In one of my many other lives I am a hobbyist photographer. (Shameless plug in case you live in the Bay Area) I only say hobbyist because I don’t make enough income to be considered actually professional. For me the thrill is seeing the image on the screen after the session is done. While I know technically what I am doing and know that I am capturing great priceless moments, it’s still nothing compared with the feeling I get when I see them large and on my machine at home. So . . . the burning question is what are the main different files and which one should I use?
There are really lots of choices. So let’s break it down.
The biggest “picture” files are RAW files. Called NEF for Nikon and CR2 for Canon (if you want to see other names check out this wiki) RAW files are only useful if you have a special program to open them. They are the digital equal of film negatives. And just like film negatives don’t do anything for you at home neither will RAW files unless you have a computer program to convert them (ie. Adobe Bridge, Lightroom, Picasa). The advantage is you can change things about the “negative” like brightness, contrast etc without losing quality. It’s a great thing. But please don’t ask your photographer for these, because any reputable person would never, ever give you RAW files. And they are HUGE!!
The most common image file you see is JPG. These are good. The disadvantage is the files are compressed to make them a reasonable size. It is considered a lossy compression because there are tiny pieces of the big file that are lost to make the file the reasonable size. While this will only really matter if you plan to print a poster or billboard from them, that is still something you should know. One big thing to remember is that you can not have a jpg with a transparent background. This matters for logos, buttons, and banners you make for your blog or other websites. JPG files will always sit on a color. So keep this in mind. But just know that I happily print 16×20 prints from my JPG files saved at 300 dpi (which should be next weeks term to explain but quickly means dots per inch). If you are lucky enough to find a photographer who sells you digital files they will most likely be JPG.
GIF files are also compressed digital files, again meaning down to a reasonable size for your hard drive (unlike RAW files). The advantage to GIF files is they don’t lose data like JPG files. The disadvantage is they will take a bit more memory space. GIF’s are great for graphics and digital art. If you get all fancy you can even make animated GIF files. A lot of the “blinkies” that you find in signatures on forums are animated GIF files. Since GIF’s are used mostly for graphics these types of files are better choices for your logos! Big plus – They CAN have a transparent background. Which means your logo, button, badge, or banner can have nothing behind them and they will be able to sit on any website without an unpleasant box around them. Just know, they aren’t really used for digital photography though.
And finally for today’s installment – PNG files. These are another form of graphic file. Again not losing any data but compressing “better” than GIF. Essentially they are similar to GIF in that you can have transparent background. PNG is preferred for the web for technical reasons (which are more than I understand) but just know that when talking to your designer or designing yourself its best to use PNG for your more important files.
Hopefully this makes a little sense as you try to understand the different files and why it matters that your designer or photographer offers you things with different names. JPG is the standard for photos and either GIF or PNG are generally preferred for branding and graphic work.