Hi everyone, Thanks for the feedback everyone! Thanks for the info Povilas about the genesys backend. I do have some scanners that use it. Would you have some pointers for how to issue those commands to a scanner via the backend?
You're right Ralph, it might be easier to control them directly. I had thought of the buffer approach as well, maybe I'll experiment with that. Thanks, Joel On Tue, Jan 4, 2022 at 12:47 PM Ralph Little <[email protected]> wrote: > Hi, > > On 2022-01-04 9:05 a.m., Joel Penner wrote: > > Hello, > > > > I am doing microscopic focus stacking with mirrorless cameras. I have > > a Cognisys Stackshot rail that I am doing this with, but I also have a > > bunch of Canon 9000F & 8800F scanners, so I am wondering whether I > > could use the precision these devices have to move a camera forward by > > small increments. > > > > I have already been experimenting with attaching a stepper motor to a > > microscope, controlled by a Big Easy Driver and a Raspberry Pi. This > > person used a scanner for focus stacking by connecting a scanner motor > > to an external driver: > > > > > https://petapixel.com/2013/01/24/focus-stacking-macro-photographs-with-a-hacked-flatbed-scanner/ > > < > https://petapixel.com/2013/01/24/focus-stacking-macro-photographs-with-a-hacked-flatbed-scanner/ > > > > > > This would work for me, but would it be possible to manually move the > > scanner imaging head with SANE and the scanner's firmware and > > circuitry? Basically, I would need SANE to move the scanner imaging > > head forward by a tiny increment, pause for a few seconds for the > > camera to take a photo, move forward again and so on. I just need > > total control of where the scanner imaging head is moved to and how > > small the increments are. My goal is to use this rig to do timelapse > > microscopic focus stacked images of plant growth. > > > > Ideally, the scanner imaging head light would be turned off too but I > > could also use tape or disconnect the LED array. I have other scanner > > models as well if the firmware or drivers of these Canon scanners > > isn't suitable. > > > > Any ideas would be appreciated, thanks! > > > > Joel > > This *might* be possible if the usual movements that the scan head would > make are sufficient for your need. > > What you can definitely do is to arrange for the scan head to move from > home quickly to a start position and have the head move more slowly to > an end position (speed depending on the requested resolution) after > which the head would usually return to the home position. By controlling > the rate at which the scan data is received from the machine, you might > also be able to get the scan head to pause when the scan data buffer is > full. Within the SANE API, those are really your options. > > Some scanners have a more high-level control, such is the case with the > protocols that are handled by the pixma backend. I see that Povilas has > answered regarding the genesys backend and the scanners that are > supported there. The genesys controllers provide much more control over > the hardware. Even then, using the SANE API is going to be quite > limiting, but you could use the genesys code to directly control a > genesys scanner. > > Honestly, you might be better off harvesting the components from the > scanner and using an arduino or something. ;D > > Cheers, > Ralph >
