Color Graphics - Your copying, printing & specialty needs

Layout Tip - Scanning

Scanning: Many people have scanners of their own and scan pictures into their computers for layout purposes.  Different scanners have different capabilities and most are adequate for simple layout uses. However, if you are setting up a layout which is going to be a high quality brochure run on a printing press the pictures should be scanned in professionally. If you would like us to scan in your pictures for you please see our services under Graphics and Scanning .

Before you scan determine what you are going to be using the pictures for. Are you going to use them for printing out on your home color inkjet printer, are you sending them to us for high quality digital color or black and white copies, are they for internet purposes, do you want to have us blow up the picture on our large full color printer, etc.

High Resolution = Large File Sizes

Low Resolution = Small File Sizes

If you are going to use them on the internet, the resolution (dots per inch or dpi) should be low for quick transport across the web and if they are for posting on a web site they should be low resolution so the file is small and can be downloaded using a web browser quickly. 

In the case where you want to send a picture as an attachment to a friend across the internet, scan the picture at no more than 72 to 100dpi.  This will give you good enough resolution for viewing on the screen but the picture will still arrive on your friends computer without choking his or her system.

Once you have scanned in a picture at low resolution you CANNOT increase the resolution or the quality of the scan.

If you are scanning for posting on the internet, scan at no more than 72dpi and then save it in a .jpg or .gif format which automatically shrinks the picture’s file size.  Then use a .jpg and or .gif crunching program which further shrinks the file for you.  Now when you post it on your web page, those viewing it will not have to wait an eternity for your pictures to down load. Also, most programs which can manipulate scanned pictures will allow you to save them in various formats. Save your color pictures for the computer screen and for the internet as RGB (Red, Green, Blue) formatted pictures because that is how you view them on your screen.

So once you have scanned in your 72dpi file, select the RGB mode and then save it as a .jpg format file.

.jpg and .gif files are smaller size files for the internetr

.tif and .eps files are larger size files for printing out

If you are scanning for layouts and for use in printing out scan in at 200 to 300dpi.  300dpi is normally a safe resolution for getting good results.  However, for a frame of reference, if you scan a normal 8.5 inch x 11 inch page in full color at 300 dots per inch your are looking at somewhere around a 25 megabyte file. You cannot transport this file around on a 1.44meg floppy disk and unless you have a DSL or Cable connection on your computer you can’t send it across the internet.

Once you have scanned them in, save them in a .tif format which is the safest format for printing because there is no automatic compression of the file. You can use .jpg files but make sure when you save a .jpg for printing you save it at the highest compression available. Also, when you get ready to save, most programs will allow you to select the CMYK (Cyan, Magenta, Yellow, Black) mode which is how color printers, copiers and printing presses arrive at full color.

So once you have scanned in your file at 300dpi, select the CMYK mode and save as a .tif file. If you are printing pictures on a black and white printer select Grayscale before you save instead of RGB or CMYK.  This reduces your file size. If you are scanning something that is only line art and has no gray scale qualities to it, select the line art mode instead of RGB, CMYK, or Grayscale, this reduces your file size even further.

Color scanning creates the largest file sizes, gray scale is much less and simple black and white line art creates the smallest file size.

Remember that the dots per inch (dpi) you scan the file in at is not the only determining factor in the quality of the scan. Different scanners have varying capabilities and the optical resolution and the dMax (maximum density) effect the quality of the scan you get.

Optical Resolution is how much raw data the scanner can pick up. In other words how well the scanner is put together and how much raw data it can actually read. Many scanners show high Maximum Resolution figures but this is usually interpolated resolution - in other words the scanner scans at one actual resolution and then software makes it look better (supposedly).

The dMax is not as important if you are just scanning pictures but is extremely important if you are scanning 35mm slides or other transparencies. This dMax figure measures the density which your scanner can read and 35mm slides are very dense.

Keep in mind, if you have a crummy printer it does not matter how good your scan is.

If you are scanning a picture in for blowing up to a large size color poster scan at least at 300dpi.  It really depends on how small your picture is and how big you want it to be. Sometimes 400 even 600dpi is require to get a good large full color poster. A good rule of thumb is if you take a 4” x 6” picture, using a decent scanner, scan it in at 300dpi, you will get a good 24” x 36” poster.  Once you have scanned it, save it as a CMYK .tif or .jpg file because large format full color printers print out using CMYK.