Epson 4990 4x5 Digital Ice Restarts with Warmup Message

[alanmcf_ng]

I was trying out a friends new 4990 before buying one for myself. My
first 2400 dpi 48 bit scan of a 4x5 was quite fast. I then turned on
Digital Ice and it got very slow. That would not be so bad, except
about 30% into the transparency it stopped, repositioned to the
beginning, gave the "warming up" message, repositioned, and continued
the scan. Is this normal behavior? To my way of thinking it could not
possibly reposition properly. I have owned at 1200u, 1640 and now a
3200... and if overtaxed they would just stop and wait a bit, but they
would not totally restart with a warmup. BTW this was with the Epson
Twain, not SilverFast or Vuescan.

Thanks for any help, Alan

 

[rafe b]

I was trying out a friends new 4990 before buying one for myself. My
first 2400 dpi 48 bit scan of a 4x5 was quite fast. I then turned on
Digital Ice and it got very slow. That would not be so bad, except
about 30% into the transparency it stopped, repositioned to the
beginning, gave the "warming up" message, repositioned, and continued
the scan. Is this normal behavior? To my way of thinking it could not
possibly reposition properly. I have owned at 1200u, 1640 and now a
3200... and if overtaxed they would just stop and wait a bit, but they
would not totally restart with a warmup. BTW this was with the Epson
Twain, not SilverFast or Vuescan.

Yes, believe it or not, this is normal behavior.

The first couple of times I saw it, I was sure
something had gone terribly wrong.

It takes a looong time to scan 4x5 @ 2400 with
dICE turned on. So be patient. There will be
several minutes of processing even after the
scan is complete.


rafe b
www.terrapinphoto.com

 

[alanmcf_ng]

Are you really saying the CCDs go back to the beginning, recalibrate
via a warmup, and then reposition to where it left off without loosing
registration and screwing it up. Tell me again it is or it isn't so.
Alan

 

[rafe b]

Are you really saying the CCDs go back to the beginning, recalibrate
via a warmup, and then reposition to where it left off without loosing
registration and screwing it up. Tell me again it is or it isn't so.

I'm telling you that's exactly what happens.

Trust me, it really works. But it takes a long
time, so be patient.

It would have been nice if Epson said something
about this in the manual. I'm sure lots of
4990 owners have the same "WTF?" reaction.


rafe b
www.terrapinphoto.com

 

[alanmcf_ng]

My last post has not been googled yet, but I now think because of some
reading that I understand a bit better. The second scan would be the
infared digital ice scan. The fact that it does not make it all the way
through the first scan in one pass, may be because there is not enough
PC memory. I do wonder if VueScan or SilverFast and/or Firewire would
help. Thanks again Rafe... your posts helped a lot.

Alan

 

[false_dmitrii]

My last post has not been googled yet, but I now think because of some
reading that I understand a bit better. The second scan would be the
infared digital ice scan. The fact that it does not make it all the way
through the first scan in one pass, may be because there is not enough
PC memory. I do wonder if VueScan or SilverFast and/or Firewire would
help. Thanks again Rafe... your posts helped a lot.

Yes, the scanner has to do a separate warmup on the infrared light when
it gets to ICE. And that's as far as my knowledge goes.

If you're concerned about the scans lining up, try Vuescan and scan a
64bit RGBI image. Then you can compare the "I" channel (alpha channel
data, I believe) to the uncorrected defects to see whether they match.

false_dmitrii