I am currently involved in an internet conversation between photographers in the Raleigh/Durham area on the benefits of shooting photos in the RAW vs JPEG formats. I must apologize in advance, as this post is going to get fairly technical, very quickly. I must also state that I am absolutely NOT in any way providing any ground-breaking information or anything that isn’t already widely known, but I have been “called out” to demonstrate in my own experience why it is best to shoot in the RAW format.
Just to get everyone up to speed, the average Digital SLR in the year 2012 can shoot both a RAW and JPEG format. Let’s start with the easier one to understand, the JPEG format. The JPEG format has been around for years, according to the JPEG wiki page, since 1992 (it seems like even earlier, at least to me). Standard JPEG files store color information in 8 bits per channel, which equates to 16.8 Million colors. Every time (including the first time, if you are shooting JPEG in the camera) a JPEG file is saved, an algorithm is run to throw away data in an effort to save space and make a smaller file. This is a “lossy” algorithm, in that data is irretrievably thrown away during this process.
The RAW formats are all manufacturer proprietary formats, despite the efforts by companies such as Adobe to try and push a standard format. As a history lesson, when the first DSLR cameras came out, the manufacturers wanted you to use their software to open their files and convert them to usable formats such as TIFF. You see, the RAW files that come out of DSLR’s are a dump of the information that the sensor sees at the time of the image capture. Things like white balance, contrast, color space, sharpening, etc are NOT applied to the raw data that is in the RAW file. Those settings that the camera is set to are, however, saved in the RAW file, but not not applied. One way to think about it is the camera settings are “hints” that are left in the RAW file, kind of as a starting place for your RAW converter. In order to actually open a RAW file, one must convert it. In the early days, you either used the software that the camera came with, or you used some hacks that were around that reverse engineered the formats. These days, (I think) the camera manufacturers actually work with companies like Apple and Adobe to have 3rd party integration of the raw converters into their software, as well as still providing a software program that will convert the files with the camera. I still remember the distinct pain in the rear it was to work with raw files and older-than Photoshop CS (such as Photoshop 7, which was crippled in editing anything with a larger than 8 bit per channel color space). RAW files store their color space in a 16 bit space, but most DSLR’s don’t use all of it. The camera that I utilize as my primary camera is the Canon 5D II, which uses 14 of the 16 bits of space. This gives 16384 colors per channel (there’s 3 channels, Red, Green, Blue). So, the JPEG has 16.8 Million colors, a Raw file from a 5D II can record up to 4.3 Trillion colors.
Can you actually SEE the difference between 16.8 Million colors and 4.3 Trillion? No way, Jose. So why do I care? The answer is, it’s all in the edit, and also in the final use. I used to set my Canon 5D II in the “RAW + JPEG”, and to show an example of why I do this, I pulled an image from the time period when I did shoot in this way. Just as background info, I used to shoot RAW + JPEG because I thought the time that Lightroom took to manipulate images might be sped up having both files. I have come to the conclusion that it either doesn’t speed up, or that it doesn’t do so in a discernible way, so I just shoot RAW only these days.
This image is from my 365 project, back on May 25th, 2010. In this image, I over-exposed the subject somewhat and had to pull information in post processing to make it look better. Had I just shot in the JPEG format, there would not have been enough detail left in the color information in this image to “fix it” satisfactorily. There was, however, enough data left in the RAW file to help me out in the post processing. Luckily, I shot in both the RAW and JPEG format in the camera, so I can use this image as the example in this blog post.
Here’s the finished image, as I finished it for you post during the 365:
The right side of the image had a strobe which created a gigantic amount of flare and also the exposure of that side of the model’s body, especially the arm, was very close to completely blown out. By blown out, I mean that the pixel’s colors would be pure white, thus devoid of details. In the JPEG version saved by the camera, that area of the model’s arm is indeed blown out in 2 of the 3 color channels. I have pulled these files into photoshop and using the curves tool you can see the clipping, which is another way to say blown out.
See in the image above, that photoshop reports clipping in the skin details of the subject in one channel, and in two channels on the arm area.
It is apparent here below visibly as well on the jpeg file (which was saved and just opened in photoshop, no changes made).
Without making any adjustments in photoshop, besides opening (which does apply adjustments by definition), the RAW file from the camera shows much less clipping (blowing out):
Notice how the face, and the arm except for the “rim light” on the edge is black here, which indicates that there is data to be used. Even with no adjusting, you can just see that there is more data, see below:
After manipulation, we get a usable arm and the face has details using the raw file. Had I not shot in the RAW format, I would not have been able to have nearly the quality output as what I had.
Using RAW is not just valuable in the edge cases like this, you also get to adjust the white balance, contrast, sharpening at your leisure (if you shoot JPEG in the camera, those settings are “baked into” the image, and there’s no adjusting after the fact). You also have every pixel to use, whereas with JPEG, you have a compressed file where much of the data is completely lost to the great bit bucket in the sky.
I shoot RAW and convert later, because it is much easier than it used to be. Long gone are the days where we are tied to the Canon converter or using reversed-engineered hacks. Adobe has integrated the raw converter into Photoshop since Photoshop CS and they also have an amazing product in Adobe Lightroom. Lightroom lets me import the RAW files, make adjustments and then output JPEGS with great ease and speed. If this were still the year 2000, in the days when computers had less ram, less processor speed and power, less cores and hard disks didn’t top out in the multiples of Terabytes, then the argument could be made that shooting JPEG, for most situations, might be OK. That time is over, the computers these days, both hardware and software, slice through the RAW files with great speed, and the latitude that you keep by shooting in RAW is worth every 1 and 0 they occupy on my hard disks. I care too much about the photographs that I shoot to not have the highest quality photos at the end of the day.