Why should I shoot raw? What is raw? Is raw better than a jpeg? My computer doesn’t read raw files. Raw files are the raw camera data directly off the sensor. This is the 1′s and 0′s that the sensor actually recorded before making it into a file with red green and blue data. Your image sensor is a grid of red green and blue pixels. They are layed out in a grid very tightly packed together. On average as of this writing they are 5 nanometers almost right next to each other (somewhere between 1 and 3 nanometers of separation). Each pixel has a filter on it. Red green and blue filters. So you will have a red pixel, a blue pixel and a green pixel in a row one after another. It gets a little more complicated than all that but for the sake of this blog just go with it.
So what does that all mean? That means that when the data is collected off the sensor it is not even a picture. It is just a binary collection of data. After you take the photograph your camera makes a rough judgement what the image would look like. This is the preview that you see on your LCD screen. Have you ever noticed that the image you see on your camera LCD looks a lot different than the one on your computer? That is one of the main reasons why.
So your raw file is a collection of raw data directly off the sensor. It is uninterpreted 1′s and 0′s of a grid of red green and blue information. Because this is not actually a photograph, only certain programs can show you what the image looks like. In order for these programs to work they must interpret all those 1′s and 0′s and blend all that red green and blue information into each individual pixel. That is where Adobe Camera Raw or Capture One or Canon editing software or Nikon editing software or Lightroom comes into play. These are all programs designed to interpret that information and spit out an image. After you edit and image in ACR for example you then can open the file in Photoshop or another photo editing program. What is happening here is ACR is creating a blend of those red green and blue pixels into an image file. Remember that a raw file is not an image file, it is just raw data off the camera sensor. When you open your image file, a PSD for example, and you do all your fancy editing and save the file, it is now a completely separate file from the raw file. In the same folder you will have the raw file and the PSD. No matter what you do to the PSD, the raw file will not change. It’s brilliant.
There is a lot of color information in your raw file, more than you will see in the final image but it’s there. Your PSD is an interpreted file from the original raw file. Essentially it is a copy of the file. If you were to save the PSD now as a jpeg it is another copy of a copy. But here’s the shitty part. Jpegs are designed to be as small as possible. One of the many things done to create a jpeg is eliminating all unnecessary data. Part of the process of creating a jpeg usually increases the saturation and the contrast of the original file. I am not going to go into the full details on that but think of it like this, shadows are blue. When your image editing software comes across these pixels in the shadow area it reads that they come out some shade of blue, or a blue tint. Therefore a lot of the yellow information (compliment of blue) is not being shown in the image file and therefore can be eliminated. If you are printing your shadows as blue then there is no problem with that. So now you have shadows with little or now yellow information, that you couldn’t see in the first place, but still have a lot of blue information.
But let’s say you don’t want blue shadows now. Blue isn’t a good color for people. I don’t know how the smurfs got away with it.
If you open your processed jpeg in photoshop now and suck out the blue, there is now yellow in those shadows to replace it. So instead of getting orange healthy looking people you get grey people. You desaturated the blues but there was no yellow to saturate in it’s place. Shooting jpegs in your camera is doing exactly that. But now you don’t even have a raw file to fall back on and start from scratch. Sounds like a bad idea doesn’t it?
If all of this sounds way too complicated try this instead. This is my generic response whenever someone asks me about shooting jpegs.
A jpeg is a compressed image file that eliminates most of the original data captured in
camera. As a result there is not enough information in the file to fully
color correct. The images have been edited to the best of their ability. Raw
files directly from the camera give the most latitude to accurately correct
files. Jpegs are 8 bit color, 72 dpi, and only around 4 stops of
information. A raw file is 12-14 bit color, 240 dpi, and up to 12 stops of
raw unprocessed sensor data that can be fluidly adjusted and give you a
higher quality end product.
I have heard some photographers say that they shoot jpeg because they like the compression of the jpeg and how it comes out. This is a very misleading statement. Here is what’s happening, the camera is taking the raw data and interpreting it. Like I said before one of the inherent factors of jpegs is to increase saturation and contrast. By increasing the saturation and contrast in camera raw you can achieve the exact same look as the compressed jpeg. I have a preset in Lightroom that adds this to every file that I import. This way you still have control of the original raw data if you need to adjust it. Real art buyers do not accept jpegs for their advertisement for this reason. Therefore we at Shrelp cannot accept them either.
-Zach Petschek
