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  • #16
    Sorry, no more ideas!

    Originally posted by JRouche
    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.
    .
    Mike

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    • #17
      Geeeeees thats all I needed, another toy 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
      _____________________________________________

      I would rather have tools that I never use, than not have a tool I need.
      Oregon Coast

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      • #18
        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



        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.
        Free software for calculating bolt circles and similar: Click Here

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        • #19
          Originally posted by JRouche
          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:



          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:



          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:

          Last edited by lazlo; 05-09-2009, 11:34 AM.
          "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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          • #20
            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.
            Free software for calculating bolt circles and similar: Click Here

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            • #21
              Originally posted by Evan

              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...
              My old yahoo group. Bridgeport Mill Group

              https://groups.yahoo.com/neo/groups/...port_mill/info

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              • #22
                Originally posted by lazlo
                Hi JR,

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

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

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

                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
                My old yahoo group. Bridgeport Mill Group

                https://groups.yahoo.com/neo/groups/...port_mill/info

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                • #23
                  Originally posted by JRouche
                  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

                  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.


                  "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                  • #24
                    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.
                    Free software for calculating bolt circles and similar: Click Here

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