Search found 2963 matches

by PeteM
Mon Mar 18, 2024 7:37 pm
Forum: Miscellaneous
Topic: The Place of Value in a World of Fact
Replies: 2
Views: 102

Re: The Place of Value in a World of Fact

There's a huge literature on consciousness - which is somewhere between a twin to a kissing cousin to awareness. Julian Jaynes thought we didn't become conscious until 3000 years ago (Origin of Consciousness in the Breakdown of the Bicameral Mind). However, more recent research with primates shows t...
by PeteM
Sat Mar 16, 2024 4:53 am
Forum: Beginner's corner
Topic: unmarked long silver objective lens?
Replies: 1
Views: 158

Re: unmarked long silver objective lens?

The objective is missing its outer shroud, which would have had the markings. Just guessing from the Nikon turret and the size of the visible lens, I'd guess that it's a Nikon finite objective around (+/-) 10x. It will work without the shroud and it should be possible to figure the magnification eit...
by PeteM
Fri Mar 15, 2024 3:06 am
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 546

Re: Reichert U.S.A. and Leica. Why the undercorrection?

"I would be interested to know if anyone has used a Reichert Austria objective in a Delta based stand" Here's a quick test using a Delta-era Leica 501055 head with L Plan 10x/20 eyepieces. The stand is a DMLS that just came in. It has a yellow hot spot in the illumination—maybe the wrong bulb or ill...
by PeteM
Thu Mar 14, 2024 7:22 pm
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 546

Re: Reichert U.S.A. and Leica. Why the undercorrection?

Here's a shot at summarizing the discussion of eyepiece corrections in a table. There are surely omissions and likely errors. Let me know and I'll update it.

.
AO, Reichert, Leica eyepiece corrections.png
AO, Reichert, Leica eyepiece corrections.png (259.07 KiB) Viewed 277 times
by PeteM
Thu Mar 14, 2024 4:02 am
Forum: Beginner's corner
Topic: What happened to the Leica DMLB?
Replies: 8
Views: 400

Re: What happened to the Leica DMLB?

As you say, US trade policy certainly played a role in the decline of some US companies—as did the internecine battles Wayne covers and a switch from engineers running these companies to financial folks looking for a quick buck as they bought up companies, mashed them together, slashed resources, an...
by PeteM
Wed Mar 13, 2024 10:24 pm
Forum: Beginner's corner
Topic: What happened to the Leica DMLB?
Replies: 8
Views: 400

Re: What happened to the Leica DMLB?

Sad to say, support for legacy products is poor to abysmal in the microscope world. Vendors want you to buy new, rather than bring older ones back to life. In fact, some have threatened to sue for copyright infringement when hobbyists post older manuals with still-active copyrights. Under recent law...
by PeteM
Wed Mar 13, 2024 5:50 am
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 546

Re: Reichert U.S.A. and Leica. Why the undercorrection?

I was thinking it more a matter of production costs - that they might be able to use some existing designs, machines, or processes. It's purely conjecture. Someone intimately involved would know better if any IP, factory preferences, production processes, or machinery carried over. Don't know Leica'...
by PeteM
Wed Mar 13, 2024 4:13 am
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 546

Re: Reichert U.S.A. and Leica. Why the undercorrection?

I've never seen an explanation of this, but I can offer a hypothesis. The buyout occurred at an early time of financiers buying up companies and trying to assemble mini-conglomerates. That sort of management would very likely have wanted to invest as little as possible in R&D. Thus, bringing forward...
by PeteM
Wed Mar 13, 2024 1:19 am
Forum: Beginner's corner
Topic: What happened to the Leica DMLB?
Replies: 8
Views: 400

Re: What happened to the Leica DMLB?

To add, prior to Danaher buying Leica, the company was a tortured tale of mergers with remnants of Spencer, American Optical, Bausch & Lomb, Cambridge Instruments, Jung, Leitz, and Reichert in the mix. Several threads on Microbe Hunter touch on various aspects of this. While many of these companies ...
by PeteM
Wed Mar 13, 2024 12:52 am
Forum: Beginner's corner
Topic: What happened to the Leica DMLB?
Replies: 8
Views: 400

Re: What happened to the Leica DMLB?

The DME, DMLS, and DMLB has been replaced by a series of DM (Das Mikroskop) models along the lines of DM300, DM500, DM750, DM1000, DM2000, DM2500, DM3000, DM4000 etc. The low-end models, say up to about DM750, are pretty mundane educational models. You might as well buy any similar Chinese scope. Th...
by PeteM
Tue Mar 12, 2024 4:14 am
Forum: Microscopes and optics
Topic: Microscope storage/portability options
Replies: 4
Views: 491

Re: Microscope storage/portability options

A lot depends on whether you will be carrying this about by yourself (and avoid dropping or tossing it from, say, a truck liftgate) -- or intend to hand it off to Fed Ex Ground paid-by-the-second drivers, airport baggage handlers, and the like. There are dozens of affordable alternatives in the firs...
by PeteM
Thu Mar 07, 2024 11:32 pm
Forum: Microscopes and optics
Topic: Olympus CX43 any thoughts ,made in China apparently
Replies: 19
Views: 746

Re: Olympus CX43 any thoughts ,made in China apparently

I took a look at eBay.au and see what you mean, Cliff. There's not much available and the shipping cost for the US-listed ones is very high. One possible avenue would be to look for a bare stand in Australia (the heavy and bulky part) and keep an eye out for objectives and eyepieces from elsewhere. ...
by PeteM
Thu Mar 07, 2024 4:39 am
Forum: Microscopy accessories
Topic: 1/4 wave filter source
Replies: 12
Views: 1479

Re: 1/4 wave filter source

JWWW -- nicely done and illlustrated - thanks for the post.

Which of the quarter wave plates did you choose (glass high performance?) and are you happy with it? Also curious if you went larger than 50mm and the cost?
by PeteM
Thu Mar 07, 2024 4:31 am
Forum: Microscopes and optics
Topic: How to use the AO10 Teaching Head
Replies: 9
Views: 365

Re: How to use the AO10 Teaching Head

Bruce, you're likely referring to the pointer available in some AO teaching heads. It allows an instructor to place an arrow at some point of interest in the visual field; and requires a cord and an external power supply to light it up. P.S. Neeley's "Xmission" website will likely have documentation.
by PeteM
Thu Mar 07, 2024 1:49 am
Forum: Microscopes and optics
Topic: Olympus CX43 any thoughts ,made in China apparently
Replies: 19
Views: 746

Re: Olympus CX43 any thoughts ,made in China apparently

If the Nikon is that far out, it's because it's the wrong generation of objective. If you focus your 100x or 40x objective on a slide - and measure the distance from the lens turret to the slide, the newer finite objectives (DIN standard) will be around 45mm. Just the distance from the shoulder of a...
by PeteM
Thu Mar 07, 2024 12:11 am
Forum: Microscopes and optics
Topic: Olympus CX43 any thoughts ,made in China apparently
Replies: 19
Views: 746

Re: Olympus CX43 any thoughts ,made in China apparently

Cliff, FWIW, you can buy parfocal shims to get the objectives on a turret all at about the same focus. These are basically thin washers ranging (US) from about .002 up in thousandths increments. It's rare to find a mix of different objectives parfocal, even if they are all 45mm (DIN standard) parfoc...
by PeteM
Wed Mar 06, 2024 4:40 pm
Forum: Microscopes and optics
Topic: Olympus CX43 any thoughts ,made in China apparently
Replies: 19
Views: 746

Re: Olympus CX43 any thoughts ,made in China apparently

Cliff, the point about the Aussie sellers on eBay is that you could probably contact them directly. "Micrographix" in particular has been a helpful and trusted source. If you're looking for phase contrast, you might also consider a used Zeiss "Standard" as well as Olympus BH2 and Nikon Labophot and ...
by PeteM
Wed Mar 06, 2024 4:56 am
Forum: Microscopes and optics
Topic: Olympus CX43 any thoughts ,made in China apparently
Replies: 19
Views: 746

Re: Olympus CX43 any thoughts ,made in China apparently

Cliff, there are at least a couple of Australians who sell on US eBay - at least one with reasonable prices. Perhaps one of them can help you find a good used scope?

You'd be paying a premium for the Olympus name. If buying new, I'd suggest something like the Motic equivalent, shipped from China.
by PeteM
Tue Mar 05, 2024 6:57 am
Forum: Microscopes and optics
Topic: Polylite SC endusers(?)
Replies: 39
Views: 1320

Re: Polylite SC endusers(?)

JWW - I'm not sure how much, if anything, is common in photo relay lenses between Leica DM systems and your Polylite. That said, the Leica's generally use an 8x (or sometimes 10x) photo relay lens (with the proper corrections) combined with a .32x lens further up in the optical train near a full fra...
by PeteM
Mon Mar 04, 2024 1:33 am
Forum: Beginner's corner
Topic: Newbie buying first microscope
Replies: 14
Views: 752

Re: Newbie buying first microscope

Depending on your location, there's likely a microscope group or a respected hobbyist willing to lend you a hand. There are dozens of potentially excellent microscopes in your upper price range. Along with Olympus BX models, I'd include Nikon Eclipse and Leica DMLB or DM2000 and above. I'm less keen...
by PeteM
Sun Mar 03, 2024 10:51 pm
Forum: Microscopes and optics
Topic: Polylite SC endusers(?)
Replies: 39
Views: 1320

Re: Polylite SC endusers(?)

Dang, JWW. Now I have Polylite envy . . . :-)
by PeteM
Sun Mar 03, 2024 10:46 pm
Forum: Beginner's corner
Topic: Newbie buying first microscope
Replies: 14
Views: 752

Re: Newbie buying first microscope

For less than the price of that used $2500 Olympus CX microscope (from a dealer?), you might look for a used Olympus BX in excellent condition, It would be a more expandable microscope, hold its value better, and possibly be equipped with significantly better plan fluorite objectives or other featur...
by PeteM
Sat Mar 02, 2024 6:11 pm
Forum: Pictures and Videos
Topic: The Much Underestimated Celery Stalk
Replies: 2
Views: 135

Re: The Much Underestimated Celery Stalk

Your titles always bring a smile, Don. And, who knew . . . it's the Brock Purdy of vegetables. Drafted last into the shopping cart, but a star leading the way under the microscope. Sadly, though, just missing winning this year's Super Salad Bowl.
by PeteM
Sat Mar 02, 2024 7:37 am
Forum: Microscopes and optics
Topic: Selling old Leitz Laborlux or SM?
Replies: 20
Views: 734

Re: Selling old Leitz Laborlux

The cap will help you get a quicker sale, towards the higher end of the range. As Alexander says, the value is in the condenser - which you might sell separately.
by PeteM
Sat Mar 02, 2024 7:24 am
Forum: Microscopes and optics
Topic: Selling old Leitz Laborlux or SM?
Replies: 20
Views: 734

Re: Selling old Leitz Laborlux

Nice looking scope. It does have the Heine condenser, missing it's top oil lens, as noted above. The dry darkfield condenser is also useful. Depending upon the objectives (plan? phase? fluorite? apo?), I'd think it would be worth $700-800 plus or minus to the right buyer; possibly to someone here. Y...
by PeteM
Sat Mar 02, 2024 7:09 am
Forum: Microscopes and optics
Topic: GF Planachromat infinity optics for Jenamed microscope
Replies: 9
Views: 407

Re: GF Planachromat infinity optics for Jenamed microscope

Pretty much. I used an M25 thin spacer and a tube cut to CFI60 parfocal length, epoxied to the Jena objective. I've just used it casually for smears and it looks, visually, OK. Haven't taken photos or done any serious comparisons to see how the corners hold up. I'd think, for APS-C, they'd be decent...
by PeteM
Sat Mar 02, 2024 4:48 am
Forum: Microscopes and optics
Topic: GF Planachromat infinity optics for Jenamed microscope
Replies: 9
Views: 407

Re: GF Planachromat infinity optics for Jenamed microscope

FWIW, I adapted a Jena GF infinity zero cover 50x to Nikon infinity (25mm thread, 60mm parfocal). It does an OK job with smears (blood, chemical crystals, etc.) and no cover slip.
by PeteM
Wed Feb 28, 2024 5:45 pm
Forum: Microscopy accessories
Topic: 1/4 wave filter source
Replies: 12
Views: 1479

Re: 1/4 wave filter source

Hi did have a 50mm or so wave filter, a while back. Techno is a good and reliable seller IMO, but in this case the wave filter had a significant defect - a sort of square (machine-made) defect that showed up when imaged between polars.
by PeteM
Wed Feb 28, 2024 4:48 am
Forum: Pictures and Videos
Topic: Pictogram or ...
Replies: 1
Views: 199

Re: Pictogram or ...

That's interesting, Saul - crystals that mostly walk straight and narrow.
by PeteM
Tue Feb 27, 2024 11:20 pm
Forum: Microscopy accessories
Topic: 1/4 wave filter source
Replies: 12
Views: 1479

Re: 1/4 wave filter source

Beautiful stages and nice work on those sliders. It might be possible to make up a sort of 60 mm OD blackened washer with about a 55 mm ID. Stretch the Edmund material flat with tape along the edges at room temperature, put a coat of plastic-metal adhering adhesive on one side of the washer (2.5mm o...