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02:38
December 4, 2011
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Long story short, a friend of mine found what appears to be a pretty good quality school microscope sitting in someone's trash. She nabbed it and gave it to me knowing that I was considering buying a scope for my boys. It is a Wolfe brand monocular scope. There are three objectives in the turret, a 4X, a 10 X, and a 45X. The eyepiece is a 10X. it has a sort of aperture selector ring under the stage to (I assume) regulate the light source. There is no light source, but I have a halogen lamp that fits nicely under it. I used some old lense tissues I had in my camera bag and a can of air to clean it off, then I got a box of prepared slides at a teachers supply place, and the scope seems to work really wonderfully (at least a lot better than I remember my old Tasco microscope ever working from when I was a kid back in the early 70s).
Here are my questions;
1) The objective lenses are screw mounts. Are they a standard size? Could I buy different lenses for the scope if I wanted to?
2) Though I blew the dust out and gently wiped the lenses, there still seems to be some dirt and smears. What is the ideal cleaning solution and lens cloth? Can I use isopropanol or is there a better option?
3)Is there some sort of inexpensive usb camera that I can mount on the eyepiece?
I'm sure I'll have a million other questions about stains and slide preparations, unless the kids turn out to be totally uninterested, then I may be selling the scope here. 
00:14
September 19, 2010
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Hi and welcome to the forum.
1) The objective lenses are screw mounts. Are they a standard size? Could I buy different lenses for the scope if I wanted to?
Check if the objectives have the number 160 engraved into them. If they do, then they can be exchanged with other 160 objectives, a very common standard. The 160 refers to 160mm tube length and is a standard (DIN). If the value is 170, then it is a Japanese standard. If the objective also has the value 0.17 engraved, then this refers to the thickness of the coverglass (0.17mm) for which it is optimized. Maybe you can post an image of the microscope.
2) Though I blew the dust out and gently wiped the lenses, there still seems to be some dirt and smears. What is the ideal cleaning solution and lens cloth? Can I use isopropanol or is there a better option?
Cleaning a microscope is a science in itself. No commercial cleaning solutions (as for eye glasses, monitors etc.) should be used. The solution should be very volatile and dry quickly, otherwise it may soften the kit holding the lens in place. I once read that a 80:20 ether:alcohol mixture works. Normally one should use the cleaning solution recommended by the manufacturer.
http://www.microscope-microsco…..e-lens.htm
http://www.microbehunter.com/2…..icroscope/
3)Is there some sort of inexpensive usb camera that I can mount on the eyepiece?
There are USB cameras available that replace an eyepiece. Otherwise it is possible to use afocal photography using a compact digital camera. Many people use this to make pictures. Read the February issue of Microbehunter Magazine for an article on how to mount a compact digital camera to a microscope.
Greetings, Oliver
17:41
December 4, 2011
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Thanks for the response, Oliver. I didn't see a 160 or 170 on the objective lenses, but I called the manufacturer and they were pretty certain that I had the standard 160 tube length based on my description. The scope doesn't have a model # anywhere on it, so I had to find something in there catalog that looked the same. The manufacturer is Carolina Biological Supply Co. The scope was manufactured in Japan for them, it appears. I can't even guess the age of this.
There is some rust near the lens on the 45X objective, but it doesn't seem to effect anything. The glass lens itself looks unscratched and clear.
The objectives are all Wolfe and they each have a value on them besides the magnification (4X has 0.10, the 10X has 0.25, and the 45X is 0.65). Are these the coverglass thickness you were referring to? And by "coverglass, does that mean the cover slip on a prepared slide? Will I have to use those thicknesses on slides I prepare?
All in all I'm very happy with the quality of this scope. As I said, it's far better than I remember my old Tasco microscope ever being. And it's better than I remember my High School Biology class microscope being, as well. I think those were already 30 years old when I used them, and they'd been pretty well mistreated by students over that time.
18:06
August 12, 2011
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Those numbers 0.10, 0.25, 0.65 are the Numerical aperture (NA) of each lens.
The basic rule is that the higher the NA the higher the resolving power (shows more detail) of the lens.
The lenses you have are low quality Achromat lenses, but that's fine. The best lenses are Apochromat lenses but these are much more costly than Achromats.
The Apo's have NA's of 0.16, 0.4, 0.95 for the 4x, 10x, 45x.
You have no control over the thickness of the coverglass on prepared slides. If you make your own slides buy 1mm thick blank slides and #1.5 coverglass (=0.17mm thick)
00:23
December 4, 2011
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Thanks for the info Tony. If I remember right from my old SLR days, the F-stop number was the ratio of the lens opening to the focal length of the lens. Is Numerical Aperture the same as F-stop?
Also, what is the difference between achromatic and apochromatic? The lenses I currently have certainly seem fine for my purposes, but now I wonder if I'll get to a point where I'd want to upgrade. It sounds like something I wouldn't really be able to appreciate until I get more experience with what I have. Is this the case?
09:34
January 6, 2011
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Hi Joesixpack,
NA is not the same as F-stop, numerical aperture is calculated with the formula NA=SinθXR where θ is the angle subtended between the objective axis and a ray of light passing through the object and being focused by the edge of the objective front lens, and R is the lowest refractive index medium the light passes through between the object and the objective (I hope that is clear).
A single glass lens will focus different colours in different planes, achromatic objectives have several different glasses which bring two dominant colours into focus in the same plane; apochromatic objectives separate three colours which are then corrected and focused by the eyepieces.
I would suggest you use the microscope and enjoy it, and when and if you want something "bigger, brighter, better", then do a laot of research and buy a whole new instrument rather than trying to upgrade this one. Just my opinion.
Good luck, and have fun.
Peter.
09:59
September 19, 2010
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Hello Joesixpack,
I have to agree with Peter. Do not invest anything in apochromatic objectives, they can be really expensive and you may not even need them. And: there are so many other available objectives as well (plan objectives, phase contrast… etc.) Most educational and introductory microscopes use achromatic objectives, and these are the standard ones. My microscope has achromatic objectives. There are so many other things that one has to look out for in a microscope and if you are able to keep up the interest in microscopy, then I would also get a new one later when you have more knowledge in where your microscopic interests are. I would consider a mount for a camera more useful than apochromatic objectives. At this stage I would probably invest the money in a box of ready-made slides, so that you and your children have something easy to look at. One useful possibility is to invest something in wide-field eyepieces, so that you are able to see a bigger area (at the same magnification), but this too is optional. Wide field eyepieces with a field number of around 20 (do not confuse with magnification of the eyepiece, which is usually 10x) give you less impression of looking through a tunnel. This adds more visual impact than mounting apochromatic objectives.
Oliver.
14:31
December 4, 2011
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Peter said:
Hi Joesixpack,
NA is not the same as F-stop, numerical aperture is calculated with the formula NA=SinθXR where θ is the angle subtended between the objective axis and a ray of light passing through the object and being focused by the edge of the objective front lens, and R is the lowest refractive index medium the light passes through between the object and the objective (I hope that is clear).
Yes, that is clear enough, thanks
A single glass lens will focus different colours in different planes, achromatic objectives have several different glasses which bring two dominant colours into focus in the same plane; apochromatic objectives separate three colours which are then corrected and focused by the eyepieces.
I would suggest you use the microscope and enjoy it, and when and if you want something "bigger, brighter, better", then do a laot of research and buy a whole new instrument rather than trying to upgrade this one. Just my opinion.
Good luck, and have fun.
The way things are at the moment I don't foresee any major upgrades to this microscope. As I said before, considering my current needs I think it's more than adequate. We're having a lot of fun with it as it is now. I think the next issue I'll be dealing with is slide preparation technique.
14:51
December 4, 2011
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Oliver said:
Hello Joesixpack,
… I would consider a mount for a camera more useful than apochromatic objectives. At this stage I would probably invest the money in a box of ready-made slides, so that you and your children have something easy to look at. One useful possibility is to invest something in wide-field eyepieces, so that you are able to see a bigger area (at the same magnification), but this too is optional. Wide field eyepieces with a field number of around 20 (do not confuse with magnification of the eyepiece, which is usually 10x) give you less impression of looking through a tunnel. This adds more visual impact than mounting apochromatic objectives.
Oliver.
As luck would have it my eyepiece is wide-field. The field of view is really outstanding. I'm shopping around for some more prepared slides. I paid $23 for a box of a dozen, but looking on line I see that they can be had for a lot less money. I saw some from Celestron that seemed very economical. Is that a good source? I see many that are cheaper, but they all seem to be plastic slides and I think I want to avoid those.
21:29
September 19, 2010
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The quality of the prepared slides can vary greatly. I do not know Celestron slides. Plastic slides do surprise me, this is the first time that I hear of plastic slides. I did not know that they also have those, especially because glass is not really expensive. I would also avoid those, also because the microscope optics are optimized for glass and also because the solvents used to prepare the slides may not be compatible with plastic. Amazon also sells prepared slides, you may want to have a look at some of the customer reviews.
Oliver.
22:28
December 7, 2011
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Hey, fantastic story!
Look, in my site you have a small amount of experiments/slides you can do with a basic microscope. I know that probably there are more sofisticated experiments, but this ones are nice too. and easy ;)
http://www.bestkidsmicroscope……xperiments
05:49
January 4, 2011
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Hi Joesixpack,
I purchased Celestron prepared slides 44412 (100 piece set) last year from internet. The quality is very good for most of them. Some slide may be a little hard to see, but it is only a few slides (less than 10). I am very happy with this.
Compare to my local prepared slide supplier, Celestron slides is better quality. All of them are glass slide. I can enjoy my microscope more with this slides and 100 of them take long time to see them all.
Cheers,
Suphot.
17:03
December 18, 2010
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When I bought my microscope I also bought a set of prepared slides PS100A they were all glass slides and of good quality at a good price try them you wont be disappointed, might have to clean a few.
http://www.amscope.com/Slide.html
17
13:24
October 29, 2011
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Hello Joesixpack from another Pacific Northwesterner (from Arlington up in Snohomish County),
Sounds like you & kids are going to continue to have a lot of good times looking through your excellent compound scope salvaged from the dumpster. Nice play.
You've already gotten your questions answered and received plenty of good advice from other reply posts. I would add a couple of thoughts just to stimulate ideas for future fun.
Sounds like you'll be buying a nice set of prepared slides – great – instant specimens. When you're ready to dive into making some of your own, I would recommend you read through the posts and and watch the videos on MicrobeHunter.com. Oliver and others have posted a bunch of stuff on making wet mounts and much more.
And be sure to buy some well slides for looking at critters that need a little more room to swim around. These are regular glass slides with ground-out concave depressions into which to drop pond water with algae and more. Add a coverslip on top and start searching for life. You can also use a well slide to make a hanging-drop slide. Put a drop of specimen-containing water on a coverslip; a quick flip upside down, and a gentle placement of the hanging drop over the well in the slide. Very cool.
One more thing. You asked about USB camera to mount on the scope. I recently bought a stereo low power scope (also called a dissecting microscope) from AmScope and a nice, easy to use digital USB camera was thrown in for very little extra cost. The whole package was very reasonable, too ($186).
You and your kids would find the stereo microscope an exciting addition to your current equipment. You can look at all kinds of things under lower magnifications than the compound scope – whole bugs and flowers, for instance – without having to make a slide preparation, and the images are in 3D!. PLUS the same camera could be used on both microscopes……
FYI – When I bought the scope, I upgraded to 3 megapixel camera for an additional $40 for better detail and resolution. You can shop around and mix & match for a good deal. My intention was just to find a 3D stereo scope – the camera was like a surprise freebee. Here's a link to the stereo scope I bought…if you do get interested, make sure you get one with two lights, one (reflecting) from the top, the other (transmitting) through the bottom. Very cool flipping back and forth with semi-transparent specimens.
http://store.amscope.com/se305…..-pz-e.html
Good luck, and happy hunting.
Avidor
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