Mad Scientist Glasses

[DonSchaeffer]

Don't laugh! I bought these as an aid to dissection and specimen handling. In fact, I think they have some of the features of a stereo microscope. It includes a set of graduated magnification lenses (2.5x to 25x). Working distances do get very small at the higher power. I'm using the 2.5x lens with a 6.2 inch working distance. The 8x lens has a 2.2 inch working distance. The 25x lens (they suggest using these monocularly) has a .5 inch working distance.

By the way, what are typical working distances for stereo microscopes?

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[jfiresto]

By the way, what are typical working distances for stereo microscopes?

The microscope I am looking at has a 91mm W.D. over 6~32X which is on the low end. The W.D. is somewhat less than twice that if you add an auxiliary objective that halves the magnification.

[BramHuntingNematodes]

neat I'm always on the lookout for a good set of loupes

2 to 4 inches working distance is pretty typical for a stereo scope although this can be changed to some extent with auxiliary lenses

[jfiresto]

I wear glasses and had no luck with the Galilean loupes from Eschenbach. My eyes proved too close together for their clip-ons and my right eye's significant, but by no means enormous, cylinder correction was too much for their adjustable, prescription model. I bet Zeiss's Keplerians would be the business, but they cost more than a good, used microscope!

[DonSchaeffer]

This device is very simple or maybe primitive is the word. It does seem handy for me as I try it out. I used the 2.5 x lenses to prepare a wet mount slide this morning. I was able to clearly see and select the subject.

[jfiresto]

I bet it is pretty neat if it is like the ones I tried. If only my eyes were just slightly less off spec....

What works for me is a simple, flip down 2.5X stereo magnifier that places a simple, single-element lens before each eyeglass lens.

[PeteM]

Don - do yours have diopter adjustments for each eye? A few years ago I bought a cheap copy (maybe $150) of the type used by dentists (these have up to maybe a 20" working distance), but found them unusable because one eye was always out of focus.

Better stereo microscopes can have a wide range of working distances. Some designed for medical/surgical use may be around 12" with crisp views and a wide range of magnifications.

[DonSchaeffer]

No adjustments at all except some range of pointing direction for each lens. It cost me some $20 so I don't expect much. But it actually works pretty well.

[DonSchaeffer]

I bet it is pretty neat if it is like the ones I tried. If only my eyes were just slightly less off spec....

What works for me is a simple, flip down 2.5X stereo magnifier that places a simple, single-element lens before each eyeglass lens.

This is very similar.