Focus Stacking with a Raspberry Pi – Specimen Adjustment for Easier Framing and Composition

    Focus stacker
    Focus stacker without light box. The lab jack visible beneath the specimen.

    Over the past month I have made some further improvements to make life easier to set up the specimen and to take the stacks.

    Finally a simple manual lab jack arrived from China which will give me 5mm of vertical adjustment. This is so small that it fits neatly on the stage, having a footprint of just 25mm x 25mm and weighing next to nothing.

    On top of this I have mounted a thin steel plate. All my plastic specimen mounting cards now have a very thin button magnet glued to them, which holds them tightly to the top of the jack while allowing rotation in the horizontal plane and z-y movement.

    lab jack
    lab jack

    At the camera end of the business there is now a second rail mounted laterally which allows fine adjustment in this direction to frame the image. This came from one of the many suppliers of such things on Ebay. It is not a precision item like the lab jack, but will do the job required at very reasonable cost.

    There is an additional light fitted at the front which is used to illuminate the stage while setting-up and provides enough light for the camera to see the specimen and to enable fine tuning of the camera and specimen positions. The main lights are now fixed to the equipment chassis and not the underframe which makes adjustment of the equipment chassis position relative to the camera much easier.

    macro rail
    macro rail

    More software changes have been incorporated to speed up and automate certain functions. For example, there are now three options that can be pre-selected to decide what happens at the end of the shot sequence – stay put, go back to park, or return to the first image. And there is now no need to go back to the park position to commence a shoot. I had put that into the software so that it would force a reset of the counter to allow for errors in positioning, however I have found the setup to be repeatable in this respect and so that precaution was unnecessary and just time consuming.

    All that remains is to make the control of the lights easier from the working position behind the camera, which entails a little more construction work and some wiring alterations. Then we will be done (perhaps!).

    By now you will have guessed that I get as much fun out of the construction of the rig as I do from taking pictures!

What’s it all about?

Here are my jottings about my photographic projects and activities. I have been working on a focus stacking macro photography rig. There are quite a few posts about that. In addition I write about other photographic activities as and when!


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