Ricoh Di-C1 Manual page 269

Mixed Original-Length Mode
Width detection: Same as for normal mode
Length detection: Done for each sheet
As a result, scanning is slower if the user selects
mixed size mode
To detect length, the machine counts transport
motor pulses from registration-sensor-on until
registration-sensor-off
Slide 269
This explains what occurs if the user selects mixed original-length mode.
Normally, in mixed original-length mode, original length is detected as shown
below:
The width is detected with the same procedure that is used when all
originals are the same size.
The machine keeps an area in memory that is sufficient for an original
of the detected width and 432 mm length.
Printing is done after length detection, and only the part of the memory
that contains data up to the detected original length is printed.
But, if some functions are selected (for example, Auto Reduce/Enlarge), the
length must be detected before image scanning starts. Because of this, the
machine must measure the length before scanning.
It must also make sure that the originals are in the correct sequence
before scanning. Because of this, the 3 steps in the manual are done.
If the original is duplex, the original is inverted again after scanning the
first side. Then the second side is scanned, and the paper is fed out.
Why must the machine measure length first when we use Auto
Reduce/Enlarge, Centering, and other functions?
With these functions, the machine must know the length of the original
accurately.
For example, with centering, the image is centered on the copy paper.
This cannot be done if the machine does not know the length of the
original accurately.
Also, with Auto Reduce/Enlarge, the size of the original's image is
decreased to fit on the copy paper. This cannot be done if the machine
does not know the length of the original accurately.
D366 Service Manual, Detailed Section Descriptions,
Basic Operation, Mixed Original Size Mode
269
Di-C1 Training