Who needs a 4800 dpi flatbed scanner ? (Solved)

[Kiriakos GR]

The people who have best background knowledge about printing and scanning images are the ones whom become digital photographers at 2003 and later. 
But not everyone ...   

Image scanning and image correction due Adobe Photoshop this is something special.
The software always sold for a serious amount of money.
You were forced to develop skills of using Photoshop tool box
And or to master at least the basics,  so to be able to remove unwanted content from a good quality digital photograph.

About flatbed scanners, the most demanding task, this is very old printed photograph restoration.
The quality of the scanner along it higher in dpi resolution, this were helping to bring more pixels inside the software editor, especially when the printed photograph (original) this were severely damaged.
Severely damaged analog photograph = discoloration and or parts missing, and or critical information of human faces this must be restored. 

The user of the software, he needed all the help in the world so to:
Scan
Crop
Edit the new digital image
And or magnify

In one attempt so him to repair of what time and or other parameters had cause damage at the specific photograph.
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Regular scan of undamaged photographs this will not require any extreme scanning resolution.

A third occasion that a high resolution scanner might do the trick,  this is when scanning a common in size old photograph, because you plan to print it at a much larger paper in dimension.

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Regular digitizing of documents and or receipts, this does not require any high dpi either.

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In conclusion, what we do buy when selecting a 4800dpi scanner instead of a 1200dpi, this is something that called as Additional Potential so to be used only at very special conditions = image restoration.

Industry will not aloud you to scan and print your own money     
This is why you can only use the full power of your scanner at smaller items than a printed 20 EURO bill. 

At electronics repairs,  you may take advantage of 80s printed electronic schematic, so you to be able to see finer details of the circuit / passive electronics parts/ individual component replacement value.

Modern flatbed scanners at 4800dpi they are a powerful magnifying glass for the ones who can actually use such potentials.
Vast majority of talented at using Adobe Photoshop, these will aim for a 4800dpi scanner even for hobby use.
As they will benefit from digital noise reduction, because the scanner sensor this will do a much better work.

[Kiriakos GR]

Thanks to this incoming feedback from a friend in Italy.

Today we know that at 4800dpi and at Twain allowed in dimensions scan, the scanner it will be forced to move data of 1.61GB  due the USB connection.

USB 2.0 = 53~60 MB per second  =  26.8 seconds for transfer delay
USB 3.0 =  300 ~ 400 per second =  4.02 seconds for transfer delay

But here we have and even more feedback,  the scanner table in order to collect the data,  this required five minutes at a USB 2.0 capable scanner.
10 years old scanner production, this can scan 600dpi in 10 seconds.
Newer hardware production can do 8 seconds at 600 dpi.

The math proves 20% faster processing power (CPU related) VS the old.

So the latest 4800 dpi hardware will require 20% less time of the five minutes,  so to finish the scan.
Five minutes = 300 seconds
New expected performance delivery this is approximately calculated at 240 seconds = 60 seconds faster.

And so here we have the final math at 4800 dpi.
Technology of  2012  = 5 minutes
Technology of  2020  = 4 minutes

And now I will be fully explain my motives, I did start a debate in me,  if a used 4800dpi scanner, at half the price of the newer 4800 dpi, this is a good investment?
But this is ITTSB Blog and I am expert in electronics, unfortunately at used scanner you are unable to know or measure (CIS) scanner head degradation.
(CIS) scanner head degradation this translates to a softer in detail of a scanned image.

CIS = contact image sensor (LED)
   
Software tools of sharpness they can not compensate the missed detail due the age of the sensor.
If the used scanner seen little of use ?  Then the sensor it might be in good condition.

There is no any easy answer here,  but if you plan to sale the result of your scan to a customer, buying the latest scanner this seems right to me.
For home - office applications, the used scanner it might be still an option. 

Facts learned today:
Scanner sensor this is much more slower than any benefits has to offer USB 3.0 in favor of data bandwidth.
Scanner glass transparency this is another parameter to worry about, used glass might be has scratches due poor cleaning at removing dust.
Very few will had use a soft microfiber cloth at the entire time that they had use their scanner. 
 
For max sanity, you must be able to test the used scanner before paying for it.
If you do not wish doubts to swim in your head then buy a new.