Epson 4990 firewire problem

[Guido Haase]

Hello everybody,

in March 2005 I bought an Epson Perfection 4990 Photo. So far I'm very
happy about this deal because it's a relatively sheep method to scan
my 6x6 transparencies and negatives.

I few weeks ago I decided to buy a Firewire/USB 2.0 High Speed-Combo
card to increase the scan time, i.e. to speed up the data transfer
rate.

Well, with the USB 2.0 High Speed interface it increases a little bit.
But, the theoretical speed of a high speed USB 2.0 interface (480 Mbps
or 60 MBps) won't be reached approximately.

Scanning a 6x6 negative or slide with 48 bit color in 2400 dpi will
give a filesize of nearly 160 MB and takes nearly 90 seconds. This
corresponds to a transfer rate of 1.8 MBps or 14.4 Mbps, far away from
60 MBps (480 Mbps) of highspeed USB 2.0. I seems to be more close to
USB 2.0 "standard" speed of 1.5 MBps (12 Mbps).

Actually I'd like to use the Firewire (IEEE 1394) Interface. And
although I removed the epson software and any related entries from
XP's registry, installed it new and tried to used the firewire
interface, it doesn't work.

In detail this means, the scanner itself is recognized already, but if
try to scan anything, the EPSON software "hangs". After a while, the
software reports the scanner isn't responding. Trying Epson's last
version of EPSON Scan (Ver. 2.65) doesn't fix the problem. The combo
card is based on an ALI-Chipset.

If I do the same using USB 2.0 highspeed interface all works well but
relatively slow, see above.

Any ideas what's going wrong?

What scanspeeds do you reach under similar conditions (colors /
resolution / XP based systems)?

Thanks and by for now

Guido

 

[-]

Scanning a 6x6 negative or slide with 48 bit color in 2400 dpi will

give a filesize of nearly 160 MB and takes nearly 90 seconds. This
corresponds to a transfer rate of 1.8 MBps or 14.4 Mbps, far away from
60 MBps (480 Mbps) of highspeed USB 2.0. I seems to be more close to
USB 2.0 "standard" speed of 1.5 MBps (12 Mbps).

While those are the quoted speeds for the two transfer methods, the real
question is how fast the scanner can actually feed the data out. I think
that might be a limiting factor. Also, when you scan the whole process
involves more than just transferring data, so I am not sure that dividing by
the total scanning time is the best measure. This is especially true if you
have turned on options like ICE, grain reduction, sharpening, etc.

Doug

 

[Guido Haase]

Hi Doug,

thanks a lot for your reply!

While those are the quoted speeds for the two transfer methods, the real
question is how fast the scanner can actually feed the data out. I think
that might be a limiting factor. Also, when you scan the whole process
involves more than just transferring data, so I am not sure that dividing by
the total scanning time is the best measure. This is especially true if you
have turned on options like ICE, grain reduction, sharpening, etc.

Well, I'm only scanning without any hw- or sw-modifications and using
only resolution modes which are even parts of 4800 (because scanning
unit has exactly 4800 ccds, i.e. the maximal physical resolution is
4800 pixel).

So I do my testscans with exat 2400 pixel - hoping no extra- or
interpolation has to be done.

And, I'd like to know, which data rates other user get with this
device under comparable cirumstances.

 

[Ken Weitzel]

Hello everybody,

in March 2005 I bought an Epson Perfection 4990 Photo. So far I'm very
happy about this deal because it's a relatively sheep method to scan
my 6x6 transparencies and negatives.

I few weeks ago I decided to buy a Firewire/USB 2.0 High Speed-Combo
card to increase the scan time, i.e. to speed up the data transfer
rate.

Well, with the USB 2.0 High Speed interface it increases a little bit.
But, the theoretical speed of a high speed USB 2.0 interface (480 Mbps
or 60 MBps) won't be reached approximately.

Scanning a 6x6 negative or slide with 48 bit color in 2400 dpi will
give a filesize of nearly 160 MB and takes nearly 90 seconds. This
corresponds to a transfer rate of 1.8 MBps or 14.4 Mbps, far away from
60 MBps (480 Mbps) of highspeed USB 2.0. I seems to be more close to
USB 2.0 "standard" speed of 1.5 MBps (12 Mbps).

Actually I'd like to use the Firewire (IEEE 1394) Interface. And
although I removed the epson software and any related entries from
XP's registry, installed it new and tried to used the firewire
interface, it doesn't work.

In detail this means, the scanner itself is recognized already, but if
try to scan anything, the EPSON software "hangs". After a while, the
software reports the scanner isn't responding. Trying Epson's last
version of EPSON Scan (Ver. 2.65) doesn't fix the problem. The combo
card is based on an ALI-Chipset.

If I do the same using USB 2.0 highspeed interface all works well but
relatively slow, see above.

Any ideas what's going wrong?

What scanspeeds do you reach under similar conditions (colors /
resolution / XP based systems)?

Thanks and by for now

Hi Guido...

I respectfully suggest that you're confusing after scan
processing time of software running in the scanner with
transfer time.

USB 2.0 will be for all practical purposes virtually
instananeous.

I invite you to try this: Scan one of your 6 x 6's with
all of your "toys" (degrain, usm, ice, etc) turned on, and
watch the scanner. I think you'll see the scan start and time
go by, and as soon as the scan is done you'll hear the carriage
return to its park position. At that instant the scan is done.
Now, more time will go by (lots of it) as the scanner runs
internal software. Then finally the end product will be
transferred.

Try it again, with no toy options, and you'll see a vast
improvement in time, almost zero transfer time. The carriage
will park and in less than a second you'll see the image.

If you'll use twain, and move the windows just a bit so that
you can see a bit of the image space of the host software (I use
mostly psp) then you'll be able to see the image appear. Immediately

Bottom line - if there is any effective speed difference between
firewire and usb 2 it will be of no consequence at all in the
real world.

Take care.

Ken

 

[Guido Haase]

Many thanks for your detailed description and the valuable hints!
Hi Ken,

many thanks for your detailed description and the valuable hints!

Greeinx

Guido