Microscope Question

[mikecable]

I acquired the above microscope for free. It is a Seiler Westlab medical microscope. The two eye pieces are WF10X--18 mm. The objective lenses are 4/0.1, 10/0.25, 40/0.65 and 100/1.25 Oil. All of the objective say 160/0.17.

What objective lenses, eyepieces, ring lights, barlow lenses would I need to change this into less of a biological microscope, and make it better for fossils? I think I have an idea, but I'm not a microscope expert, despite being a science teacher.

This appears to be a fairly decent microscope. Worth modifying?

[jkfoam]

If you acquired this microscope for free you are very fortunate. If it were mine I would leave the microscope as is and go on e-bay and look for a binocular disecting microscope for my use with fossils. I think the cost to convert the scope, if even possible, would be greater than the cost of a microscope from e-bay. The 10X eyepieces you have are good, but you would have to completely replace the objective lenses and their mounts. The stage would need replacing and I don't know if the body of the microscope would accomodate all that to give you the working distances needed.

You might want to consider some of the digital microscopes available now instead of an optical microscope. I have a Dino-Lite digital microscope that is really good for fossil hobby work.

Jim

[mikecable]

If you acquired this microscope for free you are very fortunate. If it were mine I would leave the microscope as is and go on e-bay and look for a binocular disecting microscope for my use with fossils. I think the cost to convert the scope, if even possible, would be greater than the cost of a microscope from e-bay. The 10X eyepieces you have are good, but you would have to completely replace the objective lenses and their mounts. The stage would need replacing and I don't know if the body of the microscope would accomodate all that to give you the working distances needed.

You might want to consider some of the digital microscopes available now instead of an optical microscope. I have a Dino-Lite digital microscope that is really good for fossil hobby work.

Jim

Jim

I wasn't planning on using it for fossils in matrix--only micros suitable for slide mounting. I thought I could swap the oil immersion objective with a 2X objective (about 50 bucks), and the two 10X eyepieces with two cheap 5X eyepieces (20 bucks for a set). With the 5X eyepieces this would give my 10, 20, 50, and 200 power. With the 10X eyepieces it would give me 20, 40, 100 and 400 power. I don't see myself using the oil immersion objective, but I would still have it if needed. Add some top lighting and I thought I might be good to go. I realize now that barlow lenses and ring lights are designed for the other type of scope. But I have a Gorilla tripod LED light that should provide fairly good top lighting.

Mike

Edited February 14, 2013 by mikecable

[pleecan]

Hello Mike: I own many many microscopes more than 20 ... looking at micro fossils are fine.... what you have is a transmission light microscope. Fossils tend to be opaque.... so you need illumination from above to see them... shine a desk light from above to see the fossil... for micro fossils 20x to 50x should be good meaning 2x to 4x or 5x objective... the trouble with the 2x objective is that there may not be adequate clearance between the specimen on objective so I would advise not getting 2x objective... I have 2x objectives and most of my microscopes will not take it as you run out of clearance... I would not go higher than a 10x objective as you loose rapidly the depth of field of view......

160 = 160mm barrel length of microscope= std

0.17 means the thickness of the cover slip

the first digit is the magnification... follow by Numerical Aperture= N.A. the higher the number the greater the resolving power and the shallower the depth of field of view.

Dissecting scopes can be have for less than $100 and this is what you really want for viewing fossils... generally up to 40X.

There is also a special class of high resolution microscope for viewing fossils.... Metallurgical Microscope mounted on a Boom Stand....

Hope the above sheds some light.

Peter

[mikecable]

Hello Mike: I own many many microscopes more than 20 ... looking at micro fossils are fine.... what you have is a transmission light microscope. Fossils tend to be opaque.... so you need illumination from above to see them... shine a desk light from above to see the fossil... for micro fossils 20x to 50x should be good meaning 2x to 4x or 5x objective... the trouble with the 2x objective is that there may not be adequate clearance between the specimen on objective so I would advise not getting 2x objective... I have 2x objectives and most of my microscopes will not take it as you run out of clearance... I would not go higher than a 10x objective as you loose rapidly the depth of field of view......

160 = 160mm barrel length of microscope= std

0.17 means the thickness of the cover slip

the first digit is the magnification... follow by Numerical Aperture= N.A. the higher the number the greater the resolving power and the shallower the depth of field of view.

Dissecting scopes can be have for less than $100 and this is what you really want for viewing fossils... generally up to 40X.

There is also a special class of high resolution microscope for viewing fossils.... Metallurgical Microscope mounted on a Boom Stand....

Hope the above sheds some light.

Peter

Based on your advice, should I just try the lower power eyepieces--5X, which are cheaper than the 2X power objective? That would give me 20X and 50X power on the low end. It would cost 20 bucks for cheap Chinese lenses, up to 80 bucks for what might or might not be better optics.

Next question. If I want a reticle eyepiece on a binocular scope do I buy just one, or do I need them for both tubes?

Finally, I always hesitate on digital scopes. I've got more than one at school, and despite being fairly tech savvy I find it very difficult to find drivers for them, much less software that works. Maybe I'm missing something. But I have never had much luck with digital scopes.

[painshill]

... I always hesitate on digital scopes. I've got more than one at school, and despite being fairly tech savvy I find it very difficult to find drivers for them, much less software that works. Maybe I'm missing something. But I have never had much luck with digital scopes.

I agree… it’s a real problem with digital scopes. Windows 7 (and I guess it will be the same with subsequent versions) no longer even allows you to install “unsigned” drivers unless you have paid for the full professional version. I gave away my last digital scope because the drivers were unsigned and when I moved my PC from Windows XP to Windows 7, the drivers for the scope wouldn’t work and no updates were available. Up until then you could install unsigned drivers by ignoring the (normally over-cautious) Windows warning message.

If you want to go digital, the safest bet is to go for a scope that doesn’t have its own drivers (ie it uses the drivers available within Windows). I replaced my scope with one from Bresser in Germany (Celestron seem to have identical models) which does exactly that and am very happy with it. The one I have now comes with illumination above and below the stage, has an LCD preview screen and a slot for an SD memory card. You don’t have to run it linked to a PC all the time… you can use it stand-alone and then upload the pictures from the memory card at your convenience.

One other thing to watch out for is that at higher magnifications, you’re restricted to transmitted light only and the clearance between the objectives on the turret and the stage is small, so you can’t do really high magnifications on thick specimens… those higher magnifications are designed for thin sections.

For thicker specimens I use an inexpensive “hand-held” model from Celestron, which comes with a stand. You can easily overcome the “clearance between objective and specimen” problem by placing the stand on a pile of books and weighting it down for steadiness. I actually drilled a couple of holes in the stand and screwed it to a wooden block as a platform, using the pile of books to adjust the specimen height.

[pleecan]

Based on your advice, should I just try the lower power eyepieces--5X, which are cheaper than the 2X power objective? That would give me 20X and 50X power on the low end. It would cost 20 bucks for cheap Chinese lenses, up to 80 bucks for what might or might not be better optics.

Next question. If I want a reticle eyepiece on a binocular scope do I buy just one, or do I need them for both tubes?

Finally, I always hesitate on digital scopes. I've got more than one at school, and despite being fairly tech savvy I find it very difficult to find drivers for them, much less software that works. Maybe I'm missing something. But I have never had much luck with digital scopes.

I would go with 5x eyepiece..... one reticle should be enough... if you get a digital eyepiece make sure it is compatible with win 7.... I have a high resolution digital eyepiece but no drivers for win 7...