To get a quality image you want to be sure to know what the technical requirements are for your electronic photos.
Technical Requirements for Electronic Photos

Some publications will accept publicity photos in electronic form, but you must make sure your shots are in a format they can use. Determine that by asking these questions:

Will the standard format of 300 dots per inch (dpi), 11 inches (either length or width), in a jpeg file saved at quality level 9 meet your needs?

Do you need color or black and white?

What density, in dots per inch, do you need?

What size do you need, in inches?

Do you have any other format requirements?

Is it OK to email the photo to you in a compressed file? Files containing digital photos are large. Don't email them to journalists unless you have their permission. Large files can jam email systems, and some media outlets automatically refuse to accept them. Let the journalist know how large the file is when you're asking permission.

"A 300 dpi, 11 inch photo saved at quality level 9 will be about 50k in file size, and thus can be emailed. The same photo saved at 12 is about 1.5M - too big to be emailed," says Andrew J. Carothers, President of The Carothers Group in San Rafael, CA. "In addition to emailing them, you can send photos to journalists on CD-ROMS."
Another delivery channel is to post photos on your Web site - and let journalists know about them in press releases and media kits.
For great tips and advice on how to make the your electronic images and photos meet requirements and look their best, see David R. Yale's report "How To Get Free Publicity For Your Products"