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By Dan Keegan
As a service bureau (sign shop, digital printer, offset printer, screen printer, etc...) you are often faced with projects that require the use of photographic images. These images may come from a variety of sources, some good and some bad. The Internet is a great tool for all, but due to the fact that people place photographic images in the web pages, the end user often thinks that those images are useable in printed form. Some are and some are not. How often has a client walked into your door with a business card, letterhead, a page of a book or magazine, or even a photo that has been in a wallet for 10 years to use as artwork? A client may not have anything and request that you create what is needed. The old saying, “garbage in, garbage out” holds true in many cases. There is only so much that you can do!
Those clients with the business cards are most often looking to re-create the corporate identity (logo & name) in another format (print or die-cut vinyl) that is to be used on a sign or ad. Some you will be able to use the eyeball method to create the logo and match the font style. While those with complex logos or the photograph require that some form of input device be used to go from point “A” to point “B” (otherwise known as your computer system). The two most common forms of digital input are the digital camera and the scanner.
Technology of the digital camera has come a long way in the past couple of years. The most common digital cameras that we see in the price range of $200.00 to $350.00 are ideal for viewing images on the screen, but not so great for printing proofs or for the final product. The main reason for this is that the resolution of the low-end digital camera is 1024 x 768 or below. Low resolution means that you cannot pick up that fine detail in the image and the features of the camera are somewhat limited.
1. What is the maximum or highest resolution of the camera?
Resolution is the key to choosing the right digital camera. If the camera has the ability to take a picture at a resolution of 1600 x 1200, then there is enough information in the image to enlarge, print and manipulate the image. Keep in mind that the purpose of having the camera is to be able to produce a printed proof to sell an idea to a client, to archive/print an image or to archive/print an image of a finished project. In order to do this you need the higher resolution to capture the fine detail.
Several low-end digital cameras utilize a 3.5" floppy disk, which is fine for low-resolution images. Floppy disks are inexpensive and have a storage capacity of 1.44MB, so you may have to take a ten pack of disks along with you to the photo shoot. Another disadvantage to the floppy disk camera is that the batteries drain faster due to the floppy disk drive motor in the camera.
Probably one of the best methods of storage is the “Smart Card”, which is no more than a removable memory chip about the size of a quarter. The “Smart Card” comes in several capacities that range from 4MB to 64MB and can easily be changed in the camera.
Avoid digital cameras that do not have some type of removable storage media!
3. How are the images downloaded into the computer?
The most common methods are through the use of floppy disks, serial cables, parallel cables and USB cables. Of the above, the USB cable has the quickest download time. Almost all computers built within the past two years have a USB port, but check your computer first before purchasing a digital camera to make sure that there is an available port. Some digital cameras will provide the user with at least two cable options to download images.
A new device called the “Smart Card Reader” is available and costs around $100. This device can remain connected to the computer at all times. Rather than connecting the camera to the computer, the user can remove the Smart Card from the camera and place it into the reader for downloading into the computer. This saves download time, wear and tear on the camera and battery consumption.
4. Does the camera have a zoom or close-up feature?
Both the zoom and close-up features are handy. The zoom feature will allow the user to remain stationary and get a close-up shot. In most digital cameras the zoom feature ranges from 2.5X to 10X. The 2.5X is sufficient in most cases. However, with the zoom feature you sacrifice resolution of the image. The digital camera will generally drop down one notch in resolution when the zoom is used. For example, if the setting were 1600 x 1200 it would drop to 800 x 600 using the zoom. Remember that you can always move closer to the object to get a higher resolution image.
The close-up feature is probably more important than the zoom. In close-up mode, the user can take a high-resolution image at distances less than two feet away without a drop in resolution.
5. What file format are the images saved in?
Virtually all digital cameras save the images in a JPEG (*.jpg) format, which is a highly compressed bitmapped image. A JPEG image has a compression ratio that can range from 20:1 to 100:1. In simple terms, an image that is 200KB can decompress to an image that is 2MB or greater. Avoid digital cameras that use custom or priority formats. Ninety percent of the now available software on the market can import a JPEG file. All digital cameras come packaged with some form of download and image viewing software. If the software package that you are using does not have the ability to import the JPEG file format, the packaged software will usually allow the user to save the file in another format such as a TIFF (*.tif) or BMP (*.bmp).
Because the digital camera is an electronic device, it is recommended that the user purchase the camera from a retail outlet versus a mail order house. It is recommended that you also purchase an extended warranty (cost: $50 - $60) for a two to four year period. When the extended warranty is purchased a reputable retail outlet can provide a quick repair turn-a-round time or provide a “Hot Swap”, which allows you to get a new camera immediately. Most manufacturers warranties range from 90 days to one year in which you will have to send the camera to them for repair, which could take 30 to 90 days.
Grades of digital cameras:
Professional grade digital cameras range in price from $20,000 to $150,000 which are stationary (not portable) cameras that remain connected directly to a computer system due to the size of file created (100MB +) at resolutions of 6000 x 4000 and greater.
A sign shop may need to install a new sign on the front of a building. Generally, a low-end digital camera can be used to snap off an image of the building frontage and then download it into the computer system. The proposed sign can then be placed into the digital photo at its approximate location and size. Next, the sign shop prints an 8.5" x 11" proof on the desktop printer for client approval. Once the client has approved the layout the same image may be needed for the local government agency approval. The printed image may not be of photographic quality, but it gets the point across.
The need may arise to where the medium to high-grade digital camera is needed to create images that show a finished product with detail. Whether they are to be printed in a brochure, used on a web page or used to create a computer based slide show, the higher resolution capabilities are needed.
What happens when your client, the construction company, walks in the door with a 19" x 35" hand drawn color architectural rendering and wants to reproduce this image in a much larger scale for a construction site sign? You go see your photographer buddy that has the professional grade digital camera.
The scanning equipment is by far a key factor in getting good scanning results. Your scanner needs to be flexible to your needs and of course you will pay the price for the flexibility. You may not need to have the capability to scan transparencies or slides which will help cut some cost. Most of the flatbed (desktop) scanners on the market will scan at resolutions between 3600 dpi and 9600 dpi, but be careful! These resolutions are what are known as interpreted resolution, which means that once you exceed the scanners true resolution the scanning software uses a mathematical calculation to achieve the higher resolutions. True resolution (also known as optical resolution) is what the scanner can perform without the assistance of software. Before purchasing a scanner read its specifications closely. The low-end scanners usually have an optical resolution of 300 dpi x 300 dpi. The midrange scanners range between 600 dpi x 800 dpi to 600 dpi x 1200 dpi. While the higher end scanners range between 800 dpi x 1200 dpi to 1200 dpi x 2000 dpi.
If you were not aware of the fact that there are two types of scanners in the past, you will shortly. The most common type of scanner is the desktop or flatbed scanner and the other is a much higher end drum scanner, which is used most generally by large reproduction houses. The flatbed scanner uses the CCD (Charged Coupled Device) method for scanning, while the drum scanner uses the PMT (Photo-Multiplier Tubes) method of scanning an image.
The drum scanner has a very high optical resolution, about 3 to 10 times that of the best flatbed, and can capture a higher range of tone depth. The drum scanner is best suited for scanning transparencies, film positives and film negatives. However, the starting price for a drum scanner starts at around $15,000 and can be as high as $150,000, which makes it difficult for the average person to own. For the most part a good flatbed scanner will provide everything that is needed in a scanner and if you need the services of a drum scanner there is a nominal fee to have someone else scan the image for you.
In reality, there is more to just purchasing any scanner. First, you will need to determine what your scanning needs are. Do you just need a scanner to be able to trace or convert artwork? Do you need to scan photos, slides or transparencies for digital output? What resolutions will I need to scan at? The following items, listed in order of importance, should be the questions that need to be answered:
1. How does the scanner connect to my computer?
The three common types of connections are parallel, USB, SCSI. Your computer typically comes equipped with a parallel port and one to two USB ports. A scanner that connects via the parallel port is usually less expensive than the other two types of connections, but you pay the price in speed and headaches especially when a desktop printer is daisy-chained to the scanner. The USB type connector is now the most common. When a SCSI connector is involved, an add-on SCSI controller card will need to be purchased and installed in the computer. SCSI connectors can handle data between the scanner and computer much faster than the other types of connectors. The higher end scanners are generally SCSI based. Some of the mid-range scanners include both SCSI and USB connectors. Inspect your computer for its connector before purchasing the scanner.
2. What is the TRUE optical resolution of the scanner?
As stated above, the optical resolution of the scanner is a key component to getting the best results. If you plan on performing enlargements and want better results, the need for higher optical resolution is much greater than just converting images to vector format or scanning text.
3. Is the software interface user friendly and flexible?
The scanner is just another piece of hardware without the software (user interface). Does the software have automatic settings? Commonly the answer is “YES”. The automatic settings are great if you need a quick and dirty printout from a desktop printer, but to be able to get those professional scans you may need to override the automatic feature. How difficult is it to do so? Each scanner manufacturer packages software with the scanner, some are better than others and provide more features. When possible, ask for a demonstration or talk to someone that has used the software. It may be a great scanner, but if the software interface stinks, what good is it?
4. What options come packaged or can be added to the scanner?
Does the scanner come packaged with a transparency scanner? Can a transparency scanner or document feeder be added at a later date? You may or may not need these options, but its nice to know if they are available and at what cost. One important feature is a changeable light source or the light bulb. This feature is generally found only in the higher end scanners. Why? Because over a period of time the light bulb will weaken, which means that your scans are not as accurate.
5. How much does it cost?
If you paid less than $200 for the scanner, consider it disposable after one year. You probably got your moneys worth out of it. Granted that most scanners will last more than a year. When the investment becomes much higher, those scanner options play a big part, especially the bulb replacement. No mater what, it all boils down to your needs.
Note: Also check the software that you use for scanner recommendations.
Keep in mind that a scanner can detect more than the human eye can. It is like looking through a high powered magnifying glass at a photograph. It can detect every scratch, finger print, paper texture and speck of dust on a photograph. To get the best possible scanned image from a flatbed scanner you might want to use a glossy photograph. Why? Because a glossy photograph has a very smooth surface and with a smooth surface the edges of objects in the photograph will be much sharper or more defined.
Dan Keegan is the author of Digital Imaging: Volume 1
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