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Digital
Corner
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Digital
Imaging on a Shoestring |
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Digital and traditional photography are the same in this respect: you can make prints yourself or have a lab do it. But in the digital world, printing your own photographs is a lot easier because it doesn't require a darkroom, breathing chemical vapors or standing on your feet until they become numb. There
are a variety of digital printing processes available but I'm only
going to discuss the three that are most likely to be of interest
you. However, keeping in mind that we're operating on a shoestring,
only two of these are reasonably priced. |
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No
longer. Enter the Epson Stylus line of ink-jet printers a few years
ago that re-defined what this process could deliver. And since I recommend
that you use ink-jet printers, I'd like to acquaint you with how they
work and how to get the very best output from them.
If you will recall, we discussed resolution last time and how it affects print size. I gave you a simple table to use for choosing the best resolution from the five choices on a Photo CD depending on your needs...web use, small prints, or large ones. Now let's see how that translates into getting the finest possible print your ink-jet can deliver. While low resolution images are fine for the web when viewed on monitors, printing them on paper changes things drastically. You certainly can print a 640 by 480 pixel picture at the same size it appears on the screen (as an 8.8 by 6.6 inch MAC image or a 6.7 by 5 inch WIN image) but you may not be satisfied with the results. It depends on how fussy you are about picture quality. The picture might look fuzzy or have jagged edges -called pixelization- a phenomenon that occurs when low-resolution pictures are enlarged and there aren't enough pixels to recreate the range of color or detail in the original image. As a quick fix, you can tell your imaging program to interpolate the image, that is, add more pixels to make the image look smoother, but the results are not always satisfactory because the program must guess where to insert extra pixels, what color they should be, and so on. To get the image quality you want, it's often necessary to reduce the image size; this pushes the existing pixels into a tighter fit, resulting in higher overall resolution and a more pleasing picture. Right about now, though, you may be thinking: "My color ink-jet printer can give me all the resolution I need, because it can print at 720 dpi (dots per inch)? or even higher." Well, yes, but what that really means is that the printer is capable of squirting out a maximum of 720 dots of ink per inch. If you want to get acceptable image quality, about three of those ink dots are going to be needed to print each pixel of your picture. If you have a 640 by 480 pixel image whose size is 8.8 by 6.6 inches, each linear inch will contain 72 pixels (72 ppi) arrived at by dividing inches into pixels (640/8.8 and 480/6.6). At the three dots of ink needed to print each pixel, your printer will only spit out about 216 dots in a line for every inch of paper as its printhead travels across the page (three dots of ink needed to form each pixel multiplied by 72 pixels equals 216 dpi). Since you paid for 720 dpi and only got 216 dpi you might think a hefty refund is due. Not so fast. You can print that picture at 720 dpi if it is reduced in size so its pixels scrunch together and 240 of them are forced to line up in an inch of space. Then, with each pixel soaking up three dots of ink, your printer would be outputting its full potential of 720 dpi (sorry, no refund). In order to pack pixels in that tightly though, the original 8.8 by 6.6 inch image must be reduced in size to 2.6 by 2.0 inches, making it a great size to frame as a doll house painting, but not good for much else. However, take heart. The three dots of ink to one pixel ratio applies mainly to fairly critical work. In practice, with the same 640 by 480 pixel image, you can get very good photo output at 4.4 by 3.3 inches ?by pushing the pixels together to 144 ppi? and possibly even acceptable 8.8 by 6.6 inch prints at their screen resolution of 72 ppi. Of course, if you began with a higher resolution, say, 1536 by 1024 pixels, you would get excellent 7.6 by 5.1 inch photos at 200 ppi. And you could even get good 10.6 by 7.1 inch photos at 144 ppi provided that you weren't going to hold them right up to your nose to examine them, since viewing distance has a lot to do with what an image looks like. Outdoor billboard images are printed at only 18 dpi but they look great...from the right distance. If all of this sounds a bit confusing, just make a few test prints at various resolutions and see how they look. You'll quickly know what works and what doesn't. What's a bit more difficult to figure out is how many prints of a certain size you can expect from an ink cartridge. The answer to this question is akin to one that philosophers and theologians argued endlessly in the past: How many angels can fit on the head of a pin? The answer is...there is no answer! That's because pictures are not composed of equal amounts of cyan(C), magenta (M), yellow(Y), and black(K). Well designed ink-jet printers -such as the Epsons- have separate black cartridges which can be changed independently of the color cartridge because black ink tends to be used more. Very generally speaking, figure about 25 prints, 8 by 10 inches in size for the Epson StylusPhoto when it prints at 720 dpi. This brings the cost of each print to between $2.00-$2.50 including good quality paper. It is a bit high compared to an conventional print, but really a bargain when you consider that, with a bit of practice, you can knock out a perfect print every time. If you print at smaller sizes, you'll get more prints for the same amount of ink. I always made big 11 by 14 inch prints when I worked as a photojournalist, but now that I'm more into fine arts photography, I prefer smaller prints. I find that a 5 by 7 inch or 6 by 9 inch surrounded by a generous border makes a handsome-looking print and one that doesn't have to be held at arm's length to be appreciated. A friend of mine cuts a sheet of paper so he has one piece 4-1/2 by 8-1/2 inches for small prints (and tests) and another 6-1/2 by 8-1/2 inches which perfectly centers a 5 by 7 inch print in the middle of the paper with a 3/4 inch border all around. Unlike traditional photography where 8 by 10 inches is a standard, the U.S. digital paper standard is 8-1/2 by 11 inches, which gives you larger sizes to play with when it is divided. Speaking of paper, quality ink-jet papers are proliferating like rabbits, but I would suggest you try Kodak's Inkjet Photographic Quality Paper Photo Weight. It comes in a 50 sheet box at a cost of about 60 cents a sheet. Polaroid also makes a good paper...a bit warmer in tone, but, alas, you cannot write on the back of it with either ink or pencil as you can with Kodak's. Many times you'll want to make a note of what manipulations and effects you used so this is a more important feature than you might at first think. There's another type of printer on the market...the Alps MD-1000 and no, it's not made in Switzerland, it's Japanese. Using four separate typewriter-like ribbon cartridges, it lays down dry ink on almost any paper with excellent results. Unfortunately it has two drawbacks; it's slow and it shows faint pressure bands where the cartridges have come in contact with the paper. The banding not generally noticeable unless you move the print around so that light reflects off it at an angle, but they're there. As for its speed (or lack thereof), all the processing of the image is done in the computer prior to being printed and this slows things down. Once it gets underway, though, it zips along, laying down ink one color at a time and retracting the paper between colors. It's fascinating to watch and the registration is perfect. Alps has an inexpensive glossy paper that makes prints look photo-perfect and the inks are totally waterproof and will never smear. Each Alps cartridge is separate so when one runs out, the printer will patiently pause until you put in a new one and then resume printing without missing a pixel. Cartridges are cheap, too, about $6.00 each. But despite its virtues, the lack of speed and banding mitigate against it, and I would recommend you buy one of the Epson StylusPhoto printers which now can print up to 1440 dpi with six colors (adding light cyan and light magenta to the CMYK mix) for extraordinary photo realism. The two extra colors make for smoother color transitions and better flesh tones. StylusPhoto printers have several other advantages. They can print on different textured media, including canvas, and can also knock out a panoramic print up to 43.34 inches long. If you print on Epson's High Quality Glossy Paper (about $3.00 per sheet) the results can be breathtaking. But rest assured, they'll be outstanding enough on Kodak or Polaroid paper to satisfy you...or anyone else. Now what if you want to get some prints (or even transparencies) of your work done commercially? No problem. There are labs and service bureaus set up to perform these services along with almost any other you may require provided you send them a Zip (or Syquest) disk with your photo file on it. You can have prints done on a Kodak or Fuji professional dye-sub printer, huge posters printed on paper, canvas or vinyl on one of Encad's wide ink-jet printers, watercolor-type prints made on an Iris printer using different textured papers for beautiful effects, or even prints directly output on color copiers made by Ricoh, Minolta, or Xerox (stay away from Canon...banding problems, again). If you want slides or larger transparencies from your files, these can also be made and, provided they have high enough resolution to begin with, you will not be able to tell that they weren't camera originals. Finally, there's yet another interesting process...conventional RA-4 color prints that can be made directly from your digital files on a photo finishing machine designed specifically for that purpose. I´ll
be covering some of these processes in more detail in future columns,
along with information on color matching, archival inks, and other little-known
techniques that can transform your digital creations into unusual and
imaginative images. In the meantime, you're now set to give digital
imaging a try for little more than the cost of a new camera and a few
lenses. So go to it...and have fun! Printers: Epson StylusPhoto 700 ($280) http://www.epson.com/cgi-bin/Store/index.jsp This is
the just-released, updated model of the Epson StylusPhoto printer which
adds a higher resolution 1440 dpi printing mode. Because more ink is
used at 1440 dpi, you'll probably opt to do most of your printing at
720 dpi anyway...so if you can find an older StylusPhoto at a bargain
price it could be a very good deal. Epson StylusPhoto EX ($500) Similar
to the StylusPhoto 700, except that it can output larger images...up
to 11.46 by 43.34 inches. Fargo Primera Pro Elite ($1700) Ink-Jet Paper: Kodak Photographic Quality Paper Photo Weight ($28 for 50 sheets) http://www.kodak.com/country/US/en/digital/genInfo/inkjet1.shtml#Photographic Polaroid Ink-Jet Photo Paper ($8 for 15 sheets) RA-4 Prints From Digital Files: Sienna Imaging, Inc., 303.754.2270 (Ask for a list of labs in the U.S. and Mexico) Equipment Sources: Mac or PC Connection (800.800.2222) http://www.macconnection.com
or Mac or Micro Warehouse (800.990.0736)
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