What Photo Format Should I Use

-- by Jon --

There are a number of factors to consider when choosing which format is best when it comes to saving photos. I personally use the JPEG (or JPG) format. There are things you should know about the JPEG format before you start scanning and working with these photo files. Also see the article, Thoughts and Advice On Scanning Pictures It also has a few thoughts on what DPI (resolution) to scan.

For my purposes, I want sufficient quality for viewing on the computer screen and for printing. When you save an image as a JPEG file in a photo software for example, it will compress the file to make it smaller. The file will actually lose a small amount of resolution each time it is saved in the photo software. Please note, this does not mean that every time you send it in an e-mail or make a copy of it on a floppy or CD that it loses resolution. The regular copy process does not go through this file compression each time. It merely copies how you last saved it the last time you were in your photo software.

So let me illustrate how you could progressively lose a noticeable amount of resolution with an example.
Let's say that I scan an image into my computer and save it as a JPEG file. For any of my purposes, it is of very good quality. Now, I decide to crop the edges of my photo. I bring the same file back into the photo editor, cropy the image and then save it as a JPEG once again. The file compression takes place again, and a little resolution lost. Next, I decide enhance the same file again to remove some "red eye" and lighten it a bit because it is a little dark. I then save it again as a JPEG, and it again goes through the compression process and loses a little more resolution. If this happens over and over then the photo may begin looking washed out and not so sharp.

JPEG still happens to be my choice for saving photos and here is how you can get around the problem of losing resolution in this format. It is recommended that you keep your original scan file and save it for future use. If you ever want to crop the image or enhance the photo, go back to the original scanned image file and start from there. That way, you will always have just the one step from the original image and any loss of resolution should not be noticeable.

Another way to avoid loss of resolution is to save it as a TIFF file (or TIF). This format does not compress the file, nor does it lose any resolution as you save and resave the image. The down side of this is that the file is much larger than a JPEG file and therefore takes up much more storage space. This can fill up a CD quickly. As DVDs become more common the space issue may go away eventually. But if you are making DVDs or CDs for others, you must consider your recipients, do they also have a DVD drive in their computer.

It is recommended by many that you first save an image file as a TIF file. Then make all your changes you want, saving it as much as you want, then when you are ready to add it to a project on a CD, you can then save it as a JPEG. If you need to tweak the photo again, go back and tweak it as a TIF and then save it as a JPEG again.

For my 'special' pictures, this sounds like a good idea, but for my hundreds of 'run of the mill' photos, I choose not to worry about that step and just save to the JPEG to start with.

One more thing to consider. JPEG files can be saved at different compression levels. High compression would produce a lower quality photo, lower compression would produce a higher quality (with less resolution loss). Usually you can adjust this by doing a "Save As" in your photo software. On the save screen if the save type is set to JPEG or JPG, then there will probably be another button called "advanced" or "options" and there you can change the setting.

Smaller, high compression (lower quality) have their place. I may place these on the web to speed the loading and viewing time. To make it more efficient. It may be all the resolution I need.
In the end you must experiment and decide for yourself.