To attach a document that is only available in hardcopy format, you must convert it into an electronic file by using a scanner and third-party scanning software.  Only portable document format (.pdf) files can be attached in the System.  Whenever possible, as in the case of CADD site maps, you should first determine if an electronic version of your document isn't already available in PDF format.

Scanned Document Quality vs. Attachment File Size

The key to creating a good attachment from a scanned document is to find the best balance between image quality and file size.  When an attachment becomes too large, the response time to view the document from a Web browser can degrade to very inefficient levels.  Likewise, if the caliber of an image is not clear or detailed enough it may be just as unusable.  Use a process of trial and error to determine the best formatting for each scanned document on a case by case basis.  Attempt to create the smallest file size possible without compromising image quality.

NOTE:  Keep attachment file sizes below 5 megabytes (less than 5,000 KB).

There are several factors that can universally help in the creation of high quality scanned images that are an appropriate size for reviewing over the Internet:

• Do not use color recognition unless absolutely necessary.

Scanning a black and white document as if it were color adds a lot of bytes to the file size without adding any value to the scanned image.  In fact, in some situations, some of the sharpness of black lettering is lost because they are no longer pure black but rather a combination of several colors.  In general, reserve color recognition for photographs, topographic maps, drawings with color annotations, etc.  The difference in quality, accuracy and file size when using grayscale vs. black & white recognition must be determined per your scanning software because it is not consistent across manufacturers.

• Limit the dimensions of each page to their true size.

Having extra "white space" along the length and/or width of a scanned document adds unnecessary overhead to the size of the resulting file.  A common mistake that can easily be overlooked is to scan an 8.5 x 11" document as if it were 8.5 x 14".  The blank area at the bottom of the image actually counts towards in the overall size of the file.

• Determine the lowest acceptable resolution.

The resolution or dots per inch (dpi) of an image is crucial to both its quality and size.  For example, doubling the resolution from 150 to 300 dpi might improve detail on your image but it can quadruple the resulting file size!  A resolution of 150 to 200 dpi seems to typically provide a good image that views and prints well and is accurate to the original document.

• Do not use Optical Character Recognition (OCR) in any situation!

Not only does OCR increase the file size of a scanned image, it can alter it!  OCR attempts to interpret every element that is being scanned as a recognizable word found in the dictionary of the software with which you are scanning.  For example, the last name "Smythe" may be changed to "Smith".  In essence, OCR is a great time saver that spares you from having to retype a document into a word processor.  But the image may no longer be true to the original and the resulting file size can be a lot larger.

• Break large multi-page documents into several files.

In general, it is better to keep a multi-page document as one file because it is a lot more user-friendly to the end-user than having to open each page as a separate file.  However, for very large documents, consider breaking them into two or more smaller scanned images.  For example, it may be better to create two files each with 30 pages than one large file with 60 pages.  Again, only you can make that determination at the point you save your scanned images to file.

• Use Adobe "Reduce File Size" feature if applicable.

Some versions of Adobe have a feature called "reduce file size".  This feature can be used to reduce the size of a PDF, and is recommended whenever possible to help minimize the size of PDF attachments.

NOTE: If you suspect that a PDF was created from a scan that involved high overhead settings for things like color recognition or OCR, you can realize a size savings just by re-distilling the file.  For example, the Central Office has been able to take a 9 megabyte PDF attachment down to 2 megabytes simply by printing the file back to a distiller print driver.  The second distill in essence got rid of the color recognition and OCR by treating the file as a plain black and white image.

To attach a document that is only available in hardcopy format, you must convert it into an electronic file by using a scanner and third-party scanning software.  Only portable document format (.pdf) files can be attached in the System.  Whenever possible, as in the case of CADD site maps, you should first determine if an electronic version of your document isn't already available in PDF format.

Scanned Document Quality vs. Attachment File Size

The key to creating a good attachment from a scanned document is to find the best balance between image quality and file size.  When an attachment becomes too large, the response time to view the document from a Web browser can degrade to very inefficient levels.  Likewise, if the caliber of an image is not clear or detailed enough it may be just as unusable.  Use a process of trial and error to determine the best formatting for each scanned document on a case by case basis.  Attempt to create the smallest file size possible without compromising image quality.

NOTE:  Keep attachment file sizes below 5 megabytes (less than 5,000 KB).

There are several factors that can universally help in the creation of high quality scanned images that are an appropriate size for reviewing over the Internet:

• Do not use color recognition unless absolutely necessary.

Scanning a black and white document as if it were color adds a lot of bytes to the file size without adding any value to the scanned image.  In fact, in some situations, some of the sharpness of black lettering is lost because they are no longer pure black but rather a combination of several colors.  In general, reserve color recognition for photographs, topographic maps, drawings with color annotations, etc.  The difference in quality, accuracy and file size when using grayscale vs. black & white recognition must be determined per your scanning software because it is not consistent across manufacturers.

• Limit the dimensions of each page to their true size.

Having extra "white space" along the length and/or width of a scanned document adds unnecessary overhead to the size of the resulting file.  A common mistake that can easily be overlooked is to scan an 8.5 x 11" document as if it were 8.5 x 14".  The blank area at the bottom of the image actually counts towards in the overall size of the file.

• Determine the lowest acceptable resolution.

The resolution or dots per inch (dpi) of an image is crucial to both its quality and size.  For example, doubling the resolution from 150 to 300 dpi might improve detail on your image but it can quadruple the resulting file size!  A resolution of 150 to 200 dpi seems to typically provide a good image that views and prints well and is accurate to the original document.

• Do not use Optical Character Recognition (OCR) in any situation!

Not only does OCR increase the file size of a scanned image, it can alter it!  OCR attempts to interpret every element that is being scanned as a recognizable word found in the dictionary of the software with which you are scanning.  For example, the last name "Smythe" may be changed to "Smith".  In essence, OCR is a great time saver that spares you from having to retype a document into a word processor.  But the image may no longer be true to the original and the resulting file size can be a lot larger.

• Break large multi-page documents into several files.

In general, it is better to keep a multi-page document as one file because it is a lot more user-friendly to the end-user than having to open each page as a separate file.  However, for very large documents, consider breaking them into two or more smaller scanned images.  For example, it may be better to create two files each with 30 pages than one large file with 60 pages.  Again, only you can make that determination at the point you save your scanned images to file.

• Use Adobe "Reduce File Size" feature if applicable.

Some versions of Adobe have a feature called "reduce file size".  This feature can be used to reduce the size of a PDF, and is recommended whenever possible to help minimize the size of PDF attachments.

NOTE: If you suspect that a PDF was created from a scan that involved high overhead settings for things like color recognition or OCR, you can realize a size savings just by re-distilling the file.  For example, the Central Office has been able to take a 9 megabyte PDF attachment down to 2 megabytes simply by printing the file back to a distiller print driver.  The second distill in essence got rid of the color recognition and OCR by treating the file as a plain black and white image.