Whats the best way to look at an awkward object using the 40x lens without damaging it

[JCTyler]

I've got what seems to be a Chinese clone of an Olympus microscope. I'm trying to inspect a record player needle with it. When I set it for the 40x lens, its touching the needle which is what I don't want.I know it needs to be placed very close to the subject to view the detail. I tried with a piece of aloe vera plant in a slide and it worked fine. Is there a way to prepare a custom slide to view it without damaging it or perhaps unscrew the stage and support the needle from the plastic base with a Helping Hand with alligator clips?

[BramHuntingNematodes]

Olympus has had several lines of lwd metallography objectives you could look into. The standard 40x achromat wants a cover glass and to be very close to it as well.

[dtsh]

Ideally you'd want to use objectives designed for use without a coverslip. Working distances are typically small with a 40x objective, often around 0.5mm. You could try placing it on a slide and getting it centered, but you'll probably need to illuminate it from the side, which at that working distance might be frustrating.
If I were trying to do it, I'd probably glue, tape, or putty the needle to a slide so that it's oriented in the direction needed and try using an illuminator angled in from the side. I would likely try to use a 20x objective and 15x eyepiece, not the same 400x, but 300x with a significantly increased working distance and depth.

[PeteM]

FWIW, I believe the condition of phono needles is generally done with a stereo microscope, which have much larger working distances. It's also done - at least by the two enthusiastic record collectors I know - at more like 40-60x total magnification. With a 40x objective, a compound microscope, and 10x eyepieces you're up around 400x. More than is likely needed to see wear. Maybe not more than needed for your application?

[JCTyler]

I finally figured out what I've got; its this. Seems to be a Russian/Chinese clone. Does anyone know where I can get the manual for it? I found a similar Soviet era clone that uses RMS thread. Would the xsc-04 use RMS thread for its objectives too?


https://www.easyliveauction.com/catalog ... l-lot-311/

[JCTyler]

Ideally you'd want to use objectives designed for use without a coverslip. Working distances are typically small with a 40x objective, often around 0.5mm. You could try placing it on a slide and getting it centered, but you'll probably need to illuminate it from the side, which at that working distance might be frustrating.
If I were trying to do it, I'd probably glue, tape, or putty the needle to a slide so that it's oriented in the direction needed and try using an illuminator angled in from the side. I would likely try to use a 20x objective and 15x eyepiece, not the same 400x, but 300x with a significantly increased working distance and depth.

I tried some bluetac for putty and a luxo lamp bent to provide light from the side. I got a good image with a 10x objective and a 12.5x eyepiece. I'll have to source a 20x objective.

[apochronaut]

I finally figured out what I've got; its this. Seems to be a Russian/Chinese clone. Does anyone know where I can get the manual for it? I found a similar Soviet era clone that uses RMS thread. Would the xsc-04 use RMS thread for its objectives too?


https://www.easyliveauction.com/catalog ... l-lot-311/

That is a Chinese basic lab microscope from likely, the 1960's. It's not really an Olympus clone. There were dozens of brands of horseshoe based microscopes that look very similar and each used a certain parfocal length of objective, ranging from 25mm for smaller hobby type scopes to 45mm. Olympus originally either copied or assembled Leitz lenses in Japan that were 37mm parfocal but changed to a copy of Bausch & Lomb during the Occupied Japan era. Those were 36.65 mm for about 30 years, then they changed to the D.I.N. standard of 45mm parfocal.
In China they used a 35mm parfocal mostly, switching in the 70's or 80's mostly to 45mm. They still use shorter objectives for some student microscopes. In China they are known as a 185mm system, while the longer 45mm objective is in a 195mm system.
Here is a 20X Chinese 185mm system objective that should be fairly close to being parfocal with yours.
https://www.ebay.com/itm/144555578645?h ... SwvPxigQPs.