A brief introduction to different image formats
At this stage we won’t go into too much detail about all the formats available because to be honest, you will probably only use two, RAW and JPEG. We go into the ins and out, benefits and downsides of each in the next module but here is a quick introduction.
Many people when they first buy a digital camera, set the image quality to fine JPEG which is the highest quality JPEG that the camera will take. All DSLR’s these days also have the ability to shoot RAW images and I would recommend that you start to use and learn to shoot RAW.
JPEG is the term given to an image file that has been reduced using a lossy compression. This means that all but the needed pixels of data are discarded leaving a great looking, high resolution image that is small in size (megabytes). Most cameras that shoot JPEGS will also enhance the sharpness, colour saturation, white balance and dynamic range to the best of its abilities.
The downside is that you lose a lot of information within the pixels meaning that it is less able to be manipulated.
RAW on the other hand, is the term given to an image file that has had no data extracted and remains exactly “as is” when the image was shot. All the data captured by your camera is still stored in the file meaning it is much larger in size (megapixels not dimensions).
This means that should you wish to make enhancements to the image, you have so much more data to work with and manipulate.
For example, when shooting weddings, cameras at the time of writing still have trouble distinguishing between dark shadows (the grooms’ suit) and bright highlights (brides’ dress). The human eye has no problem with this, we can see detail in the shadows and at the same time, find details in bright areas.
When shooting JPEGS in this situation, there is little information to extract so if highlights are blown, they will stay blown.
When shooting RAW, there is so much more information stored in the file that it is easy to pull back those blown highlights and in many cases, save an otherwise disastrous image.
RAW is good but you will need specialist RAW processing software. Adobe Lightroom, Photoshop and many other editing suites now have upgradeable RAW plug ins that work with most manufacturers. Some companies such as Canon will include basic RAW processing software with their cameras.
However, if you are in a constant lighting environment such as a studio, you can set the camera’s shutter speed, aperture, white balance etc. and keep the light source at a constant setting and shoot JPEGS all day knowing you won’t need to make any adjustments later…you have the correct exposure from the start.
I always err on the side of caution if the images are important to me and shoot RAW.
TIFF is another LOSSLESS format like RAW that used to be fairly widespread but is becoming less used. Alamy stock library only used to accept 50mb TIFF files as they were incredibly detailed and retained all of the information stored in a RAW file…except they were more user friendly than RAW files for most applications (magazine publishing for example).
Alamy now only accept JPEGS as the quality has improved over the years and is suitable for just about anything.
Next Page – Software