Search found 33 matches
- Fri Feb 17, 2023 11:55 am
- Forum: Specimens, samples and slides
- Topic: Making tardigrades opaque
- Replies: 3
- Views: 1267
Making tardigrades opaque
Hello! Is there a cheap and simple way to make tardigrades' surface opaque, so that cuticle morphology can be easily observed, obtaining images somewhat similar to SEM electron microscopy? In principle, I could use vacuum sputter coaters that deposit gold or palladium or carbon on samples for SEM. B...
- Thu Aug 18, 2022 2:02 pm
- Forum: Microscopes and optics
- Topic: Magnification of 160 mm Seidentopf bino-heads
- Replies: 1
- Views: 565
Magnification of 160 mm Seidentopf bino-heads
Hi all, I'm wondering what is the magnification factor of twist-type (Seidentopf) bino heads on 160 mm microscopes? Or rather, are there any 1.0x heads of this type? The optical path length on these looks outwardly to be so much longer than on slide-type (Jentsch) heads that it can't possibly keep t...
- Thu Jul 07, 2022 4:03 pm
- Forum: Microscopes and optics
- Topic: ED low-dispersion glasses
- Replies: 3
- Views: 1284
ED low-dispersion glasses
In amateur astronomy, one can now buy a 100 mm diameter objective employing "ED" (extremely-low dispersion) glass as one of the doublet's lenses, plus the optical tube and focusser, for about 800 EUR (ordinary achromatic doublet costing 1/3 of that). It offers massive improvement in chromatic aberra...
- Thu Jul 07, 2022 1:58 pm
- Forum: Home-made microscope adaptations
- Topic: DIY epi-illumination through eyepiece port
- Replies: 4
- Views: 2471
DIY epi-illumination through eyepiece port
Since used Nikon epi-illuminators are unfortunately too expensive for my budget, I was thinking of using one of the eyepiece ports of my Nikon YS2-H's bino head as an illumination port (with LED). But the reflection of the illuminating beam on the beam-splitter face drowns out the image coming up fr...
- Sun Jul 03, 2022 5:26 pm
- Forum: Microscopes and optics
- Topic: Assembling iris
- Replies: 18
- Views: 2970
Re: Assembling iris
I would think some ingenious tools or jigs were used for iris assembly. The "machines that make the machine" are often more interesting than the products! Regarding the iris guy or iris gal question, watchmakers used to be man, weren't they? So fine motor skills are not gender-specific. The prevalen...
- Sun Jul 03, 2022 4:51 pm
- Forum: Microscopes and optics
- Topic: Achro or plan for epi-illumination?
- Replies: 4
- Views: 1019
Achro or plan for epi-illumination?
I'm wondering which Chinese 160 mm objectives to choose for cheap epi-illumination to minimize back-reflections: achromats or planachromats? Achros have fewer lenses (less back-reflection), but planachros probably (just my guess!) have better anti-reflection coatings, since they're a higher class pr...
- Sun Jul 03, 2022 4:40 pm
- Forum: Microscopes and optics
- Topic: NIKON YS2-H
- Replies: 3
- Views: 921
Re: NIKON YS2-H
My YS2-H also has this problem, in addition to the lamp changing brightness on its own randomly. I'm going to change the lamp first, as it's old and the manual suggests it might be a symptom of the lamp approaching failure. Lamp is about $ 2 in my country.
I wish you good luck with your scope!
I wish you good luck with your scope!
- Sat May 28, 2022 12:25 pm
- Forum: Microscopes and optics
- Topic: Meaning of "O" eyepiece designation
- Replies: 1
- Views: 597
Meaning of "O" eyepiece designation
Hi, I have a pair of eyepieces made by Meopta Czechoslovakia in the 1960s (?) labeled "O 10x". Would someone happen to know what the letter O could mean? Other eyepieces Meopta made are obvious - H for Huygens, K for compensating, P for projection or photographic or maybe periplan. Meopta used to be...
- Fri May 27, 2022 6:06 pm
- Forum: Illumination Techniques
- Topic: LED lighting....why the hate?
- Replies: 72
- Views: 14865
Re: LED lighting....why the hate?
80lm/W instead of 160lm/W sonds quite ok, no reason not to use it for this application. At 2700K it might be a bit yellowish for a nice visual impression, but this is personal taste. This might be a good place to mention that the highest theoretical efficiency for making warm white light with a LED...
- Fri May 27, 2022 4:14 pm
- Forum: Illumination Techniques
- Topic: LED lighting....why the hate?
- Replies: 72
- Views: 14865
Re: LED lighting....why the hate?
Sorry, I am not clever enough to explain this diagram succinctly . 5E5452B7-EAD6-49FE-8D28-40FBE176A308.jpeg . MichaelG. It says that some leds you get will be pinkish, some greenish, and if you pay premium you can get the whiter ones (bins), those near the white curve that goes from left to right....
- Fri May 27, 2022 3:18 pm
- Forum: Illumination Techniques
- Topic: LED lighting....why the hate?
- Replies: 72
- Views: 14865
Re: LED lighting....why the hate?
… if we can identify the chip manufacturer, the should be available [somewhere] on a reel The search is on !! Look, the EMOS bulbs are available on German Amazon! I thought EMOS only sells in Czech Republic. https://www.amazon.de/Colour-Rendering-Replaces-Neutral-Lifespan/dp/B07YNVJX7X?ref_=ast_sto...
- Fri May 27, 2022 2:15 pm
- Forum: Microscopes and optics
- Topic: Kid's/student's objective standard?
- Replies: 11
- Views: 2638
Re: Kid's/student's objective standard?
That giant 63x objective is really RMS/DIN? :) It dwarfs the entire microscope... The bulkiness of today's objective bodies hides the diminutivness of the lenses inside... Altogether, I feel awe and respect. The hardwood case indicates how laborious and expensive it was to do even a toy/hobby micros...
- Thu May 26, 2022 8:16 pm
- Forum: Illumination Techniques
- Topic: LED lighting....why the hate?
- Replies: 72
- Views: 14865
Re: LED lighting....why the hate?
That is a nice spektrum, jjtr1! If this is from a single die it would be very interesting to investigate further. Many microscopes don't have a true Köhler setup but a frosted lens in the light path that acts as the light source. In this case multiple LED dies could be used. Colour enlargers used t...
- Thu May 26, 2022 7:00 pm
- Forum: Illumination Techniques
- Topic: LED lighting....why the hate?
- Replies: 72
- Views: 14865
Re: LED lighting....why the hate?
Nice spectrum, but certainly that spectrum is not produced by a single die, or even a single COB led. It is probably produced by a combination of many different LED dies. For microscopy, we need a single die, or a fairly small COB led. The Yuji and Optosolis COB leds are the closest thing that I've...
- Thu May 26, 2022 4:16 pm
- Forum: Illumination Techniques
- Topic: LED lighting....why the hate?
- Replies: 72
- Views: 14865
Re: LED lighting....why the hate?
An unfortunate aspect of cheap led illumination systems is the loss of information due to the limited number of spectral lines that they produce. The eye has evolved to utilize the full spectrum of daylight in order to be provided with the maximum amount of information available and while no artifi...
- Wed May 25, 2022 8:59 pm
- Forum: Beginner's corner
- Topic: Viewing DVDs
- Replies: 4
- Views: 1359
Re: Viewing DVDs
About 8:30 into this : https://www.youtube.com/watch?v=GuCdsyCWmt8 (peeled it off with sticky tape). :-D Sticky tape for CDs and Xacto knife for DVDs. Sometimes brute force wins over fine optics :) I might try that. I was wondering that maybe if I shortened the optical tube, I could extend the work...
- Wed May 25, 2022 12:00 pm
- Forum: Microscopes and optics
- Topic: Kid's/student's objective standard?
- Replies: 11
- Views: 2638
Re: Kid's/student's objective standard?
There was a sort of standard developed by the manufacturers of toy/hobby microscopes from the 50's onward in Japan, sold widely through dept. stores. Objective thread was normally hitched to the size of the body of the scope and that was hitched to it's magnification. 300X, 450X, 600X, 750X, 900X, ...
- Wed May 25, 2022 11:41 am
- Forum: Microscopes and optics
- Topic: Kid's/student's objective standard?
- Replies: 11
- Views: 2638
Re: Kid's/student's objective standard?
I don't know if these are of any interest to you. I ran across them on ebay while looking for a 100x oil objective. They are 15mm mount. Those are exactly my little scope's objectives :) Ufortunately, no 20x is on sale. But I have at least found this old 15 mm set with engraving instead if printing...
- Sat May 21, 2022 4:41 pm
- Forum: Beginner's corner
- Topic: Viewing DVDs
- Replies: 4
- Views: 1359
Viewing DVDs
Hi, I'm wondering if there is a cheap way of viewing the pits and lands of a DVD disc. The problem is that the data layer is buried 0.6 mm below surface. 40x objective usually doesn't have sufficient working distance. Is there a way other than buying an expensive LWD objective? DVD, CD and Blu-ray p...
- Sat May 21, 2022 8:08 am
- Forum: Microscopes and optics
- Topic: Kid's/student's objective standard?
- Replies: 11
- Views: 2638
Re: Kid's/student's objective standard?
Greg, thank you for the info! The 4x and 10x are usable (within say 12 mm field), but the 40x is junk (even with the illuminator (also junk) fixed to fill the 40x's aperture). 40x is probably too demanding for the substandard manufacturing, but 20x could be ok. PeteM, I also have a Nikon Alphaphot-2...
- Fri May 20, 2022 5:31 pm
- Forum: Microscopes and optics
- Topic: Kid's/student's objective standard?
- Replies: 11
- Views: 2638
Kid's/student's objective standard?
Hi, the objectives on my student's microscope (not a toy, but very short - just 25 cm) are not RMS nor DIN - the thread is 15 mm dia. and parfocal distance is 32 mm. (Tube length is hard to measure because of the 45 deg. prism.) Would someone happen to know whether this was some antique objective st...
- Mon May 16, 2022 10:04 pm
- Forum: Beginner's corner
- Topic: Erecting bino heads
- Replies: 4
- Views: 1124
Re: Erecting bino heads
I imagine that an erecting head could be constructed by simply substituting the wedge prism that tilts light path by 45 deg. with a roof prism (Schmidt-Pechan prism pair, as in straight binoculars, but without the wedge part). It would add about 20-30 mm to the light path. https://en.m.wikipedia.org...
- Mon May 16, 2022 8:30 pm
- Forum: Beginner's corner
- Topic: Erecting bino heads
- Replies: 4
- Views: 1124
Erecting bino heads
Hi,
do erecting binocular heads (i.e. ones that provide non-inverted image) for microscopes (not stereoscopes) exist? Why aren't they more common? Are they possible with 160 mm finite systems (light path inside the erecting prism(s) might be too long)?
Thank you for your answers
do erecting binocular heads (i.e. ones that provide non-inverted image) for microscopes (not stereoscopes) exist? Why aren't they more common? Are they possible with 160 mm finite systems (light path inside the erecting prism(s) might be too long)?
Thank you for your answers
- Mon May 16, 2022 8:04 pm
- Forum: Microscopes and optics
- Topic: Intriguing objective design (Nikon CF 40x achro)
- Replies: 32
- Views: 7699
Re: Intriguing objective design (Nikon CF 40x achro)
More of a thick meniscus lens. The design's first iteration was probably this Zeiss patent from 1938 invented by Hans Boegehold. It shows up as a scattered design feature until the 70's, afterwhich it was widely used by at least 5 mfg. I can think of during that decade. https://patents.google.com/p...
- Mon May 16, 2022 7:54 pm
- Forum: Microscopes and optics
- Topic: Intriguing objective design (Nikon CF 40x achro)
- Replies: 32
- Views: 7699
Re: Intriguing objective design (Nikon CF 40x achro)
jjtr1, does the rear element of your objective appear to have a concave surface (and appear to be made out of a thick slug of glass) ? ....a bit like the PlanAchro's in abednego's illustration. The rear lens of my 40x is concave and lies right at the end of the barrel, as in NCF PlanAchro. Hard to ...
- Sun May 15, 2022 9:08 am
- Forum: Microscopes and optics
- Topic: Intriguing objective design (Nikon CF 40x achro)
- Replies: 32
- Views: 7699
Re: Intriguing objective design (Nikon CF 40x achro)
Nice observation. That 40x objective at NA0.65 wouldn't require a embedded first element as used in high NA objectives (i.e. NA1.40), so it is made to be concave at the first surface and isn't missing anything. The surrounding donut of frosted glass should have been initially blacked out with a thi...
- Fri May 13, 2022 10:42 pm
- Forum: Microscopes and optics
- Topic: Intriguing objective design (Nikon CF 40x achro)
- Replies: 32
- Views: 7699
Re: Intriguing objective design (Nikon CF 40x achro)
I'm afraid I don't know the answer to your question. It may be there's a metal annulus behind the front lens? Also, I'm not sure that it's strictly a CF lens. I've seen a number of lenses around (some very cheap) that are marked as Nikon and are finite 160mm RMS. Many are contemporary e.g. https://...
- Fri May 13, 2022 4:52 pm
- Forum: Microscopes and optics
- Topic: Intriguing objective design (Nikon CF 40x achro)
- Replies: 32
- Views: 7699
Intriguing objective design (Nikon CF 40x achro)
Hello, I'd like to share here an intriguing design of the first lens of my Nikon CF 40x achromatic finite objective (1990s). The tiny lens, instead of being mounted in a metal tube, seems to be mounted in an annulus of ground or frosted glass representing most of the objective's front end area. Pict...
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- Fri May 13, 2022 4:12 pm
- Forum: Microscopes and optics
- Topic: Do Chinese noname Plan objectives need compensating eyepieces?
- Replies: 9
- Views: 1867
Re: Do Chinese noname Plan objectives need compensating eyepieces?
I may be wrong but I think Jena was still using an achromat : correcting eyepiece and apochromat : compensating eyepiece system. Systems adopting a compensating condition for both arrived on a staggered basis mfg. by mfg. from the 60's onward. AO were the first or at least one of the first to harmo...