Quantcast

«

»

Aug 24 2013

A quick microscopy lesson

Since people were asking, this is my low-end videomicroscopy setup — the one I’m comfortable putting in a box and hauling out to the wilderness of a biological research station. “Low end” means, unfortunately, a few thousand dollars, but there are ways to shave that down a bit.

videomicroscope

Don’t cut too many corners on the optics, though. I’m using the Leica/Wild M3C here, because I like what I see in it. I just checked eBay, and found a model just like it for $620. There are equivalents that don’t have the fancy brand name; look into Lomo, for instance. You might be able to find off-off-off brand scopes like this for a few hundred dollars. Hot tip: don’t look at the magnification first. If someone tries to sell you an inexpensive scope for cheap by bragging about “1500x!” or something similar, walk away. Clarity and resolution are the features you want, not raw magnification. The best thing to do is look at something in the scope; if it’s blurry or has color fringes, forget it.

I did cut corners on one thing here: back in the lab, I have a nice fiber optic dual gooseneck illuminator that’s good and bright and lets me play with transmitted and epi illumination. I left it at home today! It was my one big mistake. Instead, I brought a small cheap lamp from one of our student scopes, and it was not at all adequate to the task. Good lighting is essential!

For image capture, there’s a couple of ways to go. On this setup, I brought a simple RS-170 surveillance camera which I attached to the phototube on the scope, which puts out a standard video signal; that went into a Sony Digital Video Media Converter, which has multiple outputs, including a digital video signal that I could run into my Mac laptop. I used BTV Pro as a cheap, simple image acquisition program. The compromise here is that the camera puts out a fairly low resolution signal, but it’s easily displayed in real time on the computer, so the students could watch an enlarged live video stream. I could also capture stills, video, or timelapse with the software.

A better alternative for resolution would be to scrap the video camera and converter altogether, and go directly to a DV camera or your favorite digital camera. The old Nikon Coolpix cameras were great: they have a threaded lens, and you could buy a simple adapter that would screw on, then you’d plug it into the scope phototube. Other cameras require a somewhat fancier adapter, and I’ve even seen adapters for the iPhone. I’ve got the Coolpix system in my lab, but have discovered the unfortunate aspect of letting students fiddle with them is that they get broken.

That’s the system, it’s fairly idiot-proof and it’s quick and easy to put together. The only thing I’ll change next year is that I’ll be sure to bring the fiber optic illuminator — it was just that the Wild is so damned solid and heavy as it is, that I just couldn’t grab the similarly heavy illuminator and bring it to the car in one trip. I was lazy. Next time, two trips.

26 comments

Skip to comment form

  1. 1
    Nerd of Redhead, Dances OM Trolls

    I was lazy.

    *Looks at the Pullet Patrol™ PZ Protection Posse, lying in a heap ignoring grog soaked corn*. You must be a fiend when you are energetic….

  2. 2
    myoglobinologist

    PZ, submit a video to the Imagine Science Films Scenes project! No narration or fancy post production necessary. http://www.imaginesciencefilms.org/programs/scenes/

  3. 3
    carlie

    . I’ve got the Coolpix system in my lab, but have discovered the unfortunate aspect of letting students fiddle with them is that they get broken.

    I got my Coolpix from ebay, and it will have to be pried from my cold, dead hands. The students don’t get to touch it. ;) And I got the cool adapters from a most wonderful colleague who had the same setup but got a grant to upgrade. I love it so much, and don’t understand why nobody else makes something similar.

  4. 4
    PZ Myers

    Yeah, compare the resolution. The video signal gives me 640×480 pixels, which is pathetic. Even a cheap digital camera is 5 megapixels nowadays.

    Unfortunately, I’ve had a parade of students march through the lab, and somewhere along the way, one of them decided to try and force fit the memory chip upside down in the camera, leading to bent/broken pins. It doesn’t work when you do that. (and this was despite having carefully printed instructions with photographs of how to do it properly right next to the scope.)

    I should probably just get another coolpix on ebay myself. And tell the students “NO! YOU MAY NOT USE IT EVER!”

  5. 5
    boskerbonzer

    Thanks again, PZ! The only part I currently own is the Coolpix, but hey, it’s a start. And now I’m also armed against my first impulse to just buy the most magnification that I could afford.

  6. 6
    madscientist

    Depending on the needs (how the microscope is used, types of illumination desired, etc) it may be possible to develop a much cheaper and rugged device – but I’m thinking either no eyepiece or you have to swap out the eyepiece for the camera head. A simple pellicle beamsplitter could give you the crappy 30fps video feed while permitting the megapixel camera to remain attached and ready for pretty pics. Another option is to cannibalize a Logitech C920 (up to 2000-something x 1500-something pixels at 2fps raw data, or 1920×1080 for 30fps MPEG video). There really is no excuse for cheap crappy illuminators these days when high quality illuminators can be made rather cheaply, but I guess the game is all about screwing the customer for every cent they’ve got.

  7. 7
    screechymonkey

    All of the Stuyvesant High alumni, including Frank McCourt, Ken Miller, and the President of Brown University, recommend Leica lenses, too!

  8. 8
    wondering

    Ooo – for people with smaller budgets, there are a lot of cool microscopes out there that hook directly into your laptop. Magnification is only 50-200 x but they are super great for kids or school classrooms. Image quality is up to 5 MP. Prices range from $50-$135.

    These plug into the laptop and use the laptop as the screen:
    http://quarkyscience.ca/shop/celestron-handheld-digital-microscope/
    http://quarkyscience.ca/shop/handheld-digital-microscope-pro/

    Or you can add a digital eyepiece camera to almost any lab-quality microscope. Cheapest is ~$200 for 1.3 MP all the way up to $600+ for 5.1 MP. My sister-in-law works in a hospital lab and thinks these are the schiznitt.
    http://quarkyscience.ca/shop/digital-microscope-eyepiece-camera-5-1-megapixels/

    * If these links are inappropriate since they go to a specific web store, my apologies, and please remove them. I don’t know if Amazon carries this sort of thing or not and didn’t look.

  9. 9
    anuran

    Ye gawds. Microscopy has come a long way since I was an undergrad

  10. 10
    shouldbeworking

    I can hear the stories tart now “remember that time at microscope camp…”. Those were the days.

  11. 11
    PZ Myers

    I just priced the coolpix. Under $100; when I bought it new, it was about $1000! I think I’ll just get a replacement.

  12. 12
    chigau (違う)

    That’s what I want.
    A hand-held microscope that plugs into a lap-top.

  13. 13
    carlie

    Under $100?!? I bought mine maybe three years ago and they were going between $250-350. They were still hot items, even at so old, because of their versatility.

  14. 14
    DLC

    Totally Nude Life! Extreme Closeups!

  15. 15
    jpate

    Heya, it’s my first time posting. I just wanted to point out that you might want to avoid using faux-Spanish to emphasize how cheap and inadequate an item is.

  16. 16
    ChasCPeterson

    Interesting that you’re recommenfing a dissection-type ‘scope (you look at the surfaces of objects illuminated by external light sources) instead of the compound type (shining the light through the object viewed). Pondwater organisms can be viewed either way; the lowest “scanning” power on a compund scope is typically 10 (ocular) x 4 (objective) = 40x, and dissection scopes if adjustable typically go 10x – 100x or so.

  17. 17
    ChasCPeterson

    and stop offending speakers of faux-Spanish!

  18. 18
    Callinectes

    You know, with a little jiggery-pockery you can turn a 10$ webcam into a decent electronic microscope.

    It might not be quite up to spec, but it kills an hour.

  19. 19
    René

    I couldn’t bring myself to read beyond “el-cheapo”. I happened to glance some commenters’ complaints about the “faux Spanish”. I agree.

    Even Minnesotan Murrican professors utter Murrican Stoopid Stereotypes™

  20. 20
    madtom1999

    And dont forget not to use an incandescent bulb for illumination! Used to have a superb victorian brass scope with a nice gymballed concave mirror underneath for back illumination and you could fry a daphnia in the water cell with that if you got the focus a bit to sharp.

  21. 21
    nich

    Impressive. Very nice. Let’s see Paul Allen’s microscope…

    ;)

  22. 22
    PZ Myers

    That’s something I should have mentioned: look at the base on the Wild. This is a very flexible system: there’s a place in the back to fit a light source and an adjustable concave mirror in the base so you can get that transmitted light, but you can also illuminate from above.

    This is not an optimal system for pond microorganisms (although it’s really good for the larger stuff), but my compound scope cost $20,000 and I’m not going to load it into a bus and haul it up to a research station.

  23. 23
    chigau (違う)

    it’s actually faux-arabic

  24. 24
    tccc

    Regarding the faux Spanish comments: Thank you for pointing out that is considered insulting by people. It never would have crossed my mind that it might be offensive. I will keep it in mind going forward and avoid using such constructs as it is clearly possible to use non offensive language to convey the same meaning.

  25. 25
    brucegee1962

    I’m envious of your students.

    When I was a kid, I always loved reading about microorganisms and looking at the cool, in-focus pictures of them. Cilia, flagella, nuclei, organelles — they all looked incredibly amazing! And I saw movies of them too (long before the days of video), and was very excited about the amazing world waiting to be discovered.

    So I bugged my parents until I got a home science microscopy kit. The prepared slides that came with it were cool for looking at plant cells, but of course I wanted to see something wiggling around down there. So I gathered samples from the scummiest ponds and puddles I could find, mucous from yucky places that were supposed to be teeming with germs. And I looked through my microscope, filled with excitement about the amazing world I’d read about, and I saw — grayish and blackish and greenish blobs. I looked up what kind of microorganism they might be, and the answer came back: pieces of dirt.

    So I prepared more slides, dozens of them, and gathered more samples. But for all the movement I ever witnessed under the scope, they might as well have been gathered from the surface of the moon. Later on, in high school, I looked through other microscopes, and on the rare occasions when they were adjusted and lit properly I saw: even more blobs of dirt. None of them ever did as much as twitch. And in due course I went off to college and became an English major, which is what I teach now. When my children went to school, I bought them their own microscope and taught them how to adjust it to see clumps of dirt all their own, but they’ve never seen anything moving down there either.

    Every once in a while, I talk to a biologist who assures me that looking into a microscope and witnessing organisms capable of movement is commonplace for them — even routine. I’ll grudgingly accept the evidence that they’re telling the truth, and aren’t just participating in an elaborate conspiracy. But those creatures they talk about might just as easily live on the barren plains of Yuggoth, as far as I’m concerned.

    So again, yeah — your students are very lucky.

  26. 26
    Reginald Selkirk

    This crowd-source project could be just what you need:
    Micro Phone Lens: Cell Phone Based Microscope

Comments have been disabled.