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bob ward
05-06-2009, 09:38 AM
Does anyone have a recommendation for any of the USB microscopes currently being offered on ebay etc?
eg http://cgi.ebay.com.au/200X-USB-Digital-Microscope-Video-Camera-Webcam_W0QQitemZ230339570080QQcmdZViewItemQQptZAU_ Business_Industrial_Medical_Scientific_Equipment2? hash=item230339570080&_trksid=p3286.c0.m14&_trkparms=66%3A2%7C65%3A1%7C39%3A1%7C240%3A1318%7C 301%3A1%7C293%3A1%7C294%3A50

I guess that being a USB device they will work on a Mac OK, its just that in the ads they mainly refer to windows and vespa.

Evan
05-06-2009, 09:45 AM
Looks the same as this one at Dealextreme.com for $46.92 US.

http://www.dealextreme.com/details.dx/sku.11743

According to the user review at DX the Mac is no problem.



Pros: - works w/o drivers- solid (manual) magnification - picture decent on native, and not that bad on interpolation- fps is solid- leds can be turned off- videos can be recorded- snapshots can be done via software- drivers are hacked from logitech - mac osx users can use dinoscope software

Dawai
05-06-2009, 09:59 AM
Mine also plugs into a telescope.

PTSideshow
05-06-2009, 11:47 AM
Looks the same as this one at Dealextreme.com for $46.92 US.

http://www.dealextreme.com/details.dx/sku.11743

According to the user review at DX the Mac is no problem.

Check amazon for that one and a host of others there are a wider assortment of reviews most with the same complaints about moving when trying to snapshot it or adjusting the magnification.
:D

Evan
05-06-2009, 01:34 PM
. . . with the same complaints about moving when trying to snapshot it . . .

I expect that is why the review I posted mentions that "snapshots can be done via software".

A plus for it is that it adheres to the Windows Driver Model (WDM) so it can be used with many different webcam programs.

uncle pete
05-06-2009, 09:49 PM
I bought a "digital blue" brand for about $100 u.s. I bought it mostly for high magnification views of tool edges but found when veiwing anything over 60 x the lenses were too poor to give you good resolution. The microscope would have worked for what I bought it for but I gave it to my nephews son and bought the web cam system that was written up in Digital Machinist magazine awhile ago. It's a cheap system but will allow you to do edge finding ect. I'm still waiting for someone with far more computer skills than me to set up a program for angles,circles, gear teeth ect. You then have a dirt cheap fairly accurate system that would be close to a Optical Comparator or at least pretty good for the home shop, It would be great to grind a tool, Put it under the camera and compare your form tool shape against a accurate outline under high magnification.

Pete

JRouche
05-06-2009, 11:16 PM
Ok, maybe you guys can help me too. I have a Bausch and Lomb StereoZoom 7 Microscope and years ago bought a usb eyepiece hoping to see something usable. The pic is really bad. Mostly red and of poor quality.

The last time I was using it was to count the mesh of some silkscreen mesh. No good, just a reddish blob of what I can see with my eyeball.

And with the eye piece in there and my eyeball I can see the threads of the 300 mesh like they were 2" in diameter, I can see the scratches on the individual strands.

Im not really knowledgeable about microscopes. But my thinking is when I pull out the eyepiece lens thats say 15x Im gonna loose that magnification when I put the USB eyepiece in its place right? So that doesnt help me much, thats where all my magnification is, the objective lens isnt all that powerful..

So am I correct in thinking that I cant get the same image I see with my eye and the 15x eyepiece with anything available??

Or would of these 200x usb microscopes be adaptable to my zoom scope??

I would love to get the same picture I see with the 15x eyepiece on the computer screen.

I see these 5meg eye piece USB arrangements now but hate to spend the couple hundred bucks for them just to be in the same spot Im in now. My usb eyepiece is a 1.5 MP.

Any help guys??? Thanks abunch.. JR

Evan
05-07-2009, 04:01 AM
It takes very good optics to give a usable image at powers of about 50x or so. There are a lot of misconceptions surrounding all types of optical gear including telescopes, binoculars and microscopes. Unless you are trying to count the flagella on e-coli or something similar there isn't much reason to have more then about 50x magnification. Even then the requirements for the optical system become pretty stringent. Its because the depth of field goes down as the magnification goes up. Cheap lenses aren't achromatic which means they focus the different colours of the spectrum at different distances.

Because the range of acceptable focus goes down as the power goes up a cheap lens will become more and more out of focus and will exhibit severe colour fringing too. Even with good optics it can be a challenge to get a good micrograph.

I use my Nikon 4300 and simply place it to the eyepiece of my 40x stereo microscope. The image scale can be adjusted by zooming in or out with the Nikon lens.

Here are a few examples of the sort of image quality I am able to get with the Nikon. Keep in mind that the lens in the 4300 is about as good as it gets.

For reference the wire in this image is .001" OD
http://metalshopborealis.ca/pics2/finish2m.jpg

http://metalshopborealis.ca/pics3/pcbroutc.jpg

PTSideshow
05-07-2009, 05:57 AM
To early in the morning ;) and can't delete them any more

PTSideshow
05-07-2009, 06:01 AM
Here are some sites I found in wandering the net looking for a usb camera.
http://www.microscope-depot.com/home.asp

http://microscopestore.com/category.aspx?id=6

And of course the rest of the googled sites,:D
http://www.google.com/search?q=usb+microscope+camera&hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=Ek3&start=10&sa=N&cts=1240752215772

Haven't made up my mind yet but the first on described in this thread. Is the one I'm leaning towards.

Dawai
05-07-2009, 06:52 AM
They make a .3 and a .5 objective lens. Finding one that will work with your microscope is a ordeal.

Best way, type in the model number of your microscope and objective lens. People on ebay make money off frustrated people searching for something rare.

I'm still working on the box of microscope parts I bought off there, have some nice nikon widefield eyepieces now, hunting a objective lens now for increased work distance and reduced image magnification.

Each thing to do, you find out there is something else you must learn, not bad, but stumbling blocks.

Quetico Bob
05-07-2009, 08:24 AM
Here are 3 shots of a new insert, 10x, 60x and 200x (taken with a digital blue scope).
Cheers, Bob

http://i303.photobucket.com/albums/nn142/Queticobob/10x.jpg

http://i303.photobucket.com/albums/nn142/Queticobob/60x.jpg

http://i303.photobucket.com/albums/nn142/Queticobob/200x.jpg

mwechtal
05-07-2009, 12:55 PM
Ok, maybe you guys can help me too. I have a Bausch and Lomb StereoZoom 7 Microscope and years ago bought a usb eyepiece hoping to see something usable. The pic is really bad. Mostly red and of poor quality.

The last time I was using it was to count the mesh of some silkscreen mesh. No good, just a reddish blob of what I can see with my eyeball.

And with the eye piece in there and my eyeball I can see the threads of the 300 mesh like they were 2" in diameter, I can see the scratches on the individual strands.

Im not really knowledgeable about microscopes. But my thinking is when I pull out the eyepiece lens thats say 15x Im gonna loose that magnification when I put the USB eyepiece in its place right? So that doesnt help me much, thats where all my magnification is, the objective lens isnt all that powerful..

So am I correct in thinking that I cant get the same image I see with my eye and the 15x eyepiece with anything available??

Or would of these 200x usb microscopes be adaptable to my zoom scope??

I would love to get the same picture I see with the 15x eyepiece on the computer screen.

I see these 5meg eye piece USB arrangements now but hate to spend the couple hundred bucks for them just to be in the same spot Im in now. My usb eyepiece is a 1.5 MP.

Any help guys??? Thanks abunch.. JR

JR,
Did you try to re-focus after putting the USB eyepiece in? If so, it sounds like you never actually got focused. The view in the eyepiece, and the camera are not likely to be in focus at the same time.

I'd try setting the zoom on the microscope as low as it goes. That should give you more depth of field. Then focus looking at the monitor with the USB eyepiece in. You may even have to pull the USB eyepiece up a little if you've focused all the way out. If so, you can probably make a spacer to go under the USB eyepiece.

Since we don't know what the optics in the USB eyepiece are, you may have a REALLY high magnification setup. As Evan said, you don't need a lot of magnification for most uses. Sending the image to your monitor also causes an increase in magnification by itself. So, drop 'er down and give it another try.

JRouche
05-07-2009, 11:23 PM
JR,
Did you try to re-focus after putting the USB eyepiece in? If so, it sounds like you never actually got focused. The view in the eyepiece, and the camera are not likely to be in focus at the same time.

I'd try setting the zoom on the microscope as low as it goes. That should give you more depth of field. Then focus looking at the monitor with the USB eyepiece in. You may even have to pull the USB eyepiece up a little if you've focused all the way out. If so, you can probably make a spacer to go under the USB eyepiece.

Since we don't know what the optics in the USB eyepiece are, you may have a REALLY high magnification setup. As Evan said, you don't need a lot of magnification for most uses. Sending the image to your monitor also causes an increase in magnification by itself. So, drop 'er down and give it another try.


Thanks for the replies.. Um, well lets see. Yeah, I did focus it as best as I could, and tried moving the "camera" out a lil in the eyepiece, still a lousy picture. Even on the lowest setting for the scope, low mag.

Im just frustrated cause when I look at the sample pictures shown by the dealers of the usb cameras they all show full color, sharp images. My picture was like looking through a bowl of strawberry jello. Even at the lowest magnification.

I kinda think its the camera, it was only like a hundred buts. And as far as optics, I dont see any. I can look into the end of the barrel of the camera and see the chip (CCD ?) Is that normal?? Should there be optical lenses there??

I know there has to be a way.. And I do have a spare digital camera that I could use. But it doesn't link up to the computer.

I just want to be able to have images like this
http://cgi.ebay.com/7x-45x-Stereo-Zoom-Microscope-3MP-USB-Digital-Camera_W0QQitemZ170327615725QQihZ007QQcategoryZ582 92QQssPageNameZWDVWQQtcZphotoQQrdZ1QQcmdZViewItem
And Ill spend the money, but dont want to spend it with the same results as I have now.. Any help??? Thanks, JR

Evan
05-08-2009, 01:39 AM
They are awfully proud of that camera at the e-bay link. No way it's worth that much. You don't need to spend that sort of money either. All you need is a decent digital camera such as the Canon A470 or something like it. The ideal is a digital camera with a threaded ring surrounding the lens so that auxiliary lenses can be attached. This is what I have on my Nikon. Even without that you can get away with just sticking a magnifying lens in front of the regular camera lens. Put the camera in macro mode and full optical zoom. Then hold, or if possible attach a small magnifier lens to the front of the regular lens.

This is an example I just took today using a cheap
lens from a dollar store magnifier held by hand in front of the Nikon. I took this image at an angle to emphasize the very small amount of depth of field. The Nikon is only 4 mega pixel but to show how much detail it captures I included as the inset a small crop from the original image that hasn't been down sampled. The photo was entirely handheld. It is the Print Screen key on my keyboard.

http://ixian.ca/pics6/macro.jpg

mwechtal
05-08-2009, 12:54 PM
Thanks for the replies.. Um, well lets see. Yeah, I did focus it as best as I could, and tried moving the "camera" out a lil in the eyepiece, still a lousy picture. Even on the lowest setting for the scope, low mag.

Im just frustrated cause when I look at the sample pictures shown by the dealers of the usb cameras they all show full color, sharp images. My picture was like looking through a bowl of strawberry jello. Even at the lowest magnification.

I kinda think its the camera, it was only like a hundred buts. And as far as optics, I dont see any. I can look into the end of the barrel of the camera and see the chip (CCD ?) Is that normal?? Should there be optical lenses there??

OK, well I wasn't sure from your description if you had tried re-focusing. I wish I had some other brilliant suggestion, but unfortunately I don't.

I would expect to see the imaging chip in there without any intervening optics, but again, what I expect and reality may differ. ;)

I'm a lot better at diagnosing these things if I have it in my hand, but you may be right about the camera being defective.

lugnut
05-08-2009, 04:37 PM
Geeeeees thats all I needed, another toy:eek: I saw this post and couldn't help myself, I had to order one from ebay. Should help find those pesty little metal slivers I keep getting.
Mel

Evan
05-08-2009, 05:37 PM
I can look into the end of the barrel of the camera and see the chip (CCD ?) Is that normal?? Should there be optical lenses there??


I must have missed that part. The camera is intended to operate at what is called "prime focus". No eyepiece and no optics except the objective lens. This is how I usually take astrophotos with my telescope since it means there is no glass to cause chromatic abberation. It usually produces the best image although the magnification is more limited, not a bad thing.

It sounds like it isn't even close to the focal point of the objective lens. Focus the scope on a bright object like an illuminated LED or the end of a flash light. Then remove the eyepiece and hold a sheet of paper above the optical tube assembly (OTA) and see if you can find the focal point of the objective lens by forming a clear image on the paper. This will vary depending on the distance of the objective to the subject.

Estimate the distance from the end of the camera adapter to the actual surface of the chip. Do not touch it! The image must be focused on that chip which means that the chip, when mounted in place of the eyepiece, must be in the same plane as the image you focused on the paper. Have a look at the camera. You may find a line marked on it somewhere that indicates the focal plane of the chip. A lot of SLR cameras have such a line although few people know what it means.

Example: My Canon 300D

http://ixian.ca/pics6/focalplane.jpg

It may be the case that you can't bring the focal plane of the camera into the plane of the objective image. If the focal plane of the objective won't reach the focal plane of the camera then you need to move the objective further from the subject. If the camera focal plane is too close to the objective even at maximum extension of the position in the eyepiece holder then you need to make an adapter that allows the camera to be mounted further away, and easy job. I commonly used black PVC pipe to make thses sorts of things. Black delrin is also good.

lazlo
05-09-2009, 11:29 AM
I have a Bausch and Lomb StereoZoom 7 Microscope and years ago bought a usb eyepiece hoping to see something usable. The pic is really bad. Mostly red and of poor quality.

Hi JR,

I have the same microscope: a Bausch & Lomb StereoZoom 7 with a Mitutoyo toolmaker's X-Y micrometer stage:

http://i164.photobucket.com/albums/u15/rtgeorge_album/6ae6_3.jpg


But my thinking is when I pull out the eyepiece lens thats say 15x Im gonna loose that magnification when I put the USB eyepiece in its place right? So that doesnt help me much, thats where all my magnification is, the objective lens isnt all that powerful..

That's right -- you're removing the 15x eyepiece objective, and replacing it with a microscope camera that's meant for a camera port, so it doesn't have it's own objective.


So am I correct in thinking that I cant get the same image I see with my eye and the 15x eyepiece with anything available??

The way Bausch & Lomb intended for you to do with is with the StereoZoom 7 photoport. It plugs into the module on the back, and when you rotate the lever, it inserts a periscope mirror in the light path for the right eye:

http://www.optekusa.com/images/sz7photoport.jpghttp://i164.photobucket.com/albums/u15/rtgeorge_album/BLSZ7-27mm.jpg

You mount a camera adapter that has it's own objective in the 27mm photoport, and then mount the camera microscope to the assembly.

I bought a Diagnostics Instruments HRT-070 (which contains a .7x objective), but I need to make an adapter tube for the 27mm B&L photoport:

http://images.channeladvisor.com/Sell/SSProfiles/82000055/Images/251/J17D0101.jpg

Evan
05-09-2009, 12:27 PM
So am I correct in thinking that I cant get the same image I see with my eye and the 15x eyepiece with anything available??

No. The image scale will depend on the size of the chip vs the scale of the image produced by the objective lens. To calculate it you need to know the actual size of the active area of the sensor and the number of pixels it contains. The image scale of the objective is calculated by using the focal ratio of the objective to divide it's aperture. The final image scale is also determined by the display device so if using a large display the effective magnification can be very large. This however is limited by the resolution of the sensor so the effective image scale is that which is produced when the camera image is mapped to the monitor pixels 1 to 1. Most monitors display at 96 pixels per inch although there are some that are different.

JRouche
05-09-2009, 10:20 PM
It sounds like it isn't even close to the focal point of the objective lens.

Perfect Evan.. Ill give the steps you provided a try. Ok, so I think my CCD is a 1M pixel unit. With a 5M unit it will show the same picture right but with more usable info to be "magnified" or zoomed in on with my imaging software, right??

The red tint? I kinda thought it was because of too little amount of light. So I used additional lighting besides the microscope light I have and it didnt help, still red. Could be a bad unit?

Sorry for all the dragging on questions. Just wanna make sure if I do flop down some cash for a 5M unit I wont be buying the same problems...

Thanks, JR...

JRouche
05-09-2009, 10:35 PM
Hi JR,

I have the same microscope: a Bausch & Lomb StereoZoom 7 with a Mitutoyo toolmaker's X-Y micrometer stage:

http://i164.photobucket.com/albums/u15/rtgeorge_album/6ae6_3.jpg


Ummm!! Thats a very nice X-Y table you have there mister!! Im jealous...



The way Bausch & Lomb intended for you to do with is with the StereoZoom 7 photoport.

http://www.optekusa.com/images/sz7photoport.jpghttp://i164.photobucket.com/albums/u15/rtgeorge_album/BLSZ7-27mm.jpg


Great, the hits keep on coming, nuther nice tool. I like it.. Not gonna be able to find one of those for my budget :)

Thanks for the info.. Really nice setup you have there... JR

lazlo
05-09-2009, 10:46 PM
Ok, so I think my CCD is a 1M pixel unit. With a 5M unit it will show the same picture right but with more usable info to be "magnified" or zoomed in on with my imaging software, right??

You also need to know the size of the CCD (or CMOS) element.

Here's a good page from Diagnostic Instruments (the folks who make that camera adapter I posted above) describing how to calculate the field of view you'll see on your camera, given a CCD/CMOS element size, objective magnification, etc:

How to Choose Your Video Coupler (http://www.techinst.com/video%20coupler.html)

Field of View, Monitor vs., Eyepiece

The first question that most people as is: "How much of what I see through the eyepieces will appear on the monitor?" The field of view diagrams presented here will help to answer that question.

In each diagram, the circles represent the field of view seen through the microscope eyepieces. The rectangles represent the image that will appear on the TV monitor (or computer screen).

Each circle corresponds to a certain "field number" (FN) eyepiece. Eyepieces with wider fields have larger field numbers. The field number is usually engraved on the eyepiece right after the magnification, as in WFK 10x/20. In this example, FN = 20.

http://www.techinst.com/images/coupler1.gif

Evan
05-10-2009, 12:47 AM
The red tint? I kinda thought it was because of too little amount of light. So I used additional lighting besides the microscope light I have and it didn't help, still red. Could be a bad unit?


The red tint indicates that it is a CMOS sensor and that it is "blooming" from too much light which is saturating the red pixel amplifiers. That also indicates that your light source is too rich in infrared. You should try using a white LED as a light source instead of incandescent or fluorescent.