Butterdezilion I’m scrambling like crazy to get a million things done. So if you or anybody else can double-check my understanding of this, it would be very helpful.
I will see what I can do
Butterdezilion Number substitutions happen on what machines? Do they happen on the default setting for the machine, or do you have to lower the quality and file size to get number substitutions? Did Xerox set up warnings for the user to know that substitutions could occur with those particular settings?
Yes, there were warnings but not always obvious. Xerox released a list of affected scanners
Butterdezilion What settings are required to create an automatic clipping mask that takes off the outer edges of the scanned document? What settings create multiple layers, and are the layers created reproducible each time, or are they seemingly random? For instance, you lay the paper on the bed of the scanner. Then you press scan 5 different times, one right after the other, changing nothing and not even opening the lid of the scanner. Do all 5 scans give you the same layers – a reproducible result you would expect from a machine carrying out exact algorithms in a controlled setting?
No, they do not repeat between scans even if you leave the document on the scanner. The layers are not random as the obvious ones repeat: Signature, date stamp(s). The algorithm is susceptible to minor variations in how a color is interpreted and once a difference happens, its effects can cascade across the object. The settings are the ‘default’ setting on the machine but they can be changed by the administrator I presume. In some instances, the Xerox actually created the same mysterious speckled images that so far had remained unexplained. It is actually a known issue. Good thing is that its effects remain mostly invisible to the human eye.
Butterdezilion If you save a scan on the 7655 without previewing it, is the saved file different than if you preview it on the 7655 before saving it? If you send the scan directly in an email is it in PDF format? If they open it on a PC will they be able to move around pieces of content? If they open it on a Mac will they?
Yes, they are very different. The Xerox created file has a lot of differences with the final document, most notably, the JBIG2 compression. Since Preview saves it to a lower PDF standard (1.3) it cannot create the same file. The resulting files however look extremely similar at the PDF object level. The ability to move around objects depends on the software. Illustrator does it both on Mac and Windows.
Butterdezilion If you import a digital file to the copier does the copier make layers out of a digital file as well, before printing it?
I am not sure if the copier supports this workflow. When printing, the computer creates a printing stream and typically does not send the document across the network. To a printer, there are just no layers. Remember that the foreground objects are just bitmasks that get printed on top of the background.