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.RC.
02-25-2005, 04:01 AM
I am trying to make a fiche scanner out of my old fiche viewer printer....How it works is this I have taken all the printing parts out of the reader(it did not work) and have put my scanner in place where the paper used to go....So what I do is read the page want scanned then move a lever that positions a mirror to reflect the image onto the scanner....

Here is the problem...Scanners use their own light source to scan with however I will have to us the light source from the reader...I need to somehow disable the light source of the scanner so it only detects the light coming off the reader...Anyone know how to do this?????

Edit: I'm not real good at typing descriptions(or the english language) but have thought of a better description of what I am trying to do...

I am trying to scan a projected image with a normal domestic scanner....

[This message has been edited by Ringer (edited 02-25-2005).]

DBW
02-25-2005, 11:12 AM
<font face="Verdana, Arial" size="2">Originally posted by Ringer:
I am trying to make a fiche scanner out of my old fiche viewer printer....How it works is this I have taken all the printing parts out of the reader(it did not work) and have put my scanner in place where the paper used to go....So what I do is read the page want scanned then move a lever that positions a mirror to reflect the image onto the scanner....

Here is the problem...Scanners use their own light source to scan with however I will have to us the light source from the reader...I need to somehow disable the light source of the scanner so it only detects the light coming off the reader...Anyone know how to do this?????

Edit: I'm not real good at typing descriptions(or the english language) but have thought of a better description of what I am trying to do...

I am trying to scan a projected image with a normal domestic scanner....

[This message has been edited by Ringer (edited 02-25-2005).]</font>
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I too would also like to know about the inter workings of a scanner. I want to build a large format pin hole camera using a scanner instead of film which would require disabling the lite and slowing down the scan rate

nheng
02-25-2005, 11:32 AM
What you're trying to do is have the scanner pick up the "real" image in space that's left when you remove the screen from the equation.

It seems to me that the light from your scanner would not matter since it not longer has a "real" target. A bigger question, however, is how the scanner uses its own light. It may be on continuously or it may be pulsed in synch with the electronics ... I dunno.

You can get 35mm slide attachments for scanners and they backlight the slide with a diffuse (opal glass or other method) panel of light. This sort of says that it might work if the projected light is bright enough for the imaging chip.

Have you just ... tried it http://bbs.homeshopmachinist.net//wink.gif

[This message has been edited by nheng (edited 02-25-2005).]

Evan
02-25-2005, 11:37 AM
The light source is probably a flourescent tube, some Canon models use LEDS, In either case disabling the lamp will probably disable the scanner. In most cases the scanner does a quick calibration before scanning by advancing the scanning mirror assembly underneath the registration edge of the platen where there is a calibrated white strip. If the lamp isn't working it will usually cause an error. However, the good news is that you probably don't have to disable the lamp. If there is nothing on the platen the scanner won't see the lamp.

The bad news is that I don't think the scanner can focus on a virtual imaged focused at the plane of the platen without some help. Way back when Xerox came out with the first color copier they had a slide printing attachment for the copier. It used a standard slide projector and a mirror to reflect the focused image onto the platen. But, in order for the copier to focus the image a special fresnel lens was placed on the platen. I have no idea what focal length the fresnel lens was or if it was plano-convex or plano concave. You might try experimenting with the cheap plastic fresnel lenses that you can buy to stick on the back window of a motor home. They may not be fine enough though.

.RC.
02-25-2005, 06:34 PM
I have done some more experimenting and this is the result...

http://img.photobucket.com/albums/v606/OzRinger/fichescan11.jpg

This has been doctored a bit with photoshop elements....I think a better picture editing program would be able to sharpen it up a but more....Getting it to focus correctly is the problem...

What I ended up doing was take the front viewing screen and taping it to the scanner. Then put the scanner in the back of the viewer on a slight inclined angle forward....The light now comes up then hits a 6"X6" mirror set at about 45 degrees and goes back onto the viewing screen..I then have to focus the image onto the scanner(not very hard) then preview...Then I have to reverse the image and also reverse the colours....So far things are turning out OK...Looks like the light the scanner throws up does no damage to the end result at all...

Also does anyone know what the viewer screen is made of?????It looks like semi transclucent perspex....I will need a nother screen if I make this a permanent setup....

Here are a few more pics of the setup....
front view...
http://img.photobucket.com/albums/v606/OzRinger/fichescanner1.jpg

back view without scanner

http://img.photobucket.com/albums/v606/OzRinger/fichescanner2.jpg

back view with scanner installed

http://img.photobucket.com/albums/v606/OzRinger/fichescanner3.jpg

[This message has been edited by Ringer (edited 02-25-2005).]

Evan
02-25-2005, 06:49 PM
Cool! You should be able to buy some frosted acrylic sheet at a plastics supplier.

A little more adjusting...

http://vts.bc.ca/img/scan1.jpg



[This message has been edited by Evan (edited 02-25-2005).]

topct
02-26-2005, 10:44 AM
Brilliant. I was wondering how something like that could be made to work. Or even if it would work at all.

I was going to try and just hang the scanner in front of the view screen, but your method eliminates the focusing issue.

Gotta try it on some old motorcycle parts fliches.

Thanks,

------------------
Gene

aboard_epsilon
02-26-2005, 10:59 AM
is it not possible to scan the microfiches.....with a computer flatbed scanner.....then just blow them up with adobe so that you can view them
adobe also can turn them from negative to positive......all this will save all the bother perhaps....i dont know ..give it a try.
all the best....mark

.RC.
02-26-2005, 04:11 PM
<font face="Verdana, Arial" size="2">Originally posted by aboard_epsilon:
is it not possible to scan the microfiches.....with a computer flatbed scanner.....then just blow them up with adobe so that you can view them
adobe also can turn them from negative to positive......all this will save all the bother perhaps....i dont know ..give it a try.
all the best....mark</font>

No it's not unless you have a scanner with a scanning resolution of 100000000000000X100000000000000 pixels...Those pictures are mighty small and all you end up with is a big black blur...

Purchasing a commercial fiche scanner is also out of the question with the cheapest starting at $2000 and go up from there...

topct
02-27-2005, 10:32 AM
Ringer, would it make a difference if the glass on the scanner were removed and the view screen put in it's place?

Seems like the scanner having to see though two layers may have some effect. Just curious.



------------------
Gene

.RC.
02-27-2005, 04:13 PM
Yes I was thinking of doing that however I will need to get some frosted perspex first as the viewers screen is way bigger then the scanner...

.RC.
03-01-2005, 05:08 AM
I could not get frosted perspex so I got some clear and sandblasted it to make it frosted....I then took the glass out of the scanner and replaced it with the perspex with the following results.....

It looks like frosted clear perspex lets too much light through to the scanner so I will either have to get some clear coloured contact and stick on the perspex or look for some proper fiche viewer perspex...

I found by putting the frosted piece on the scanner it has enabled a crisp image to be taken....

I priced some proper fiche scanners on the web and they cost around US$2000+ new.

http://img.photobucket.com/albums/v606/OzRinger/testfichescan1.jpg

Evan
03-01-2005, 12:11 PM
Use a piece of neutral gray automotive window tint plastic film on the scanner platen to reduce the light. If it gives the correct brightness then you can permanently apply it to the perspex or the platen glass.