When considering which scanner to purchase or rent for a project, customers must consider two primary types of large format scanning technologies: CIS (Contact Image Sensor) or CCD (Charged Coupled Device). Each have the same basic elements—including one or more image sensors and a light source. In the early days of CIS, there was a major difference in image quality and color fidelity; but like any technology, as new iterations of CIS were developed, those differences have become less apparent. However, each technology does have its own benefits—and which one to choose depends greatly on the application and what the images will be used for.

Similarities

Almost all models of CIS and CCD scanners share these attributes:

Scan Width: 24″, 36″, 42/44/48″, 60″
Color Capture: 48-bit color, 16-bit grayscale 
Scanner Output: 24-bit color, 8-bit grayscale 
Optical Resolution: 600 or 1200 dpi (most applications only need up to 600 dpi) 
Scan Speed: Very fast (but not important, as you can only load a scanner so fast!) 
Output Formats: Standard (Multipage PDF (PDF/A) and TIFF, JPEG, JPEG 2000, PNM, PNG, BMP, TIFF) 
Light Source: Two lamps with white LEDs 

Differences

How the two technologies differ will determine which is the best fit for what you want to accomplish. CCD is the older of the two technologies, but is still the most capable: 

Depth of Field: CCD scanners will maintain focus for up to ~3/8”.  This will be a benefit for folded documents and more importantly, originals with any texture. If you are trying to pick up the exact look and feel for archival purposes or you are scanning art with any texture, you will want CCD. CIS scanners focus right on the glass, so are best used for line drawing applications. 

Color Gamut: CCD has traditionally had a much larger and more accurate color gamut. However, the CIS technology has been getting better and better over the years. If you are in an archive or art-related field, we still recommend a CCD scanner. 

Cost: CCD scanners are more expensive because they use a camera lense type of technology for data capture. CIS scanners use an electronic sensor that sits underneath the glass and is less expensive. Because the CCD technology incurs more cost—but is more capable—the manufacturers have also devoted more design and development to paper handling, so you also end up with a more robust scanner. 

Which Technology is Best?

This question is somewhat dependent upon the application that the scanner is being used for. A good way to make this determination is whether you need to capture color at a high resolution and with a wide and highly accurate color gamut. If so, then a CCD scanner is best for you. If you primarily scan line drawings, blueprints, or any other document that does not require high-end graphics resolution, then you may want to consider a CIS scanner. CIS scanners are not only less expensive, but also require less calibration and are very effective and accurate machines for most scanning applications.

Need help? We represent all of the possible solutions for large format scanners and are not tied to any one manufacturer. We gather all of the requirements and will recommend several possible options and tell you why. We have been in business for over 22 years and have been in the industry for 20 more years, dating back to when digital scanners first came on the market. Please let us know if we can help you find the scanner that is right for you!