[sane-devel] Scanner with most freedom of control for modification purposes... Lide25?

[netbox at pi-xi.net]

Hello,

I'm in a need for a scanner for rather special purpose, in which  
features such as:

- freedom to control the step motors
- turn the led lamps off during scan (if not, i'll just disconnect them)
- vary ccd gain and gamma for channels individually (i noticed that  
the canoscan lide 25 driver had this feature)
- ability to scan without the scanner head moving (work as a buffered  
streaming ccd camera)
- only powered via usb (no external power required)
- least autonomy and be most dependent on the software for best  
programmability
- control scanner focus (though i assume that with cheap scanners the  
focus is propably preset at the distance of the scanner glass from the  
ccd surface, this is actually even better)

In other words, the scanner would act as a digital scanning back for a  
certain technical photography purpose.

The scanner will be scanning the "film plane" surface at slow speeds  
and doing multiple scans for the same rows to increase SNR ratio  
(blending multiple "exposures" together with software that i'm writing).

I'm just curious if these scanners are generally able to "stream" the  
image data in for example simple raw data via the usb or are they so  
autonomic that they always perform a scan within the set range and  
output a jpeg/whatever with all the header information via the usb  
after they are finished?

And to the questions regarding: why not just use ccd? - I have access  
to a couple of digital backs but they are not an optimal solution  
simply because they output huge amounts of data at a time. I need only  
lots of data from a certain area of the film plane at a time. A 1 axis  
ccd row seemed like an optimal solution given that it can output far  
better resolution than any dv-camera or similar equipment. Also, there  
are some special lens requirements. So far the plan has been to hook  
the scanning back to a Mamiya RZ67, which provides an adequate  
scanning area of 6x7cm.

So, for a prototype, any suggestions of semi-cheap (<100 eur) scanner  
models which would allow as much control as possible via current SANE  
backends ? The canoscan lide25 seemed like a good choice for starters,  
but since my experience is restricted to film scanners, i have very  
little knowledge of modern consumer flatbeds.

Also, i'm looking for doing most of the job in software via a hooked  
laptop which powers the scanner so that minimal hardware modifications  
would have to be made, because i'm not keen in electronics.

Sincerely,
Otso Helenius