| JPEG verses RAW |
| Intro Many new photographers ask which is better. Many experienced photographers give mixed opinions based on personal preferences. My goal is NOT to tell you what to do, but to help you make an informed decision. What is JPEG? JPEG is a computer image compression method invented in the mid-1980s. The term JPEG is an acronym for Joint Photographic Experts Group. JPEG uses a codec to encode and decode your image files, making them smaller, thus, saving space on your PC. An image is already a binary file, so to compress it into smaller space, information must be thrown away. Permanently. However, if you only plan to use the file on your web page, in the upper right corner, then nobody will ever notice the lost details. But. If you plan to print 8 x 10 or larger, then you will definitely notice the difference in details. What is RAW? RAW is how your digital camera ( or other image capture devices) originally captures all images. Even your mobile phone camera depends on RAW images, then converts the file to JPEG. Conversion from the original is the key concept you need to understand. Any conversion has a risk of lost information. Even converting from large RAW to smaller RAW will have lost information. Only the original full size RAW file is a pure image with no lost information. Impact of Editing Just to give a clear example, let us imagine you want to enlarge the JPEG image file to double the size of the original. The software must add information to make this happen. That means the software needs to guess what to add to maintain the original image details. Not all software is the same. Some can do a good job at enlarging, but many can not. So we saved the file, edit it some more, look at it a few days later, then decide we do not really need the larger size. When you make the file smaller, it must throw away information. It will not throw away the added information only, it will also throw away original information. Now you have a very damaged image. Take this above example and imagine the work your camera must do when you tell the camera you want a smaller file size. The camera must throw away image details to make the file smaller. The camera uses software that is no different than your PC photo editing software. Not only do you have a damaged image, you no longer have an original RAW file. Suggested Work Flow Always shoot RAW. Use professional software such as LightRoom to review and manage your photos. Obviously, you will need to go through all your photos and delete ALL bad images. If the photos were only family and friend snap shots, you can convert to JPEG and delete the RAW images on your PC. Only save the best of the best RAW images for later editing (even edit again years later). Sinse a RAW file can not be edited, you never lose the original. Lossless Editing No matter what you hear, it is impossible to use the JPEG image file format for lossless photo editing. If you want true lossless editing, use the TIFF image format instead. However, there is a trade-off. The files are much larger, sometimes more than 10 times larger. When using layers in Photoshop, the amount of disk space required is exponentially larger. We are talking about more than 1GB for only one photo that you are working with. With large files, processing the image will be much slower. You will need a very fast PC with very large hard disk drives. After you are finished editing, save the final in a TIFF image file, then delete all the working files. Backup the TIFF image files to CD or DVD, then convert them to JPEG for use on the internet. |