Photos Tartare
6 Apr 2006

Sorry. It's a terrible pun. It's even worse, because I have to explain. Food photography. Raw files. Yes, it's OK that you are grimacing. I am too. I briefly touched on Raw files in one of my last posts and some of you may not be familiar with what, exactly, that means. Raw files are the exact data that the image sensor in your camera records, in essence they are the digital equivalent to your film camera's negative. Really, they aren't anything like a negative... film negatives are actual images even if they are reversed out. Raw files are scary math algorithms. With a film camera, a 35mm negative is pretty much a 35mm negative and you can take it into any lab to get your prints. But with a Raw file, each camera is different. Each manufacturer (and even each specific camera) uses it's own unique algorithm to save the image data and write it to a file. These files then have to be converted into another format in order to be viewed or edited. But, at a core level, there are similarities. They are both the closest you can get to the what the camera sees and they are the source from which you can always go back and produce your "developed" images. As a result, you'll often hear people call Raw files a digital negative. Point and shoot cameras rarely give you access to this digital negative. Instead, they convert the data to JPEG files. You can think of this kind of like a Polaroid camera... there is no negative, just a positive image that you get to see and use immediately. Any digital SLR, on the other hand, will have an option to store your photos in that camera's Raw format instead of converting to JPEG on the camera. The conversion process from Raw to JPEG is fairly processor intensive. Cameras are designed to do this quickly, but as a result they don't always give the best results. By delaying that conversion, and performing it on your computer, you have the potential to get better results. Shooting in Raw gives you much more flexibility to adjust your photo after the fact (on your computer) because it's not just pixels recorded... it's what the sensor actually captured plus all the configuration settings you used. You can completely adjust for the color of the light and even adjust the exposure two or more stops without dramatic quality loss. In fact, many of the things that you could set in the camera menu can be adjusted later on your computer. Raw also stores more color information, although you may be hard-pressed to see the difference since most displays and printers can't actually use all of the colors. (If you want to get a deeper understanding of Raw files and color bit depth, check out this article from Cambridge Color.) In fact, I was going to put an example here, but the two images would really just look the same. The main reason you may want to keep this extra data is to future-proof for a time when printers and displays improve. There are also significant disadvantages to Raw as well. Raw files are larger than JPEGs, so you get fewer photos per card and it's slower to move the files around. And since they aren't standard image formats, Raw file still have to be converted before they can be used. In the early days of Raw files, this meant using an application to open, tweak, convert the files before doing anything in Photoshop. These days, most photo apps (iPhoto, Photoshop, Digital Image Suite, Picasa) have some basic Raw support built in so if you are shooting with a Canon or a Nikon this process is fairly streamlined... but it's still slower than using JPEGs. Over the past couple of years, I've gone back and forth between shooting just JPEG and shooting Raw and frankly, there isn't a clear winner on what is better. Right now, as of about 2 weeks ago, I'm back to shooting Raw. I'm really doing this for one reason. I might want to go pro some day. And, if that happens, I'll want to submit some of my work to a stock photo agency, like Stock Food. Most stock photo agencies, if they handle any print work, want TIFF files and I'm not going to be able to pull a good TIFF from a JPEG. Everything else that I do with my photos today, I'd be just as happy with shooting JPEG directly... I'm merely trying to future proof a bit "just in case." So, should you shoot Raw? Look at your needs. If you think that you may want to go back to the photos and get more out of them some time in the future and you are shooting with a Canon or Nikon (and therefore have a large number of software applications with built in conversion), it's probably worth the extra storage space and conversion time to keep the Raw files around as a backup. Otherwise, you should probably pass. In fact, even some pros think this is too much hassle, and shoot only JPEG. So, if you are just using your photos to share on Flickr or your own blog, save yourself the time and shoot JPEG directly. The camera will do a good enough conversion job for you and you'll use a lot less disk space and have fewer photo-management headaches. Hopefully, someday the camera industry will develop some standard way of recording images without data loss in a compact format that is immediately usable... but until then, you'll have to make a choice.

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(In case you were wondering, I am an Amazon affiliate, and purchases from links in this post to Amazon may earn me a nickel or two... so thanks!).

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