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Grey
2010-Nov-04, 04:59 PM
Okay, so it's not a telescope, but it's still optics, and I figured someone here might have some recommendations. My (six year old) son would like a "high-powered" microscope. We talked about the fact that something like that would be pretty expensive, and he came up with the clever idea of asking Santa Claus for it, because then we don't have to pay for it. :doh:

So I'm putting on my elf hat and exploring the options. Even though he's only six, I know my son well enough to know that it needs to be a serious microscope, not just one of the toys they sell aimed at kids. Something comparable to what I used way back in high school biology would be sufficient, I think. That was capable of making out detail in individual cells; I remember trying to chase down paramecia and hope they'd stay still long enough for me to get a good look at their structure.

I'd be very happy if I could avoid spending more than a couple hundred dollars (it would be nice to come in lower than that, even, but I doubt that's possible). I certainly can't afford the thousands of dollars that I know professional microscopes usually go for. If it can be hooked up to a computer, that would be a nice bonus, but it's not strictly necessary.

Anyone have any recommendations?

Jeff Root
2010-Nov-04, 10:27 PM
If we can get a lower price by purchasing in quantity, I'll take one.

I have a Japanese-made microscope that I got on my tenth birthday.
It was pretty good for the low price it undoubtedly had. The objective
lenses eventually got gunked up by accidentally moving them into
whatever I was looking at while attempting to focus. That had the
greatest effect on the most powerful objective, which is very tiny--
barely a millimeter in diameter. A favorite target was spermatozoa...
once I figured out where they could be found. (It took a few years
after they first became available for study that I finally put one and
one together...) That gunked up the 40x objective pretty good.
Nomatter what your kid looks at, he will need some help cleaning
it up occasionally, until he learns how to do it himself.

The scope has a battery-powered light, but batteries for lights
run down quickly. I suggest looking for one with a dual-power
option so it can be plugged in at the desk but also operate in
the field.

ETA:

The page of instructions with the microscope reminds me that I
really should have used a specimen cover or a second slide over
the specimen, both to keep it from drying out and from gunking
up the objectives. But I wasn't given any specimen covers and
the supply of slides was pretty small.

-- Jeff, in Minneapolis

stktos
2010-Nov-05, 12:49 AM
Yes I too love Microscopes!
When I was able to save up the money I had a very hard time deciding between a microscope or a telescope. Nerdy I know. Telescope won out but not for long! :-)

A quick search turned up something like this (http://www.microscope.com/omano-om118b4-1000x-binocular-compound-microscope-p-709.html). Think it would be pretty good.

I also know that Nikon makes some VERY nice microscopes, as I work in a hospital lab and they are what we use. They are crazy expensive though. But the lesser ones without all the filters and phased light attachments may be priced reasonably.
Good luck with the search and keep your son interested in science!

Grey
2010-Nov-05, 01:36 PM
Yeah, I'm hoping to avoid the crazy expensive. The site you linked has some very nice looking options, with a pretty broad range of prices. Anyone have any experience with an Omano scope?

Barabino
2010-Nov-05, 08:25 PM
Look also for a stereo microscope; it's much better for insects etc, and it's much easier to use: no need for slides

http://en.wikipedia.org/wiki/Stereo_microscope

JustAFriend
2010-Nov-05, 09:25 PM
Dont forget the surplus dealers.

Surplusshed.com is a pretty good deal for optical stuff:

$120 - http://www.surplusshed.com/pages/item/t1480d.html
$240 - http://www.surplusshed.com/pages/item/t1528.html

Grey
2010-Nov-05, 09:39 PM
Look also for a stereo microscope; it's much better for insects etc, and it's much easier to use: no need for slidesNope. Those are certainly fun, but we've had a chance to play with those before, and he understands the distinction. He's specifically interested in something that can look at cells. Thanks for the suggestion, though.

stktos
2010-Nov-06, 04:55 AM
Yes I have used Omano scopes before. They are what we used in college and some grad labs. They were good. But I never got a real chance to use one out of the box. The other students did not seem to take very good care of them (shocking!). The oil objective was all junked up and the others were scratched. :doh:
But the better condition ones gave a nice view with smooth focusing.

Just a quick thought. If your going to end up getting a scope, put out a little more $ and get a Binocular head on it. The ones with a Monocular head always gave me eye strain and were just annoying to work with. The Binocular view was much more comfortable.

Romanus
2010-Nov-27, 04:37 PM
All I'll say is whatever you do, get a microscope with a fine-adjustment focuser. I spent years looking through cheap microscopes with coarse focus only, but when I first used one with fine focus in school...no comparison.

Evan
2011-Feb-06, 06:42 PM
An egg is a cell with an immense food supply. [grin]

Microscopes suffer from the same marketing hype that plagues telescopes. Power, more power! To bad it has the name "power". Somebody should'a named it "Image scale". Cells come in many sizes and many are very difficult to image with a light microscope. High magnification is a pain to use. It requires special lighting techniques using high power lighting, special stains, a microtome, high quality optics and the depth of field is terrible. The best microscopes use oil drop immersion to couple the objective to the specimen carrier.

Image scale is the degree of magnification obtained from the object to the display of the object. That display can be the perceived field of view or it may be an actual physical display. I have several microscopes and my favourite for most purposes is one I built myself. I should explain that I have a machine shop and have been building my own equipment for decades. Either way, shop made or purchased, a display microscope is a treat to use. Sharing is very easy since more than one person can look at the screen at the same time. I highly recommend looking for a microscope with a display instead of using an eyepiece. Effective magnifications of several hundred power are obtainable which is enough to image some larger cells (other than eggs).

This is the one I have built. It uses old 35mm camera lenses and that gives it both excellent depth of field but also a very large standoff distance to the specimen. The display is a very nice NTSC monitor that takes standard video from a cheap NTSC mini camera. The lens on the camera is removed and the 35mm lens projects directly on the sensor by using an extension tube. It works in precisely the same way as using extension tubes with the same lens on a regular SLR. The main difference is the image scale produced by the very small sensor in the video camera. That, combined with back focus distance produced by the extension tube gives considerable magnification. Additional image scale is gained according to the ratio of the sensor size to the display size.

Resolution in this case is independent of image scale and that limits the size of the details that may be discerned regardless of what the image scale may be. The display shown here has a resolution of 1024x720 so it produces a very sharp picture on a display that size. Also, by using an inexpensive USB adaptor the image may be captured directly to the computer. Great for those science projects and assignments.

http://ixian.ca/astro/vmscope1.jpg


http://ixian.ca/astro/vmscope2.jpg