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We’re nearing the end of our fourth season of Journey to the Microcosmos, and over that
time, we’ve been able to see microbes through all kinds of lenses—literally—thanks to
James, our master of microscopes.
For the rest of us on the Microcosmos team, it’s been really cool to not only see the
footage that James has recorded, but also see the journey that he has been on with the
microscopes themselves.
Now, we’ve been able to make this journey because of all of you and the support you
have shown to this channel by watching and commenting and sharing with others, or even
and especially by supporting us on Patreon.
We’ve all been on this journey together, so let’s look back on where it’s taken
us, and also get a peek at where we’re going in the future.
In the first season, James started out with two microscopes.
One was a microscope that he assembled himself from different parts for under $200.
The other microscope was a Motic BA310 that he received from a microscope company shortly
after we started this channel.
And these microscopes give us so much beautiful footage, thanks in part to the different techniques
that James used with them, whether that was bright-field or phase contrast or darkfield,
or some other technique to manipulate the light shining on the microcosmos.
But these microscopes also had their limits, so we were really excited to see what would
happen when James bought a new microscope before the start of our third season: the
Zeiss Axioscope 5.
This new microscope came with higher quality objectives (which are the lenses on the bottom
of the microscope), as well as prisms that made it possible for us to look at microbes
with differential interference contrast microscopy, a technique that sharpened their features
and made them seem more three-dimensional on our screen.
We have videos exploring these different techniques and microscopes, so if you want to learn more
about them, we recommend checking those out because light is much weirder than it seems.
But we wanted to do a quick summary for reasons that are probably very clear from the title
of this video: we have upgraded our microscope!
The Zeiss Axioscope 5 was a very exciting change, but it was also an expensive one.
So when James bought it, he was only able to get two objectives: a 20x objective and
a 63x objective.
Adding that to the 10x magnification the eyepiece gives, let us magnify our samples by 200x
and 630x respectively, which is not bad.
But a standard microscope usually comes with 5-6 objectives for a reason: the microcosmos
is full of things both small and large to observe and there isn’t a one-size-fits-all
objective that you can use to observe everything.
So one of James’ priorities was expanding his set of objectives so that he could have
the flexibility to see the microcosmos at more scales.
And thanks to his recent upgrade, he’s now gone from a set of 2 to a set of six that
range from 5x to 100x and that gives us a magnification range from 50x to 1000x.
Since I have gotten my own prototype of the microcosmos microscope that we are manufacturing
thanks to backers of our kickstarter, I’ve been amazed at how important it is to have
this variety of options, and how much time I spend on the lower magnifications and well
as going deeper . So without further ado, let’s introduce
these different objectives by looking at a ciliate called Tetrahymena that’s taken
up residence in a rotifer exoskeleton.
With the 5x objective, we can see little dots swimming in what used to be empty space, but
it’s hard to make out the details.
When we move to the 10x objective, we can start to make out shapes of the Tetrahymena
and more of the emptiness around them, but it’s difficult to see the exoskeleton.
Then as we start to go up in magnification, the details of the exoskeleton become clearer.
It's cool to see more and more of those details as we zoom in.
And especially when we get to the 100x objective, which gives us 1000x magnification, you can
make out so much of the insides of the Tetrahymena, that they look like bags of very resilient bubbles.
Here’s another ciliate called a Pseudoprorodon that James looked at through all of these objectives.
At first it just looks like a little green thing floating around and knocking into stuff.
But as we go up in magnification, we can start to make out the subtle undulations of its
body, which shifts the different shades of green.
And as we look even closer, the green itself takes on a new life, revealing the perimeters
of the individual algae inside the pseudoprorodon.
Revealing those details inside the tetrahymena and pseudoprorodon comes at a cost.
We can’t see as much of the world around them, whether that’s the emptiness around
the rotifer exoskeleton or the objects that the pseudoprorodon keeps bumping into.
Whether or not you need those details depends on what you’re trying to learn or what we
are trying to show, and that’s why having the flexibility to look through a wider range
of objectives is such an exciting upgrade for us.
Objectives are our gateways to the microcosmos, and we’re excited to have all of these new
scales to look at.
We’ve also made some other upgrades so we can revisit techniques we used on our older microscopes.
Like a polarizer, because who doesn’t love this shiny, iridescent stuff?
But we’re not just sticking with what we’ve known.
Thanks to this upgrade, we’ve got a whole new way to look at cells: fluorescence microscopy.
And we are so excited for this one.
The techniques we’ve highlighted so far are all clever manipulations of white light,
a mixture of many visible wavelengths of light.
But in fluorescence microscopy, instead of illuminating our sample with that mixture,
we choose a specific wavelength of light.
That light is called the excitation light because, well, it excites certain structures
based on their chemistry.
And those excitable structures then emit some light of their own.
The emission light will then travel back through the objective, get past barriers that filter
out the excitation light, and then show up in our eyes as vivid color.
With our upgrade, we have four different wavelengths of light that we can use for fluorescence
microscopy, and the parts of the sample that we see fluoresce will depend on which light we use.
In this footage, we’re looking at the Pseudoprorodon that we saw earlier, only this time it’s
being hit with 385 nanometer light.
The red we see is the fluorescence from natural structures, this is called autofluorescence.
The rest of the organism is dark because it did not respond to that 385 nanometer light,
making the color all the more vibrant.
But the power of fluorescence microscopy is not just finding fluorescent structures that
exist in nature.
Chemists and biologists have developed all sorts of ingenious techniques to highlight
different parts of cells using fluorescent dyes and proteins.
James is working on building up his arsenal of fluorescence microscopy tools and techniques
so that soon, we’ll be able to dive even deeper into the microcosmos to seek out things
that have been hidden from us before, uncovering the unseen world inside the unseen world that
surrounds us Thank you for coming on this journey with
us and thank you to Brilliant for sponsoring this episode.
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The names that you’re seeing on the screen right now, they are our patrons on Patreon.
And they’re the reasons that we’ve been able to stay on this journey for so long and
also explore our world in such new and exciting ways.
We’re so excited to be using the resources from your patronage to do really cool things
so that we can see deeper into our world.
If you want to see more from our Master of Microscopes, James Weiss, check out Jam & Germs on Instagram.
And if you want to see more from us, there’s always a subscribe button somewhere nearby