Printing Digital Images (for beginners)

Reprinted from the Houston Underwater Photographic Society newsletter.
Do not reproduce without author's written consent.

Printing Digital Images – Mastering the Mysteries of Adobe Gamma, RGB Profiles, and Print Image Matching.

While the best way to share your photos is undoubtedly projected on a 20 foot screen, to the sounds of waves lapping on the beach and thumb piano music – a much more convenient and personal way to share your memories is in print. But as with everything else in the digital world, getting a good print at a good price requires a basic knowledge of digital photo fundamentals.

The Five basic concepts:

1) Format: Most consumer cameras shoot at a 3 to 4 aspect ratio. For example, my 3 megapixel Coolpix takes photos that are2048 x 1536. The camera can be set to take photos at the conventional aspect ration of 3 to 2 also, to yield 2048 x 1360 images. My higher quality Fuji S2 takes 6 megapixel images at 3024 x 2016. What this means is that if you shoot a consumer camera at the 3 x 4 ratio, you will need to crop your image in order to print it on a conventional paper size.

2) Pixels: This is the most important concept in this month’s column – In printing, Pixels are everything. The more pixels that come out of your camera, the better print you will be able to make. Pixels per inch, also called dots per inch (DPI), is the next most important concept – this denotes a digital image’s RESOLUTION. It’s a bit tricky, because computers display images onscreen at a resolution of 72 DPI. However, it takes 300 pixels per inch, or 300DPI to make a digital print that looks as good as a film print. That means that a file that comes out of the Fuji S2 at a size of ~3,000 x 2,000 can make a beautiful 10 x 6 2/3” print. At 4 x 6, that same file will yield a 4 x 6 print at over 500DPI.

3) File Format: Most cameras produce images in a format called JPEG, but others give the option to save images as TIFF or RAW files. Still more confusing is that there are different “qualities” of JPEG images. This leads to the next basic concept ->

4) Compression: JPEG files are compressed by computer software to remove “wasted space” in the file. That’s why you can choose three different qualities for your JPEGs – the highest quality has the least compression. TIFF and RAW files are not compressed. This is important because too much compression – while it will help fit more photos on your memory card – can lead to fuzziness or “blockiness” in your photos.

A JPEG from the Fuji S2 – this shot was taken at “fine” quality –
meaning the image was not highly compressed by the camera software.

5) Calibration: Many times I have printed a photo that looked great on my computer but came out too dark or too light, or even the wrong color! This is because what you see on your monitor screen is not always what you get – unless your computer and printer are not properly set up and calibrated. The way that this is done is to calibrate your monitor using a program called Adobe Gamma or better yet, using a device that reads a color chart and compares it to your monitor to be sure it’s showing true color and corrects it if it’s not. The next step is to make sure that the computer is sending the correct color information to the printer. Since each printer/ink/paper combination will show colors differently, something called a “profile” is used to set all of this information before a file is sent to the printer. Profiles are numerous and confusing, but fortunately, this concept has been explained rather well on websites such like DigitalFocus.

These five basic concepts will help you make a digital file that is suitable for printing. But after you have a file ready for press, how do you print it? There are two main ways to get good prints from your digital camera, you can buy a home photo printer, or you can take them in to a lab on your memory card or CD-ROM.

Printing at the Photolab: Surprisingly, the same Fuji Frontier that most labs use for making prints from negatives is the exact same printer that they use for making prints from digital files. Surprisingly, the photolab at Walmart is one of the best and least expensive places to make Fuji Frontier prints! Find out what paper you will use and save your image at the size you want, at a resolution of 300 DPI (the Frontier’s highest) and save it to memory card or CD-ROM. It’s best to also embed the Frontier’s profile into your image – the articles mentioned on Photo.net will explain how. Costs for printing at Walmart vary, but are always surprisingly low.

The Canon S900 – the telephone handset gives the scale

Printing at Home: Printing at home is affordable, and fun. A good photo printer that can do 8 ½ x 11 inch prints costs about $300 and one that can do 13 x 19 inch prints can be had for about $500.

This shot shows an assortment of Canon photo papers
and one of the ink cartridges for the S900

I use a Canon S900 letter sized printer. This wonderful machine can print a 4 x 6 in 10 seconds and an 8 x 10 in under a minute. The printer also uses 6 ink tanks, so if your blue runs out, you don’t have to replace the whole cartridge like in the past. Another new feature is that this unit can do edge-to-edge printing – also called “full bleed.” Epson makes a comparable printer at a more competitive price, but it is not as fast. When printing at home, the choice of paper and ink is very important. The paper you use will have as much impact on your results as the printer! The choice of ink will also have an impact on the durability of your prints. Some inks are designed to last 30 years without fading, while others are not. Name brand paper and inks cost about $11 per cartridge and $0.67 per page for professional paper. I use Canon paper and inks which are matched to my printer because I feel this gives the best results. For folks looking to save money, a little research and trial and error with generic papers and inks can also yield good results. I’m always amazed when I hand a friend a photo I printed at home on Kodak, Ilford, or Canon paper and ask them to compare it to a print from a lab – they can’t tell the difference!

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