OT: Digitising collections of microfiche - Re: Looking for opinions...

Fred Cisin cisin at xenosoft.com
Wed Mar 28 20:00:50 CDT 2018


>> If you start with a fiche viewer, then a lot of the mechanical parts, 
>> such as the fiche holder, are well under way.  You need to modify the 
>> card movement mechanism to be able to automate it, but you could put 
>> that part off until you confirm that the optical portion is 
>> satisfactory.

On Wed, 28 Mar 2018, Zane Healy wrote:
> This is the part I’m having trouble wrapping my brain around, but then 
> I’ve not messed with that many fiche readers.  I’m far more familiar 
> with film holders.  Too bad it isn’t a question a running 35mm film 
> through, as Beseler Negatrans would work for that.
Or gate of a filmstrip projector, movie projector (I used to deal with 
16mm microfilm, as well as 35mm), or just sprocket spindle from camera, 
etc.
> If you can take a fiche reader, and modify the fiche holder mechanism to 
> handle this, then you’d be most of the way to doing this manually. 
> Realistically a manual setup with a shutter release cable would still 
> let you fly through the fiche pretty fast.

BUT, are we talking about a single exposure for the whole card, and then 
isolating pages/frames later?  That is certainly EASIER, but needs 
relatively hig resolution imaging device.
OR, are we talking about a servo/stepper controlled device that maneuvers 
the card around, to shoot a separate exposure for each frame/page? 
Excellent resolution, but lots of mechanical work to make the positioner.
I was suggesting getting the camera and optics working while manually 
positioning the fiche card.  THEN deciding whether to put in steppers.
Don't tell anybody :-), but if I were to do it, I'd probably use head 
positioner mechanisms from floppy drives.

> I think Bellows would be the only sane way to approach this.  You could 
> do it with extension tubes, but they’re a pain.  Another thing to 
> consider is a light source.  You’re going to need a fair amount of 
> light, given the necessary extension to get the magnification.

I disagree.  Or maybe I don't quite qualify as "sane" :-)
If this is a bespoke device sitting on a table, with a permanently mounted 
digital camera in it, then I would definitely go with extension tubes. 
Yes, you would need a way to handle fine focusing, but that could be a 
rack and pinion rail moving the camera.
I do occasionally set the focus on the camera, particularly if it is 
"closest" focus, and then move camera in and out to find the focus.
Extension tubes, once properly configured require no maintenance, 
re-adjustment, etc., and are available in even fairly thin forms.
My first use of a lathe (half a century ago) was to shorten an 
extension tube 1.5mm
Bellows go bad with age; the leather rots, pinholes develop, ...
I need to do a thorough checkout before I use my view cameras or bellows.
Or find some Ubik.
OTOH, if this is not a dedicated device, and is going to be used for a lot 
of other stuff, then bellows has versatility.
The minimum extension for a bellows is substantial, but well within range 
for THIS, so that isn't meant as an argument against for THIS.

I have a FULL MOVEMENTS Kenlock/Hama bellows, similar to:
http://forum.mflenses.com/spiratone-aka-hama-bellows-master-sst-with-bellows-lens-t76002.html
that I am trying to setup to play with.  I have a 47mm Super-Angulon that 
will cover 3.25x4.25 that will have PLENTY of image circle for 
exaggerated movements on a digital camera.  But, I need to machine 
some thnner adapters.
Yes, a "technical" view camera made with a Sony Nex is not "sane".

>> My favorite source for that kind of information is a 1936 edition of "The Leica Manual" by Morgan & Lester.
> One of my favorite books, I think I’m up to 5 editions of it. :-) 
> You’d be hard pressed to find a photography book with more data in it!

It's not quite the information density of Knuth, but half a century ago, 
it handled all of my photographic reference needs other than film. 20? 
years ago, an early 1950s edition reinforced my suspicion that Vannevar 
Bush's claim for readable stopped motion of fast streaming microfilm was 
NOT feasible with the hardware that Bush "used" when he implied/claimed to 
have built his memex.  Sure was handy that the library was stingy about 
updating their collection.   Munchausen learned from him.


--
Grumpy Ol' Fred     		cisin at xenosoft.com


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