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Most print buyers don"t think twice about who will scan their color photography or what kind of scanning equipment will be used. The demand for color accuracy, fine detail and resolution make a print shop's drum scanner the only logical choice for color printing. But when the photos are black and white, we printers often hear challenges to the print shop's handling of halftone scans.
Q: "I save money when I scan photos. Why involve the print shop?"
A: Yes, you save money. But, when your image is on the line, do you want to take a chance on quality to save a few dollars? You"ve invested time, money, and the effort needed to produce a good photograph. Don"t stop there. Think about your audience as you decide. Are you mailing to a hot prospect, the final decision-maker, or a current client who will bring repeat business and referrals?
Check out the side-by-side scans shown in this portion of our website. They show you exactly what you get with flatbed-scanned photography vs. drum-scanned photography. The quality of the photography used in your marketing materials helps build you (or your client's) image. Do you really want to take that chance?
Q: "I have an in-house scanner and my boss expects me to use it. What do I tell him/her?"
A: Tell the truth: that you are using your in-house scanner for what it should be used for-line art scans and photographic position prints. Line art is any image that does not have a shaded or grayscale quality. Black and white logos, pen and ink drawings and schematics are all examples of line art. Photographic position prints are photo scans that are "place-holders" that will eventually be replaced with higher quality scans. Position print scans are perfect for the mock-ups or comprehensive proofs you will be showing the boss. They are also helpful in communicating exact photo sizing and cropping instructions to the printer. When you are ready for final, high-resolution scans, turn the document and photos over to the printer for durm scanning and position print replacement.
Q: "What do I do when I want to use Photoshop to clean up and manipulate photographs?"
A: We know how practical (and fun) it is to use Photoshop., So let us give you an excellent quality, original, high-resolution scan to modify. Take a moment to crop and size the photographs and turn them over to us. We will scan and return high-resolution images that you can manipulate to your heart's content. (All you need to tell us is how much to reduce or enlarge the original.) After the document is completed, we will import your retouched scan through the automatic picture replacement process. You get the best of both worlds - high quality scans and personal retouching action.
Q: "It looks goo don my monitor - what's missing?"
A: Monitors show images at a resolution of 72 dpi using RGB color. At that low a resolution, anything will look good. Don"t be fooled by your monitor - make sure your resolution is within the acceptable range for commercial printing. Rule of thumb: a final printed image requires a minimum resolution of 2400 dpi. This means your input resolution must be a minimumn of 300 dpi.
Q: "I need position prints for my client anyway - so why not use the same scans in the final document?"
A: See answer No. 2 (for the boss). Use your scans for position prints - but please - let the print shop do the quality scanning in the end.
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Q: "It looks good on my monitor - what's missing?"
A: Monitors show images at a resolution of 72 dpi using RGB color. At that low a resolution, anything will look good. Don"t be fooled by your monitor - make sure your resolution is within the acceptable range for commercial printing. Rule of thumb: a final printed image requires a minimum resolution of 2400 dpi. This means your input resolution must be a minimumn of 300 dpi.
Q: "I need position prints for my client anyway - so why not use the same scans in the final document?"
A: See answer No. 2 (for the boss). Use your scans for position prints - but please - let the print shop do the quality scanning in the end.
Q: "It's just a one-color job. Why should I bother?"
A: The one-color job should get the same respect as the four-color job. Many times, one one-color job has just as significant a message as the fancier color piece.
Q: "Isn"t it faster if I do my own scans?"
A: Scanning takes little time in the whole scheme of the job. We may be scanning your original photos while you are tweaking the final corrections of the document. The result is no time lost on print shop-scanned halftones.
Q: "I use flatbed scans for internal pieces. Why not use them for everything?"
A: Use flat-bed scans for position prints, internal publications, website updates and any other non-external item you can find. But use drum-scanning services on your image pieces - for all the reasons explained above.
WHY DRUM SCANNERS EXCEL
As a rule, you can assume that a drum scanner contains PMTs and a flatbed scanner is based on photomultiplier tube (PMT) technology and produces the best quality reproduction because it has a complete dynamic range. Tonal and spatial resolutions relate to the amount of date that can be captured by a scanner over a fixed space. The more data (color or gray information) that is captured, the more resolution will be retained and ultimately reproduced. In printing reproduction, the most critical image benchmark is resolution.
With a drum scanner, the oringal is attached to a drum that spins while a moving, laser recording head reads the color or gray values of the original. The photomultiplier itself is a vacuum tube. The reflected light from the image hits the tube and is converted into electricity. This electrical signal is strengthened (i.e. multiplied), and the strengthened signal is what is converted to digital form. This multiplication feature is the reason PMT scanners are able to capture a larger density range than CCD scanners.
Offices usually have moderately priced flatbed scanners. These are charge-coupled device (CCD) scanners that have a fixed number of sensors arranged on a computer chip called a "CCD array." Fixed sensors allow only a certain amount of pixel information to be gathered, regardless of the original's size. This limitation generally results in a lower quality reproduction - becoming especially apparent when images are enlarged.
CCD scanners have a flat bed, usually glass, on which the original is placed. Upon scanning, the bed is moved past the CCD array, where the image is captured and converted to digital form. The shorter dynamic range and limited resolution inherent in CCD technology are what lead to negative effects such as darkening, halos, banding and pinholes.
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