The following articles were posted in Photomart’s Photoweek on 20th March 2009 but still ring true today so we though we would bring them back again for 2010.
A Time and Place
Ian Arthur – Ian Arthur Photography
In life there is a time and place for everything. The same applies in photography, especially with the type of image file that your camera will capture. Should I capture JPEG or RAW? First off, what is a JPEG? This is a file that can be made smaller to varying degrees. It does this through something called Lossy Compression (lossy meaning “with losses to quality”). The compression uses mathematical equations called algorithms, and depending on what level of compression you want, the algorithms decide how much data to remove from the file. The easiest way to explain is that when the file is closed, a cluster of pixels will remember the colour of its adjacent clusters of pixels and so when closed, those adjacent clusters of data are thrown away – making the file smaller. When the file is opened, each remaining cluster provides the data to bring those pixel clusters back into place again, making the file bigger.
So, what is a RAW file? The easiest way to imagine a RAW file is that this is an uncompressed file that is captured at the cameras full resolution. So what’s so special about this? Well, when you open it in specific processing software – such as Adobe Camera RAW – you can add or take away levels of exposure, density, saturation, contrast, sharpness etc, which gives the photographer a lot of control over the image, especially over colour balance. So, how are they used? JPEGS are used mainly with small cameras within the amateur market, but PRO’s tend to use JPEG’s for Press and social photography, or where a quick turnaround is needed. RAW files are used by professionals for most types of photography and where image quality and content control is important. What are the drawbacks? Well, if you compress a JPEG too much it will degrade the quality. Also, each time you edit and save a JPEG, it re-analyses itself and this will start to degrade the image. It isn’t noticeable at first, but after several edits you will start to notice the difference. There are no technical disadvantages with RAW files, the only disadvantage being the size of the files and the cost associated with storing or transmitting these large files. And what are the advantages? Well a JPEG is like a small sports car – its fast, light, manoeuvrable and easy to park, but its easily damaged and not very hardy. A RAW file is like an estate car – much slower and cumbersome, but it will get you there in the end and because of its luggage space, there’s so much you can do with it. Like I said, there’s a time and place for everything….
Confidence or Common Sense?
Al Birmingham – Al Birmingham Photography
For some, RAW vs. jpeg is about confidence, for others it is about common sense. Most wedding photographers will often tell you it is common sense to use RAW, you can correct all but the worst exposure errors and you don’t have to worry so much about colour balance at the time of exposure. Other wedding photographers will tell you that you shouldn’t be doing weddings if you can’t get the exposure right first time. Obviously family snaps needn’t be in RAW and cameras are getting better at white balance with every model so perhaps the days of RAW are numbered anyway. If you feel the need to play safe in a situation, use RAW. If you have full control e.g. shooting in a studio or if you don’t need to worry too much about the final result use jpeg.
A Rule of Thumb
This is one of those debates that will go on forever because without knowing when and where it is going to be used there may be a different answer.
With the latest cameras commonly offering 14 bit RAW and a minimum of 12 million pixels the file size would be about 25MB uncompressed whereas an 8 bit JPEG would be about 5.7MB (optimised for quality), so the RAW files are taking slightly more than 4 times the memory. With a 4GB card this means that you will get about 150 RAW or over 600 JPEG images (compression not considered).
A JPEG should be considered as a processed file, the camera has made a decision about what to include or not and if the photographer has set the camera correctly what is produced is a file that is ready for printing. The RAW file in comparison is much more like a film negative that can be developed in many ways to suit the photographer’s requirements. Due to the dynamic range that has been captured in RAW it is easy to correct for an amount of under or over exposure.
As an Event Photographer what is normally needed is to get the images to the computer and quickly available to the customer. Smaller file sizes and a requirement for minimal or no processing means that an optimised JPEG, typically no more than 1.5 – 2 MB will give all that is needed to print on site up to 12” x 8”.
At the other end of the scale we have the wedding photographer who is often dealing with constantly changing light levels and light sources and the need to correctly expose for a Bride in a white dress and a Groom in a dark suit. The ability to have total control over such things as white balance and exposure for images that do not have to be delivered immediately, make weddings an obvious candidate for using RAW.
There is a middle ground of where images are taken and printed at an event and then may at a later date be ordered in larger sizes such as a 24” x 36” canvas. It is quite possible to get such enlargements from a JPEG from a modern DSLR but some prefer when shooting wirelessly to send the JPEG to the computer for on-site work and save a RAW version on the card for any later large prints, after all disk storage is getting cheaper all the time.
As a rule of thumb, ‘Shoot RAW where you need to & the rest on JPEG’.