MicrobeHunter.com Microscopy Forum

Yours should have a spring action. It can be stuck from being dropped and the shell slightly deformed, corrosion, immersion oil dried, or attempts to lube it followed by oxidized oil. I believe there are past posts on how to unstick it. The good news, for now, is that yours appears to be stuck in th...

FWIW, you could think of focusing range from the parfocal tip of the objective down, as well, since the stage is most commonly the part that moves up and down in today's compound scopes. Many scopes have an adjustable stage stop to avoid crashing a slide into the objective when it's being raised - a...

I'm not sure I'd trust today's low-end makers to use the term "fine focus range" in the way it was once understood. Those ranges (25mm or 30mm) sound like coarse focusing ranges. It may also be the fine focusing range, depending on the mechanism. That is, how much room there is from focusing from th...

My guesstimate is that the three likeliest problems are: 1) Inability to get both good Kohler illumination and a wide enough image circle. One would expect color fringing at the very edges of the illuminated field, but with that mostly outside the field of view with a proper illumination system, the...

Was it a DIY or commercial LED retrofit? I've had good luck with Saul's units and also the RetroDiode.

Two of your problems may have more to do with your condenser than the objectives. 1) The 4x objectives, and particularly the 4x CFN .13 n.a. should easily fill a 20mm FN IF you have a suitable condenser - such as the Nikon flip top unit, with the top down. You can also try dropping your condenser if...

Their distributor's websites in Thailand and Vietnam:

https://www.shodensha.co.th/en/
https://www.shodensha.com.vn/en/company/

I'd be curious to know if Shodensa makes its own line of Japanese stereo microscopes or if the OEM business is mostly vision systems?

It's possible, but as suggested above, probably not worth the additional cost and effort. What you would need to do is purchase a set of infinity objectives, purchase a compatible infinity head and eyepieces, and then make a dovetail adapter so the new infinity head and its tube less fit your existi...

Stjepo, FWIW, the white dot in your photo, if repeated three times around the barrel, is likely the elastomer mentioned earlier. Digging that out may help free the entire front lens assembly. At this point, rescuing this objective is a testament to your patience and ingenuity. Don Quixote would be i...

I am your man . . . Hope you let us know if it manages to improve things. Civilization is made with courageous pioneers like you :-) - both what works and what doesn't. Two thoughts, probably both of which you know. First, make sure the objective barrel is suspended in the cleaner, rather than rest...

Stephen, were all or most of his images taken with the AO setup? If so, glad to see them put to such amazing use.

If you happen to have access to a lathe, another option is to mount the objective in an RMS extension, hold that extension in a collet (or chuck if you're super careful and have a long RMS extension), and then use very fine (600 grit or so) silicon carbide paper. It's easily controllable, quick, and...

Hi Tim, You'd probably be disappointed with the resolution of HMC at 100x -- and in any case, those objectives seem to be rare on the used market. It's typically used on inverted scopes, up to 40x objectives. The company did make some at 100x, though. It sounds like you're on to something with getti...

As said above, Hoffman Modulation Contrast is a good option for birefringent objects. The objectives seem to show up fairly frequently and moderately priced (around $100-$150 for 20x or 40x with correction collars). The condensers are harder to find, but a DIY addition of polarizing sections to clea...

Removing the front element(s) is often the most difficult part. Sometimes a "lens sucker" can help if the lens isn't cement or stuck in place. Since the objective is likely a goner anyway, you could also try further loosening the seal at the front and then pushing it out through the tube. That could...

Thanks for sharing those wonderful images, Bruce.

Might also be part of some version of Nikon's 35mm camera apparatus - used to view and achieve accurate focus. Similar, perhaps, to this:
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There are three pretty noticeable differences with the better quality Nikon CFI 160 (say, Plan Fluor) or Leica DM (say, again, Plan Fluor or up) objectives with 25mm threads. First, they have excellent contrast wide open. Second, you can get a better tradeoff between resolution and contrast (by adju...

I'm not entirely clear what the problem is. The 60x Plan Apo pictured on the right has the same wider front element as the one I own. I'd have to check in storage if the 100x Plan Apo also looks right. Have you checked the actual magnifications with a slide micrometer? Is the labelled 100x actually ...

. . . I read this pdf, and then put in a diffuser like this, the image quality is much improved, but i'm not sure if that's the right place. [/quote] You'll want the diffuser after the heat filter (and the Optiphot already has a place for it). At some point it may suffer thermal shock and crack if p...

+1 . . . Spectacular - as are the other two postings.

In addition to the gooseneck LED lamps, I'll use LED flashlights held in stands or on articulating arms. The ones with the 18650 lithium-ion batteries are bright, dimmable, and last a long time before needing a recharge. They're easily positioned from near vertical to raking angles. Multiple sources...

I'd guess that something was lost in translation.

Perhaps, along the lines of: this won't be have any better resolution of a dry .70na objective used with exactly .17mm cover slips. But, if your cover slips are thinner or thicker, this will let you get them in sharp focus.

The iris would be useful in darkfield and the objective might be less sensitive to coverslip variations without messing with a correction collar. For brightfield, I'd expect images at 1.00na to be a noticeable step ahead of the dry objective. Also, given the close working distances, this is a 40x yo...

Nikon offers a few different options, ranging from no camera port on the basic stand, to a single trinocular head, to teaching intermediates, and a dual port version as you apparently have. It would be useful if you wanted to connect a still camera and a movie camera at the same time. For surgical s...

An inverted scope makes sense if you want access to your specimens. Examples would be electrophysiology experiments, plucking critters up with a pipette, and most anything you'd want to mess with in a Petri dish. Because the stage is at a fixed height, it's also ideal for adding micro-manipulators, ...

There's a US eBay seller laser cutting various phase annuli out of Delrin. The smallest ones have slightly fuzzy edges, but overall, it's a good solution. Another approach is to use watch crystals, black vinyl, and one of the fairly precise China-made circle cutters - I believe someone posted a link...

Your DMRE is potentially a marvelously capable microscope. And, the worst case for the lamps isn't so bad. If the problem turns out to be more than a burnt lamp or fuse, a loose wire, or just not understanding which switch switches what -- you could simply get an external 100 watt power supply (ofte...

While I'm not a fan of Facebook, there's little risk in just visiting the site -- and the linked image of neurotransmitters is pretty cool. The hidden spam links that creep into many newbie posts are another matter. Sabatini, however, is a trusted (at least by me) long-time poster. In this case, SS,...

Excellent, Francisco - and almost single-celled humorous. That ciliate looks like me wandering around our kitchen before a cup of coffee.

Can you tell us how you captured that? It looks like there's a bit of oblique light coming in.