Microscopy Forum

Have we got a useless microscope or is it bad technique or is it inappropriate usage?

We have a cheap 1/2 toy, 1/2 real, I suppose might be the way to describe it, l microscope. Cost about $50 from Australia Post. Bought for the little kids ( 8 and 10 ) for xmas.

Plastic thing.  Marked as having magnifications 200x, 400x, 900.

In fact we've got two of them.  Different brands, slightly different but essentially the same.  The second one goes to 1200x, it says.

They work.  We can see the attached specimen slides okay.

But we want to see stuff in pond water.  Read so much about it.  Seen so many youtube videos.

But we can't see anything!

Why? What's wrong?

I had some pond water with some  black specks zooming around in it.

Put a drop of that on a slide and looked and saw this black beetle like thing.  Seemed to have a slit right down its back like the wing carapace split in two if it were a bigger beetle.  And just one time I fancied I saw some antenna out the front thrashing away in a sort of breast stroke.

But I was never able to reproduce that.

So this black thing was most uninteresting because it was so big and black. Just blocked the light. Just a black lump.

And the only other 'life' we could see was much smaller specks of whiteness flying around here and there from time to time.

No great big protozoa or whatever they are that we see in all that youtube stuff.

Like these for instance:

which were supposed, if I read it right, to have been viewed at only 325x.

What's going on?  Can anyone help?

regards,

ab

That video you embedded was made with a microscope setup costing thousands of dollars and using a very sophisticated lighting technique (differential interference contrast). Sorry, but there is just no way to duplicate that with the equipment you now have. On the other hand, you should be able to see some one celled creatures with your scope if you have everything adjusted just right.

Hi AB,

You don't say how you collected your sample or how it looked.  If you scooped a jar of clear water from the body of the pond then you probably have only water.  You need some life in your water, include some mud from the bottom especially if it is producing bubbles, green slimy stuff from rocks etc., include plenty of the clear water you are trying to duplicate the pond in miniature.

When you first view your sample do not be too disappointed if you can't find much life it can take a few days for the sample to settle down and the community of protists to reorganise themselves.

Collecting samples is a learnt skill, practice and careful observation will guide you to finding interesting organisms.

Good luck.

Peter.

 Okay, thanks very much for the replies.

 So it is bad technique is the problem, mainly.

325x it said for that video.  I've seen some that say things like 60x.  But those lower magnifications quoted I suspect apply to only one lens – the total magnification much more?

So the question I should ask is:  What magnifications do we need to see typical pondlife?

I've collected more samples and managed to get some really stinky black mud and even some green slime.  Good?

Surprisingly hard around here to find that sort of thing.

I've been wanting to view Daphnia. That's what started this whole thing really. And I read Daphnia range from 1mm – 6mm.  So I'd expect to find them clearly visible.  But I've failed to find any at all as yet.  Any advice?

We do see many tiny – maybe 1/4mm at a guess – white specks flying around in the water we collect. But I fail to see them under the microscope so I still don't know what they are.  Any suggestions?

I can well believe the importance of collecting and preparing samples. I never ran across a job yet that didn't depend heavily on preparation.  And ours hasn't been good.  We're working on it.  Can still use advice, for instance:

We collect water samples – how can we best keep them and for how long?

I currently have them in empty plastic peanut butter jars (and suchlike) outside on the seed tray bench which is under a shadecloth.  Every couple of days I add some green water from the outside goldfish pond (which is merely an old cast iron bathtub) in the belief/hope that this will provide some food for whatever organisms I might have there.

And I have buckets of water of various origins, collected here and there.

And a bucket of rainwater.  I aerate the rainwater bucket from time to time with a little aquarium pump that sprays six streams of water across the surface.  Then I use that water to top up my buckets and my little plastic pots in the hope that this will provide enough oxygen for organisms to survive.

And (phew, lastly) I pour water from the little pots and from the buckets from one to another when I have one that seems very lively – many of those white specks zooming around, maybe some tiny black specks – in the hopes of spreading the 'life' around so's I'll end up with much.

A hoped for goal being buckets of Daphia I can feed the goldfish on.  I wonder if that's possible?

And here's a cheap new microscope I've found.  Would this appear to be worth a couple of hundred dollars or would the money be better spent elsewhere?

Model : RM-3LED
Stand: Stable & Robust assembled from Die Cast Aluminum Parts
Nose piece: Quadruple revolving with positive centering & click stops
Illumination: Mirror & LED Cordless Rechargeable Lamp
Objectives: SEMI PLAN JIS 10x, 40x Spring Loaded, 100x OIL SL
Eyepieces: WF 10x & 15x
Mechanical Stage: Detachable Stage 135x120mm, 75x50mm movement
Focusing: Separate Coarse & Fine
Condenser: Abbe NA 1.25 w Diaphragm & Filter Holder
Focus Stopper for Slide protection
Weight: 4 Kgs

Hi AB,

Daphnia are like gold, they are where you find them.  I have only found Daphnia twice, one approximately six mm species and one approximately one mm species, they also seem to be very transient.

The "white specks" you see "flying around in the water" must be able to be viewed under the microscope.  If one (or more) is sucked up in a pipette and placed on a slide with a small drop of water then trapped under a coverslip it should be rendered immobile and view-able, with practice (and luck) you will have the drop size right to immobilise the organism without actually crushing it

"stinky black mud" may have a lot of bacteria (but not much else) which a cheep microscope will struggle to resolve, partly because of their diminutive size and also their low contrast.

Topping up samples with rain water (or even tap water) is fine, however mixing from one sample to another may well be counter productive.  If one sample has a deadly bacteria, or apical predator and you spread these to the other samples you may winde up with little to view.

Daphnia can be used as fish food, some pet shops do it; so the easiest way would probably be approach a pet shop, purchase some Daphnia, and obtain advice on how to maintain a Daphnia culture.

I don't know about the microscope in your post, I would suggest you try before you buy.  Also you haven't listed (what I consider the most important thing) the numerical index of the objectives.

Hope this helps.

Peter.

Thank you for those posts.

Sorry I didn't get back earlier.

I've been chattering away on Yahoo Groups.

I've bought a Nikon Model G and have been busy getting it working.

And I have had numerous strange computer difficulties…

And I've been chasing a plethora of microscope forums and websites and whatnot…

So I've learned a lot and made some progress.

But I'm still full of questions…

Like, for instance, why do they mark microscope pictures with something like '40x' – that being the size of the objective lens?

Is it because there's some standard size eyepiece lens presumed?