Workflow for digitizing MF B/W negatives - focus stacking & pano stitching

Optical microscopes + digital photography
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michaelezra
Posts: 5
Joined: 17.08.2022 04:59

Workflow for digitizing MF B/W negatives - focus stacking & pano stitching

Post by michaelezra »

What a great software! I found this very useful for digitizing 6x7 film,
For anyone interested, my workflow is documented here:
https://forum.luminous-landscape.com/in ... c=141231.0


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michaelezra
Posts: 5
Joined: 17.08.2022 04:59

Re: Workflow for digitizing MF B/W negatives - focus stacking & pano stitching

Post by michaelezra »

In the article referenced above I describe how I use Helicon Remote for digitizing film negatives.
This is a task that requires a lot of repetitive work and I wanted to suggest a few improvements to Helicon Remote that would make it much easier, specifically for digitizing film.

The important aspect of digitizing film is that it is unknown which area of the non-flat film is closest to the camera and which is farthest.
This is an important difference, as opposed to shooting a focus stack of a regular 3-dimensional object.

In order to ensure that the set of images for focus stacking covers the full irregular curvature of the film, I first manually focus in the desired location, and then step back a few (N) steps, set position A, then step forward more steps (double N + 1 small) and set position B.
At this point A and B are set to be sufficiently far from the point of initial focus to encompass the full film curvature - and this is a trial and error at first.

I managed to program Automator and MacOS shortcut to perform these actions (and then auto-start the shooting sequence) within Helicon Remote and basically everything works.
Because I use Automator for the recorded screen actions in Helicon Remote, I need to keep the mouse over the application while Automator is sending commands to Helicon Remote. This unfortunately leads to a waste of time in simply waiting for all focusing steps, as I cannot switch to another application and do something else while this automation is running.

It would be very helpful for this type of workflow for Helicon Remote to support a Setting of +X and -Y steps from the AF position, and then Shoot.
So that +X and -Y could be set in UI directly (I am using 2 Medium steps back, 4 Medium steps forward, 1 Small step forward, leading to 8 frames at 105mm F5.6). Looking at all features that Helicon Remote already provides, this might be a not very complicated functional addition (just invoking an already existing capabilities via different UI element), but with a significant benefit for repetitive digitization of film.
Last edited by michaelezra on 26.08.2022 03:10, edited 2 times in total.
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Catherine
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Joined: 29.04.2019 22:38

Re: Workflow for digitizing MF B/W negatives - focus stacking & pano stitching

Post by Catherine »

"from the AF position" - do you mean that you perform autofocus for each frame of the film and proceed from there?
michaelezra
Posts: 5
Joined: 17.08.2022 04:59

Re: Workflow for digitizing MF B/W negatives - focus stacking & pano stitching

Post by michaelezra »

Yes, I auto focus once for each focus stack.
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