The Optical Swiss Army Knife

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Doc

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Nov 29, 2003
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The Optical Swiss Army Knife

The loupe (a small powerful magnifier) http://www.bushcraftuk.com/forum/showthread.php?t=9429&highlight=loupe is a popular and cheap tool amongst bush craft people. You can check knife bevels, study nature in more detail, examine proof marks on sporting arms, etc. For something that costs a fiver and fits in a pocket it’s well worth having.

Recently I found something rather better: the Emoscop.




Most people have heard of the German optical company Leica - they make arguably the world’s best cameras and binoculars. Their chief optical designer was Arthur Seibert ‘the Wizard of Wetzlar’, who left the company in 1948 to start up on his own.

Seibert’s idea was to produce an optical tool that is a loupe, a microscope, a monocular and a macro camera lens, all in one. He called it the Emoscop. It’s about 4cm long and comes in a natty leather case.

The device beaks down into three parts. The bottom lens is a 10x loupe. The middle lens is a 5x loupe. Screw them together and you have a 15x loupe. Add the top eyepiece and you have a 25x microscope. Remove the bottom lens and you have a 2.5x monocular, which will focus from infinity to very close distances (about 20cm!)



I’ve also heard of people using them as macro lenses for camera, reading microfilm, etc.

It’s made in Germany and the optics and engineering are Leica quality as you would expect.

The main problem is getting hold of one. They are still being manufactured, but in China. I’m told the optical quality is good, but the housings are now plastic, not metal. http://www.emoscop.com/ At 48USD I would have bought one if I lived in the US. However, tax and shipping drove me to international eBay, where I bought an original German one for a tenner - £40-£60 is more typical though.

A loupe is much easier and cheaper to get hold of, and is an extremely useful instrument. But if you are into natural history or geology then making the effort to find an Emoscop is well worthwhile.

http://www.monocular.info/emoskope.htm

http://www.submin.com/binocular/index.htm
 
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Doc

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Nov 29, 2003
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Sorry, pics didn't work:

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DSCF1965.jpg


DSCF1961.jpg
 

Toddy

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Jan 21, 2005
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An interesting subject :approve: thank you.

I have one of those wee loupes. It's sitting on the mantlepiece right now beside a model boat my father built :D I've no idea how old it is but the boat was built in the late 1940's and the loupe's been beside it ever since.

I'd love to get hold of a bargain such as yours :cool:
Are the plastic Chinese built ones worth the money do you reckon ?

cheers,
M
 

Doc

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Nov 29, 2003
2,109
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Perthshire
An interesting subject :approve: thank you.

I have one of those wee loupes. It's sitting on the mantlepiece right now beside a model boat my father built :D I've no idea how old it is but the boat was built in the late 1940's and the loupe's been beside it ever since.

I'd love to get hold of a bargain such as yours :cool:
Are the plastic Chinese built ones worth the money do you reckon ?

cheers,
M

I've not tried the current Chinese versions but reports on the net are good, and there is no doubt that the Chinese can make good quality optics.

I suspect that for most people a loupe is a better buy - £7 buys a good one and £3-4 gets a tolerable one. I like the additional benefits of the Emoscop but I'm into optics and microscopy. I have a microscope in the consulting room - though Infection Control would have a fit if I started culturing things myself.

When I was doing dermatology, we used to see patients with scabies. I once saw the consultant dig out the scabies mite, put it on a slide, and let the patient have a look at it:

Freaked out patient: You're not telling me I had one of THEM burrowing into me???!

Consultant Dermatologist: Of course not. You've got about a dozen of them.

Mind you, scabies mites are pretty scary under magnification.
 
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ged

Bushcrafter (boy, I've got a lot to say!)
Jul 16, 2009
4,981
15
In the woods if possible.
The loupe (a small powerful magnifier) http://www.bushcraftuk.com/forum/showthread.php?t=9429&highlight=loupe is a popular and cheap tool amongst bush craft people. You can check knife bevels, study nature in more detail, examine proof marks on sporting arms, etc. For something that costs a fiver and fits in a pocket it’s well worth having.

There's usually one in my kit somewhere. You didn't mention starting fires... :) :campfire:

...Emoscop. ... I bought an original German one for a tenner ...

That was a great find!!! I am soooooo jealous!!!

:thankyou: for the heads up, I'm off to search the world's auction sites now.
 

Doc

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Nov 29, 2003
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Although many film cameras have become worthless with the onset of digital, I see there is still a thriving market in Minox spy cameras.

I have a Minox monocular and it is well engineered.
 

shaggystu

Bushcrafter (boy, I've got a lot to say!)
Nov 10, 2003
4,345
33
Derbyshire
......The bottom lens is a 10x loupe. The middle lens is a 5x loupe. Screw them together and you have a 15x loupe......

probably demonstrating my complete ignorance about optics here, but, if you multiply something by ten and then again by five does it not end up 50 times bigger than when you started?

wonderful looking piece of kit by the way, i could see myself getting a lot of use out of one of those, i might have to look into getting one of the modern chinese ones

cheers

stuart
 

Shewie

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Dec 15, 2005
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probably demonstrating my complete ignorance about optics here, but, if you multiply something by ten and then again by five does it not end up 50 times bigger than when you started?

With most things in life yes :) With single optics your just layering up each time.
 

shaggystu

Bushcrafter (boy, I've got a lot to say!)
Nov 10, 2003
4,345
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Derbyshire
With most things in life yes :) With single optics your just layering up each time.

ok, erm, why? (i'm guessing the answer is going to be a pretty complex one, if anyone has a link to anything that i might be able to understand that'd be great, ta)

stuart
 

Shewie

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Dec 15, 2005
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ok, erm, why? (i'm guessing the answer is going to be a pretty complex one, if anyone has a link to anything that i might be able to understand that'd be great, ta)

stuart

Too complex for me but I think it's because of the way the light/image passes through the glass at a certain angle, thereby giving the magnification on the display surface/eyepiece. I think in the case of the Emoscop, by adding the extra 5x lens the image continues to grow at the same angle because of the close fit between the glass. If you were to increase the distance between the two then the image would become larger.

I'm probably miles off but that's how I understand it
 

shaggystu

Bushcrafter (boy, I've got a lot to say!)
Nov 10, 2003
4,345
33
Derbyshire
Too complex for me but I think it's because of the way the light/image passes through the glass at a certain angle, thereby giving the magnification on the display surface/eyepiece. I think in the case of the Emoscop, by adding the extra 5x lens the image continues to grow at the same angle because of the close fit between the glass. If you were to increase the distance between the two then the image would become larger.

I'm probably miles off but that's how I understand it

that makes sense, i think.
 

Doc

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Nov 29, 2003
2,109
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Perthshire
Shaggystu has asked a very good and original question that deserves an answer. It's a bit difficult to explain without a pen and paper.

Of course Stu is right : if you make something ten times bigger, and then make it five times bigger, it should now be 50 times bigger than the original.

But magnifying glasses don't really make things 10 times bigger. They refract (bend) the light rays, so that they appear to be coming from an object 10 times bigger (if you track them back to their 'origin' behind the lens, which doesn't really exist, hence the term 'virtual image'. All the additional lens does is bend the light again, by half as much again, so now it looks 15 times bigger. If you look at the picture of a convex lens with a virtual image: http://en.wikipedia.org/wiki/Lens_(optics) you will see what I mean.
 

shaggystu

Bushcrafter (boy, I've got a lot to say!)
Nov 10, 2003
4,345
33
Derbyshire
thanks for the reply doc, i had a feeling the answer may be a little on the complicated side, it would appear that i was right.
i think i've pretty much got my head around this but it's getting late and it's been a long day so i think i'm going to leave this until the morning when i have slightly better mental resources to throw at it and have another look.

cheers

stuart
 

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