over pixelate causing a noisy photo. Noisy photos are not pleasing to the eye in way, so we need to prevent this. However, noise can be caused by other factors too including electrical field, heat and so forth. Noise, or small speckles in the image will obscure detail and unless you have a particular purpose for it, will compromise quality. In the old days of film, photographers would go out of their way to avoid grain. Today, in the digital world, photographers strive to achieve the same with noise, to eliminate it entirely.

One way to see noise is with audio. Most of us have some form of noise producing equipment at home such as a radio or a television set. If you raise the volume to its loudest setting, the quality of that sound is reduced and may even become crackly. Certainly, loudness aside, this is not pleasing to the ear in any way. This is exactly the same as noise in a photograph. Why? Well, when you increase your ISO in your camera, you are strengthening or increasing the signal as you would with volume control. It is that strong electrical intensity that causes the noise in your photograph. When you amplify the signal, you are amplifying the flaws in the signal too. This is why you need to ensure that you are using an ISO that is reasonable for the circumstances. Having said this, there may be times that you want to include a measure of noise in your photo for creativity purposes. This of course requires experience on how you can use noise to your benefit.

A point to keep in mind is that cameras differ in quality too, so what works in one camera may not work in another. In any case, it is good to take your camera out in the field and see just how high you can go with your cameras ISO without it resulting in too much noise. ISO differs in cameras sometimes owing to the size of the sensor itself as well as pixel count.

Nighttime ISO

Image Quality Settings

During early morning, twilight and nighttime shots it is best to go no higher than 200. Many photographers use Aperture Priority mode at nighttime. This might seem strange as you would possibly think Shutter Priority would be better when it comes to allowing in more light with a low ISO. However, we must remember, that if we set our aperture to f16 for instance, the camera would compensate automatically and extend the shutter speed for you. In this case, you can still maintain a low ISO as well as receive a sharp image throughout the scene. If you set your shutter speed instead to something like 2 seconds, granted you will receive enough light, but only because your camera will have automatically widened the aperture. In this case, the wide aperture will result in a photograph that is not sharp owing to the smaller focus area.

Image Quality Settings: This image was taken at night time with an aperture value of f11 and a shutter duration of 1/10th of a second. You'll notice that the image is noise free. This is because the ISO (light sensitivity) has been set under 200 ISO. If the ISO had been set much higher, noise would be evident in the form of speckles throughout the shot.
Image Quality Settings: This image was taken at night time with an aperture value of f11 and a shutter duration of 1/10th of a second. You’ll notice that the image is noise free. This is because the ISO (light sensitivity) has been set under 200 ISO. If the ISO had been set much higher, noise would be evident in the form of speckles throughout the shot.

Acquiring Detail

Image Quality Settings

One myth is that the higher the resolution the more detail you are going to receive. This is untrue, it’s simply the higher the resolution the more pixels you have and has no bearing on detail. If the lens is of poor quality, then this will reflect in your image regardless of the resolution. Just because you have more pixels it does not make the image sharper, and therefore quality and resolution are unrelated.

Image Quality Settings: Alfie's face has a great deal of detail to the naked eye, such as fur, whiskers, brown eyes and more. Having used high resolution does not guarantee that every detail will be picked up. However, the better quality lens you have, the better quality of detail will be returned.
Image Quality Settings: Alfie’s face has a great deal of detail to the naked eye, such as fur, whiskers, brown eyes and more. Having used high resolution does not guarantee that every detail will be picked up. However, the better quality lens you have, the better quality of detail will be returned.

Now having knowledge of this information may influence your decision about file sizes. You may assume initially that you should choose the largest resolution. However, remember that the larger the file, the more processing takes place, and also the more space it occupies on the memory card. If you are shooting a RAW and jpeg image simultaneously then you will need an ultra fast memory card to record them. Of course, selecting the medium resolution on your camera will assist in faster file writing too. To help you, it is a good idea to take the same photo in the largest resolution and the medium resolution so that you can compare the results. This will help you choose the correct resolution for future photographs.

File Types and Image Compression and Image Quality Settings

Image Quality Settings

There’s typically two types of files that record your images on your memory card, RAW and jpeg. Most professional photographers shoot in RAW format because this file type contains all the data from the shot the photographer has taken. As a result the file size is much larger, but it gives the photographer a huge amount of data to play with in applications such as Adobe Lightroom and other image editing software. As you have all the data there, you can manipulate it to receive the best possible rendering from your shot.

On the flip side of the coin is the alternative, that being jpeg. Most of us are aware of jpeg image formats as it is widely used and recognised around the world. However, in your camera, jpegs are somewhat lossy because the file size is greatly reduced. The camera processes the raw data itself automatically to produce a photo. The remaining jpeg image is based on how the camera perceives to be the best result. Jpeg images can still be modified, but to a much lesser degree than a RAW image as it is anything from a tenth of the size and contains far less data. Therefore, jpegs are lossy in terms of data and quality. With jpegs, it is often best to select the highest quality that being the lowest compression in your cameras settings.

Key Camera Skills

Camera Shutter Settings

Aperture Value and Depth of Field

Image Quality Settings

Mastering Colour Settings

Photo Sharpness

Thornton le Dale to Low Dalby Walking Route