Large Format Digital Scanning Back

  Now this is a project that will take some time. I have a mental picture of how this is going to work. I'm still deciding on how large an image sensor I want to use. Full frame allows me to take fewer shots during a full 4 x 5 inch image capture, but costs more up-front for the sensor; taken from a full frame digital camera.

  The idea here is to have an image sensor mounted on an x-y axis operated by stepper motors to scan the film plane of the view camera. The image would first be composed using the cameras ground glass. Then the ground glass would be removed in place of the x-y axis scanning back. A small micro-controller would control the stepper motors, and the number of positions at which the sensor stops to take a capture. These captures would be combined, or stitched, later to produce one very large image.

  If I were to use the sensor from a Sony a7, I could capture a total of 16 images. This is enough captures to cover the 5 inch width (with a lot of overlap), but not quite cover the 4 inch height. It is shy by about 6mm, 1/4". This would result in a stitched image of roughly 346MP! This accounts for some overlapping during capture. This could create a very large print.

  The controller could be set up to allow capturing fewer shots, say a minimum of four in the center of the image field. I will also set this up to take a set of shots across the full width of the frame, but only two (image sensor) frames high. This would be the panorama mode. The system would have to allow full motion of the view camera's movements; otherwise, what's the point of using the view camera. A key thing here is to be able to use the camera for both film and digital capture. 

  Obviously I'm limited to still objects, but even capturing the full 4 x 5 inch area, moving the sensor from place to place quickly, I don't think it should take more than ~20 seconds for all 16 shots. That's probably too long for a portrait, but good enough for a landscape or still life.

Cambo 4912x3264.jpg


More pictures and information to come as progress proceeds.

© Daniel Morrison 2014