Question about Tasco 750 Monocular Microscope

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Microscopy; Relatively large spots on unknown surface obstructing view

Hey there,

I have a infinity light microscope and when I raise the condenser (or adjust the focus) to a certain height many spots with a bluish/red tinge appear in the field of view. I have turned the eyepieces, entire condenser (with attached filter), objectives and the spots remain stationary. I can't be sure whether it is dust or not, and I'm concerned they may be scratches, although the microscope is brand new. What do scratches/lens imperfections look like under the microscope? Also is there any other way of locating the problem?

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Re: Microscopy; Relatively large spots on unknown surface...


There is five part in microscope

1. Eye piece

2. Binocular tube


4. magnification changer or joom accembaley

5. illumination segment

Try to make it out which part is gives a effect to your vision.

as per my suggesition illumination asembely you just clean it first.

keep in touch



Posted on Feb 20, 2008

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Re: Microscopy; Relatively large spots on unknown surface...

Hey there to you too!

I suggest you don't have a problem at all. You are focusing on a ground glass filter somewhere in the light train. This serves the purpose of diffusing the light to give even illumination across the field of view.
When setting up, firstly use low power and a simple, easy specimen. Focus on this then rack up the condenser untill you see your annoying speckles. Rack up the condenser a little more untill the speckles just go out of focus. This is the position where your condenser should be for normal use.
Setting up the light source is the most important pre requasit for a good image, and there is a lot more to it than what I have already mentioned.
If I can be of any further help......Don't hesitate

Cheers and good hunting...Dave

Posted on Mar 10, 2008

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