Variable speed of scanning

[il barbi]

I'm puzzled about the behaviour of my Epson perfection 2400 Photo when
scanning slides, namely I set 4 slides at a time, run Epson Smart Panel in
manual mode,
start the preview, then
start scanning at 2400 dpi. Now for each slide the scanner waits some
seconds, then starts scanning with a variable speed for each slide. The
scanning time can vary from 1' to 3'!! I thought it was constant... This
happens with WindowsXP and moreover I see no difference of time between USB
1.1 and 2.0 (btw how can I be sure that USB 2.0 is working at full speed?)
On another PC with Windows98 and USB 1.1 the situation is somewhat stranger
because the performance is better (!) yet the time still varies from 50" to
1'30"... I don't understand. Is it possible that the PC with WindowsXP is
slowed by unnecessary processes? Anyway in my tests I have disabled all
antiviruses & firewalls. But the main problem is the variable time of
scanning
il barbi

 

[CSM1]

I'm puzzled about the behaviour of my Epson perfection 2400 Photo when
scanning slides, namely I set 4 slides at a time, run Epson Smart Panel in
manual mode,
start the preview, then
start scanning at 2400 dpi. Now for each slide the scanner waits some
seconds, then starts scanning with a variable speed for each slide. The
scanning time can vary from 1' to 3'!! I thought it was constant... This
happens with WindowsXP and moreover I see no difference of time between
USB
1.1 and 2.0 (btw how can I be sure that USB 2.0 is working at full speed?)
On another PC with Windows98 and USB 1.1 the situation is somewhat
stranger
because the performance is better (!) yet the time still varies from 50"
to
1'30"... I don't understand. Is it possible that the PC with WindowsXP is
slowed by unnecessary processes? Anyway in my tests I have disabled all
antiviruses & firewalls. But the main problem is the variable time of
scanning
il barbi

If you have auto expose for slides, the scanning speed will vary with the
density of the slide.
This is normal.

The difference between USB 1.1 and USB 2.0 is in the speed of the data
transfer, not in the speed of scan time. Scanners are slow in comparison to
the transfer of data.

 

[Winfried]

Scanners are slow in comparison to

the transfer of data.

Not quite right. For instance, I use a Canon FS4000US. This Scanner can
produce about 120MB of data within 48 seconds. This is too much for the
buildin USB1.1-Interface. (It is no problem with the buildin
SCSI-Interface)
You are correct in regard to USB2.0, Firewire or SCSI, but USB1.1 can
be slower than scanners.

Winfried