Monday, February 21, 2011

Adventures in Large Format Digital Photography: part 6: a new scanner camera

I am starting anew! After I got a bad back moving my box camera around, I've always wanted to reinvigorate the first generation scanner camera I made. It was built around a Agfa Ansco Viking Anastigmat f/6.3 lens from a medium format camera and a wooden mail inbox. The lens has incredible coverage. Here's a look with little modification to the sensor array plastic:

ScanImage015-contrast-sharp-flickr

When I used the lens on the first scanner camera with a highly modified sensor, it had coverage of about a 7 inch diameter circle.

The trick is not breaking the new scanner's firmware checking. As soon as I remove the pinhole lens array it started having issues. I had to add the pinhole lens back anytime a particular error message came back. I hesitated to modify the scanner because of the chance of permanent problem.

The new scanner (a Canon LiDE 90) was very sensitive to the position of the glass cover--it was very important to have the glass precisely in place to keep the initialization target in the right place.

Very, very carefully, I used a sharp x-acto knife to remove the plastic tabs and the two new rivets that go through the center of the CIS sensor board. I removed the LED light pipe by finding the tabs that hold it in.

Putting the sensor back immediately made it 'broke'. But I occasionally got it to work. In the end, it appears that unless there is illumination at the instant you hit the preview button in the TWAIN application, you will get the error 2,7,0. I'm still figuring this out.

large format flatbed scanner

4 comments:

TheDoctor said...

Tell me more about this scanner. Are you using the scanner (as I see set up) in a stand/housing so you can adapt the scan via a different lens? I mean, changing the focal plane so you can scan objects larger than the scanner's original bed would accommodate? Why not get a 12 mp camera? Many of them have twain software ready made and aren't that expensive. Some of the modern camera's have sucky lens'. Go with a high mp and decent lens.

TheDoctor said...

My comment was about the lens and scanner....

Dean W. Armstrong said...

The scanner is scanning the focal plane of the camera lens. This can produce an image much larger than a DSLR can.

TheDoctor said...

...and you hand built this device? So cool!