Use file types for specific purposes.
Since we are a print and photography studio we are not concerned with how many megabytes your file is and prefer everything to be as large as possible. TIFF files are preferred because they can hold the full color depth data given by the color profiles as well as preserving any adjustment layers that may have been added to the file.
JPGs are compressed to have fewer megabytes when they are saved, so they are purposefully smaller for ease of emailing or using on the internet. Since they have been compressed, they do not have the same volume of color data as a TIFF. Once a file has been made a JPG you can not go backwards to make it a TIFF and recover the color data - just like if you compress the image to shrink it, you can not go backwards and recover the pixel data.