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This setting not really photographic but is, in fact a function of the jpeg format that most digital images are stored in. Tiff and Raw format images just have one quality, maximum. Only with jpeg images can you actually control the quality of the final image. Although the setting is called quality, that is not actually what you are controlling when you adjust it.

The jpeg format is remarkable. Not only does it store the information from your image so that almost anything can read it but it can also compress this information into a smaller space. It doesn’t make the image itself any smaller (only the size control does that) but it does make the image file size smaller so you will be able to store more of them on the same sized memory card. This is the only real advantage of using a low quality setting on your camera.

I find that the easiest way to visualise what’s going on is to think of a photograph printed on paper that you then crush and put in a small box. When you take it out the box and unravel it, there will be some creases on it. If you crushed it to fit in an even smaller box, it would have more creases and be lower quality. This is more or less how jpeg works in practice except you don’t get creases on the image. What you get are jpeg artefacts. There are two forms of these. One is odd wiggly lines around any well defined edges the other is what looks like square blocks on areas that should be one flat colour.

 

The best thing about jpeg is that, if you use low compression (high quality), the image hardly suffers at all. Most people wouldn’t notice anything wrong yet the file can be as little as 10% of the size of an uncompressed file. Allowing your memory card to hold 10 times more pictures.

 

The worst thing about jpeg is the fact that the artefacts it creates in your image are permanent and part of the saved image. This is important if you intend to edit your image and save a new version. Every time you save a jpeg, whether in your computer or your camera, you create these artefacts. So, if the image was a jpeg to start with, after some editing you might find the final quality to be less than you expected.

 

Camera setting

The quality setting on your camera is usually found in the main menu near the size setting. If your only aim is to get the maximum number of pictures on your card, then both size and quality need to be at their minimum to achieve this. Quality options usually consist of low, medium and high. High is the one you need if your pictures are intended for anything other than personal use.

 

For those who don’t intend to edit, publish or sell their pictures, it’s just a matter of personal taste. If the low quality setting looks good enough to you, then use it. You will gain space for a few more pictures on your card.

As with the image size setting, the quality is often set to medium by default. This compromise is unlikely to suit anyone. It is much more likely that you would want either the best quality or the greatest number of images on your card. The medium setting gives you neither.

 

Other file formats

In most cameras, the quality setting affects the way your digital images are saved in the jpeg format but some cameras can save images in other formats, notably tiff or raw. In terms of quality, both these formats represent the highest your camera can produce, but they are quite different from each other. You are very unlikely to have both options in your camera, but your highest quality setting may be producing tiff or raw image files.

 

Tiff

The tiff format is uncompressed. That is the main difference between it and jpeg, but it’s a big difference. An uncompressed image file is enormous even when compared to a high quality (low compression) jpeg. So much so that it may be impractical to use it unless you have a large memory card installed. Also you may find that there is hardly any difference in quality between tiffs and jpegs with low compression. Tiff files are really only practical when you absolutely must ensure that you get the maximum quality image your camera can produce.

 

Raw

This file format is very different from the other two in that it needs specialised software to even see the image. This software should come with your camera or you can get it from the manufacturer. Raw is actually a general term for several formats. Each camera maker has their own proprietary version and they are not compatible; however, there are independently made programs that can read and process many different raw formats.

 

In terms of image quality, raw files are every bit as good as tiffs but usually not so large, although they are still much larger than jpegs. As long as you have the correct software and a large enough memory card, saving your camera images in raw format is the perfect way to guarantee maximum quality.

 

It is definitely worth checking the size and quality settings on your camera. There is an enormous difference between a small low-quality digital image and a large high-quality one. Which one you need depends on how you intent to use your photographs. One thing is certain, very few people will find the medium size and medium quality setting to be the best one for them but these are probably the settings your camera will have when you first start to use it.

 

Camera quality setting