Microscope Parts Help

[arduic]

I recently inherited this beautiful amscope microscope but I've run into an issue while trying to get replacement parts for what is missing.

I can not find a single label on this thing telling me what amscope product it actually is. Does anyone know of a way to figure this out? How am I supposed to know if this is an SM or a ZM series microscope?

Additionally if people can help me determine what I am missing I would be so appreciative. I can tell I am missing 1 eye piece. Since I want to do SMD PCB work I definitely want to get a barlow lense. However I can not tell if there should be something after the black piece at the bottom of the scope.

The zoom on my microscope also seems completely out of wack. This could be from lack of necessary equipment but when a PCB is in focus under the scope the work area is maybe 5% of my view the rest is all black. Do I just not have a scope made for PCB work or is my lack of some equipment causing the issue?

[Sensorcat]

You definitely have a microscope for inspection work or the like. You can expect a magnification somewhere in the range 5x to 100x and a working distance of 75mm to 150mm (3 to 6 in). If complete, it should be well suited for SMD PCB.

Are you familiar with microscopes of this kind?

Assuming you are not, try this: At first, set the magnification to the lowest value. The magification is set with the knob that has the numbers printed on it. The numbers are not the total mangification, because the eyepiece also contributes to it. Then, find the focus distance by moving the microscope head up and down in the range mentioned above. If you don't get it focused in this range, something is wrong. If you get a sharp image outside the proper distance range, something is still wrong.

Check the black bottom part: A lens should be in it. If you look at an empty tube, and the first lens is way more up in the microscope, a part is missing.

Did you get the microscope from a working lab environment or from a pile of abandoned instrument parts? If it is the latter, the eyepiece probably does not belong to this microscope, someone just put it there because the tube diameters matched. This is a possible explanation for the small image you see. It is difficult to say how it should be, but 5% of your view is not enough.

[jpanhalt]

It is missing an eyepiece/ocular.  It is hard to tell whether the present eyepiece can be focused to accomodate for a difference between your eyes. (The focus is usually part of the tube into which the eyepiece fits.)  That ribbed ring under the remaining eyepiece may do that. 

While not required, I usually buy eyepieces in pairs, unless I am buying the same.  Remove the eyepiece and measure its outside diameter.  There are only two standard eyepieces of that approximate size.  There is a 3rd common and older size that is considerably smaller in diameter.  Then decide whether you need wide field (WF).  They are almost essential for those who want to wear glasses while using.  I always get WF and suspect that remaining eyepiece is WF because of its top diameter.  WF allows even those who don't wear glasses to have more leeway in how close to get.

[jfiresto]

The right side sure looks like it missing the eyepiece. Is that the side, down which you are only seeing 5% of your view?

What is the view through the left side? Do you see the full field of view out to a sharp, black boundary? If that is good, how is the view through right side when you transplant the eyepiece to there?

The magic words if you wear glasses are "high eye point" eyepieces or oculars. A wide field eyepiece refers to something else, to the field of view, which for some sellers can be as little as 10X/20mm (20mm FOV and 10X magnification) – which is not really wide. 10X/22mm or 10X/23mm is more like it.

Any chance you could post a picture of the other, business end of the microscope to show, I presume, the converging pair of objectives?

[arduic]

Thank you for all the replies!

Firstly I attached a picture of the bottom side of the scope. It sounds like I might be missing a rather important lens at the bottom? There are just the 2 small lenses nothing across the entire bottom if that should be there.

If I look through just the lens with a complete eyepiece my vision is "full" (I do not see a lot of black nothing). However, I can not get anything in focus even at minimum zoom and maximum distance (the scope is probably a foot in the air and I can barely distinguish the gaps in my fingers things are so zoomed in and blurry). I think that might be because the eye pieces I have are 10x zoom and so 10x*4.5x is just to much zoom to get focus. I'm guessing this is part of why you want a barlow lens. The eye piece measure at 30mm so is there an eyepiece version which does not do 10x zoom but still gives me the full work area or what is recommended here?

As for where I got the microscope sadly someone in my extended family passed away and I was responsible for figuring out what electronics were worth keeping/selling. With limited time for cleanup I grabbed all I could find for his microscope but knew I was missing parts.

As for my experience I use microscopes at work on the semi regular but usually in labs where someone has already set them up and I just need to get things in focus. So I don't really know all the parts to one. I can turn the knobs to get focus with a properly equipped scope but obviously things are missing here and I wasn't sure which things were causing me issues.

[thm_w]

Firstly I attached a picture of the bottom side of the scope. It sounds like I might be missing a rather important lens at the bottom? There are just the 2 small lenses nothing across the entire bottom if that should be there.

This is normal, its not necessary to have the barlow lens at the bottom but most people do. Typical value would be 0.5x. You can read here: https://www.microscope.com/education-center/how-to-guides/barlow-lens/

You should still be able to focus the microscope with the 10x eyepieces. Bring it closer to your test object.

[arduic]

Ah you were right if I brought it really close it finally would come into focus. The size of what I was looking at was much smaller then what I was used to which I guess is due to the lack of the barlow.

Seems I will get some new eyepieces and a barlow and this should all be working again. I'm fairly confident I have an SM series amscope but if anyone can find a way to determine that I would also really appreciate that.

[jfiresto]

Thank you for all the replies!

Firstly I attached a picture of the bottom side of the scope. It sounds like I might be missing a rather important lens at the bottom? There are just the 2 small lenses nothing across the entire bottom if that should be there.

Thanks for the picture. I don't have your microscope, but that looks like the typical (complete) objective pair of a Greenough design. When I brighten the image to a step shy of oblivion, I believe I can see inner threads in the outer, round housing, which a barlow lens ("auxiliary objective"), mentioned above, would screw in to. Your microscope at work may be a Common Main Objective design which would present a single, large lens spanning the bottom.

There is a little song and dance to make a microscope parfocal, that is, stay in focus as you zoom in and out. A lot of things should just work once you have done/achieved that.

Do you wear glasses when you use your microscopes? I could recommend an eyepiece pair, I purchased a couple months ago, if you do.

[arduic]

I have never used glasses while working on a microscope but I've also never had the option for that to work. Not sure I would buy them but always happy to know of options.

[jfiresto]

I think I did not phrase that quite right. If you are looking for a pair, I can point you toward a competent Chinese copy for sale on ebay.com of a Zeiss eyepiece. They might need deeper eye cups to use without glasses.

You might be surprised by what more you can see with glasses and a pair of eyeglass-friendly (high eyepoint) oculars. Your eyes may have slowly developed the need for a significant cylinder correction, as happened to me. For a while, I just could not get the full resolution out of a microscope I knew it could give, until I realized the problem was not in the optics of the instrument but the observer.

[thm_w]

I prefer non-eyeglasses use seems easier to get better FOV, but I don't have astigmatism (CYL), so maybe that is the key difference.