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View Full Version : Could the lens in an Epson scanner be replaced ?


Ken Lee
22-Sep-2010, 08:08
If the "optics" of these scanners is the limiting factor (not the sensor or stepping motor), could one "simply" replace the lens - with a better one ?
domaz
22-Sep-2010, 09:29
I think the problem is you'd need a lens that is exactly the same as the Epson's lens. Same focal length, same focus etc.. you are unlikely to find that on the surplus market. If you look at getting a custom lens made it's going to cost more than getting a better scanner. Maybe you could use a completely different lens if you modifed the scanner physically (to accomodate focus distance) and possibly changed the firmware as well.
Ken Lee
22-Sep-2010, 09:51
How might we find out which lens it is ? Perhaps it's a commodity of sorts, or a standard length.

I'm ignorant in this area, but aren't electronic devices made of such components ?
mdm
22-Sep-2010, 11:55
Open it up and have a look?

David
BetterSense
22-Sep-2010, 12:16
Since the scanners use linear CCDs, the lenses are long, linear 1-dimensional ones. I doubt you would be able to find something like that aftermarket, but maybe 1-D lenses are more common than I think.
Ken Lee
22-Sep-2010, 12:38
That explains why I have never seen anything round down there, which looks like a "lens". What we need is an electro-optical engineer.

Are any forum members electro-optical engineers ? :)
timparkin
22-Sep-2010, 12:48
Personally I think the limiting factor is 'halation' and the ccd response (thermal noise and bad red/blue response). Fixing the lens will only get you so far (and I'm not even sure how far that is... ). Buy a stupid cheap drum scanner and have fun.. :-)
Robert Budding
23-Sep-2010, 17:57
The CCD in consumer flatbeds will limit what's possible.

http://www.scantips.com/chap3c.html
JC Kuba
24-Sep-2010, 12:30
The stepper motor controls may have to be recalibrated if there a much difference in weight.
rco3
12-Oct-2010, 20:15
I wonder if it's possible to place a slit over the CCD somehow, in order to reduce the effective aperture and perhaps increase effective sharpness/DOF, similar to stopping down a camera lens...? You'd have to increase the exposure time. Doesn't VueScan support that?

Just thinkin' out loud, late at night.
domaz
13-Oct-2010, 09:41
I wonder if it's possible to place a slit over the CCD somehow, in order to reduce the effective aperture and perhaps increase effective sharpness/DOF, similar to stopping down a camera lens...? You'd have to increase the exposure time. Doesn't VueScan support that?

Just thinkin' out loud, late at night.

I had that same thought- you would also increase scanner noise of course. I don't believe VueScan can do a long exposure pass with the Epson scanners- I think it just does multi-pass. The trade-off in either case would probably be quality of the scan vs the time it takes to generate it.
Ken Lee
13-Oct-2010, 10:09
On reflection, the best way to get more out of an Epson scanner, is simply to increase film size.

A jump from 4x5 to 5x7 is more than enough (http://www.kenleegallery.com/html/tech/index.html#table) for me.
Mark Sawyer
13-Oct-2010, 10:36
Hmmm, wonder how it would look scanning things through a nice Verito...
Ben Syverson
13-Oct-2010, 13:20
On reflection, the best way to get more out of an Epson scanner, is simply to increase film size.
That's the same conclusion I came to... I realized that a drum scan of 4x5 and an Epson scan of 8x10 would be about equal. So for me, it works out that 8x10 is much cheaper than 4x5.
Bob McCarthy
13-Oct-2010, 13:58
That's the same conclusion I came to... I realized that a drum scan of 4x5 and an Epson scan of 8x10 would be about equal. So for me, it works out that 8x10 is much cheaper than 4x5.

hehe,

I looked at it the other way around. Shooting 8x10, how much film cost could I save if I bought a high end scanner and dropped to 4x5.

great scanners are really getting cheap.

I bought a Cezanne in like-new shape for only 2X an epson.

Only hole in the theory is I still shoot 8x10, but now scan on the Cezanne!!

bob
Jack Dahlgren
14-Oct-2010, 16:18
I had that same thought- you would also increase scanner noise of course. I don't believe VueScan can do a long exposure pass with the Epson scanners- I think it just does multi-pass. The trade-off in either case would probably be quality of the scan vs the time it takes to generate it.

The lens is already pretty small - I'd think diffraction would come into play.