When I charge a school by the byte, this is how it's done.                    
I will continue using the two sample images.                      
I scan all the pages, not just the images, at grayscale, 150 dpi (dots per inch), letter size, orientation as portrait, at a brightness level of 100% and a contrast level at 100%. To ensure consistency these parameters are never changed. Why those? I need at least those so I can copy and paste text. Any lighter or less dpi, I would not be able to do that.                     
I open the file that the teacher sends to me. It could be in any format such as a PDF, a Word document, a PowerPoint file, an OpenOffice file, etc.                     
I then print the original document on an HP 2420 Laser Jet printer so I can scan those newly printed pages.                     
Just for this pricing tutorial I made 3 separate scans just to show you that the resulting PDF had about the same number of bytes from the printouts of different programs, but only after I scanned the original printouts. The biggest spread in this example of the number of bytes shown is 1,450 bytes, which comes out to 35 cents. At a per-byte charge of $0.00024, it doesn't matter much that the total is off by a couple of thousand bytes. (1,000 bytes of a graphic cost 24 cents.)                      
These are the results of those scans: $0.00024 <-- price per byte.                  
Rescan of Original in Word's PDF the size in bytes is: 40,021 bytes $9.61                  
Rescan of Original in WordPerfect's PDF the size in bytes is: 38,715 bytes $9.29                  
Rescan of Original that the teacher sent to us: 38,571 bytes $9.26                  
As you can see, the price difference between scans is low.                     
As I said, whatever is given to me I first print the pages on an HP 2420 Laser Jet printer . It does not matter what the format is. Almost always I receive PDFs, but sometimes Microsoft Word files too. It could also be PowerPoint files, spreadsheet files, other PDFs, etc. It doesn't matter.                   
We are almost at the end so please just continue for another minute…                    
Let's compare the image that needs a lot of work with the image that needs no work. This is the main reason why I created this pricing tutorial.                  
It takes far more effort to clean up a graphic that has a lot of stuff in it than it does to just copy and paste an image. Do you agree with that? I hope so.                  
Why do I have to clean up an image? Because about 999 out of 1,000 of them are printed in black ink and black is what is picked up to form the tactile image. Colors are not picked up. If I did not clean up the image below, the letters and shading would be in the tactile graphic. (The letters are made into Braille labels. Our samples show you what that looks like.) Sometimes shading is needed, especially in maps and graphs, but not in the case of the image below. By the way, our shading comes out as felt or shaggy loops. It's amazing!                  
Click here to see samples.
  Image that needs a lot of work: Image that needs no work:                    
  40,021 32,703                      
  $0.00024 $0.00024                      
  $9.61 $7.85                      
$9.61 … is the price to complete the image that needs work.                    
$7.85 … is the price to complete the image that needs no work.                    
This way schools are not overcharged and we don't lose money.                    
           Text prices:                    
What about text or a combination of text and graphics on the same page?                  
When there is text with an image then there is no additional charge.                   
When there is text with and there is no image on the page that you want us to do, as long as it can be scanned, copied and pasted into our program (almost all can be), the charge is $0.001 per byte. For example, this line of text would cost $0.37 to transcribe and emboss and mailed as Free Matter to you because it has 369 bytes letters, spaces, and punctuation marks.                
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