A quick post to share some observations



Dear foldscope community:

This is going to be a short post  due to such a busy time I am having. Just wanted to share with you a bit of the  hidden beauty  foldscope is allowing many of us to unveal. Isn’t this a gorgeous adventure!

A few days ago I was trying to image epidermal tissue of a red onion in order to register the changes undergone in different osmotic media, that is to say, in water first and in a high concentrated dilution after. As you might know, this is a very common lab experiment accomplished by high school students. To be honest, my goal was to design some easy way to image the process  alive, which meant changing from tap water to salty water without moving the slide from the foldscope I was using. I practiced a long cut in a PVC slide y made for this ocassion but it failed, even after three or four tries. Nonetheless, I was completely overjoyed at the images that resulted. Using a foldscope has let me understand we are also playing with light (or light is playing with us) when we observe samples,  and this is a fact imposible to facilitate using a regular microscope.  Please, watch next images and see what I mean.

IMG_4147You can almost touch the cells and feel the slight roughness of its surface. I felt amazed!

When the cell underwent plasmolysis, the vacuole containing pigments (anthocyanins, mostly) shrinked and, for the first time in my life, I saw such clear junctions between the cell membrane and the cell wall (Hetchian strands).


I have gone through these images  many, many times and believe they are very beautiful. As I said before, osmosis is a familiar practice for many of us, but foldscope-light duetto has made it different. Simply wanted to let you know.

Till next time

Cristina  Bosch

9 Comments Add yours

  1. WOW! What gorgeous, perfect images of yes, a standard, but important exercise. Is there a post on the PVC “Y slide” you used for this? I’d be really interested to use such a slide for some experiments. Also, how did you manipulate the light for such amazing detail? Thanks for the beautiful images! so inspiring.

    1. Cristina says:

      Hello! Thanks for your comment. I used a PVC slide Foldscope team sent me when they considered I could be a “superuser”. It is an amazing invention you can make by yourself using a PVC transparent sheet. Lacksyier wrote one post where he used such materials in order to build an aquarium for microorganisms. If I am not doing this wrong, here is the link: https://microcosmos.foldscope.com/?p=16915
      There, he directs you where you can buy it. It is an awesome invention: you can bend it, use it indefinitely, change widths when convenient, etc.

      “Y” is just a grammar mistake. Sorry. I should have written “I”.

      I like afternoon sunlight. It is different, not strong neither weak, just the right intensity. Play moving your foldscope changing the angle it reaches your sample. That is what I do! Nothing special. Good luck!🍀

  2. Manu Prakash says:

    @Cristine: These are some of the most spectacular images I have seen anyone capture with a Foldscope. What an inspirational post – I know what you mean when you said, we can almost feel these cells. I will never say anything about “onion cells” anymore 🙂


  3. laksiyer says:

    This is absolutely fantastic Cristina. The focus is perfect. I am quite inspired. I hope you get the process in action. I wonder if you tried a thin PVC coverslip and a well slide. I shall try this at my end and see if it can be captured live.

    1. Cristina says:

      Hello, Laksyier! Yes, I used a thin pvc coverslip. I suppose it is the clue for the focusing improvement. BTW, I wonder how can I add water without moving the coverslip. I would like to film a fern /moss sporangium in action. It amazes me how “dead cells” still play essential roles in plants. Cell walls definitely are responsible of so many facts!

    2. Cristina says:

      And I also prefer using a tablet with a good camera. The screen is bigger and that makes it easier! 😃😃

  4. laksiyer says:

    I meant captured in action.

  5. laksiyer says:

    @Cristina. There are a couple of solutions that come to mind. One simple one is by @Mitali .. https://microcosmos.foldscope.com/?p=19439. She tapes three coverslips together and then introduces the liquid. Note the unusual way in which she mounts the slides on the foldscope. Essentially its like using a long coverslip. The other is to make a long ditch with a thicker PVC so that it juts out from the foldscope and then you can gently lift the thin PVC and introduce the liquid. One other thought is to have some paper under a coverslip with an end sticking out and drop the water on the paper . Hope to try these at my end too.

  6. Manu Prakash says:

    Dear Cristia,
    I often watch these images – they are so spectacular.


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