As digital photography becomes increasingly popular, a problem faced by many consumers is how to turn those digital images into prints. You can certainly print at home using an ink jet printer, you can find a local store that offers printing or you can use one of the increasing number of online photo printers. Each route has its advantages and disadvantages.
Home printing
Printing at home using either an inkjet or dye-sub printer certainly gives you most control and provides an essentially immediate print. However there are drawbacks. One is the longevity of the prints. While premium inkjet prints printed on the right paper and stored and displayed under the right conditions can have a lifetime measured in decades before any noticeable fading occurs, it's also possible to produce inkjet prints that start to fade in a matter of weeks or months. A second drawback is cost. Ink isn't cheap and neither is photo paper. It's quite possible to pay $0.50 for a home printed 4x6 print. A third drawback is you need to have some knowledge of how to color correct and/or color calibrate your system.
Local Stores
These range from your local supermarket to your local Walmart. There are both self service digital printing kiosks and full service photo printing departments. Service can be fast, ranging from a few hours to a few days and pricing is generally in the range of $0.15 $0.25 for a 4x6 print. Many of these services print on real photo paper and the longevity of prints can exceed those of home printed inkjet prints, even when stored and displayed under non-optimal conditions. The disadvantage is that you have to drive to the store and wait, or drive back again later to pick up the prints. Print quality may also vary from store to store depending on how good (and how interested in their work) the staff of the photo department are.
Online photo printers
There are now numerous online printing services. Most of them allow you to upload images to their site, some even offer you 100s of megabytes of storage space for your images. If you don't have broadband, this can be slow and such storage should NEVER be used as th eonly method of archiving your images. ALWAYS keep local copies of everything. However uploading the images onto the photo printers server can be a way to share your images with family and friends. Again, these services usually print on "real" photo paper using photo chemistry and longevity is good. Many of them use the Fuji "Frontier" printers which print the digital files on conventional photo paper using red, green and blue lasers. These are "photographic prints" and so should last as long as prints from film do.
These days there's heavy competition between online printers and most offer not only a number of free prints to new customers, but also very low cost prints once you have to pay for them. The price of a 4x6 print has fallen to as low as $0.10, but more typically ranges from $0.12 to $0.19, which is cheaper than printing at home.
Since so many of these services offer a limited number of free prints, you can shop around and compare resulrs. The downside of these online services is that you have to wait for your prints, and if you're not happy with them you have the hassle of returning them. But that's just the same as mail order prints made from film, and many people are quite happy with that. Generally service is fast and quality is pretty good though.
What to send
All the online printers try to make things as easy as possible for consumers, so they can usually print whatever you send them. Most of them provide some sort of software for image preparation, but if you have your own image editing software, you may want to use that, since it's likely to be more powerful.
The first thing you'll probably need to do is to crop your image. DSLRs usually produce images with a 3:2 aspect ratio, while many consumer digicams produce images with a 4:3 aspect ratio. This is fine, but standard print sizes generally don't hav ethe same aspect ratio as the images, so something has to go! The one exception is for 4x6 prints, which will accomodate full frame uncropped shots from DSLRs.
This shows the cropping required when printing a 3:2 aspect ratio image from a DSLR as a 5x7" print. Cropping at the side (or sides) of the image is needed. If you don't want the printer to decide where to crop (they'll usually just center the image), it's best to do the cropping yourself.
This shows the cropping required when printing a 4:3 aspect ratio image from a digicam as a 4x6" print. In this case cropping at the top or bottom (or both) of the image is required to fit the paper. Again, if you don't want symmetrical cropping, you should do the cropping yourself rather than leaving up to the printer.
If you have broadband service, file size probably won't be a concern for you, but if not, you might want to resize your images (see this article on resizing images) before sending them. A good rule of thumb is that 300ppi (pixels per inch) will give excellent quality, so for a 4x6 print the file should be 1200 x 1800 pixels, for 5x7 it should be 1500 x 2100 pixels and for 8x10 it should be 2400 x 3000 pixels. If your camera doesn't have enough resolution for the larger sizes here, just send the largest possible file or upsize to 300ppi in your image editor using the post possible interpolation technique (as described in the article on image resizing). 3MP cameras make fine 4x6 prints and OK 5x7prints, but at 8x10 the lack of pixels can show. If you want to make a lot of 8x10 prints, I'd recommend a camera with 5MP or more.
Some cameras are capable of shooting in an extended color space called "Adobe RGB". This is fine if you are doing your own printing and if you have a color calibrated system including software and printer drivers. However most on-line printer want your images is standard RGB color space ("sRGB"). That's the default on most high end DSLRs and it's the only color space that most consumer digicams are capable of working in.
Most online printers prefer files be JPEGs. Many can also print TIFF files, though TIFF files are much larger and so slower to send. Some may even accept other formats, but there's really no good reason to send anything other than a JPEG file for most work.
