MicrobeHunter.com Microscopy Forum

I am a newcomer to machine greases, for disclosure, but one thing I am wondering about is whether the PFPE oil component would creep, or not. I personally have never observed any separation of the oil in 5+ years of using PFPE-PTFE greases for just about everything I lubricate. As for whether pure ...

in my experience there is no real problem with the classic instrument lubricants, they usually last for decades and there is no dirt accumulation that really has an impact on usability. I can't say I've ever heard of petroleum greases lasting decades, even the expensive ones like nyogel. How many t...

Nice addition. Where do you get that fine PTFE powder? Cheers, John You can buy it from Chinese retailers but it's very overpriced there. They do not offer submicron sizes of powder either. I bought a 1kg sample of submicron PTFE powder from Shamrock Technologies, a US fluoroplastics company, which...

Bumping this thread to add an additional lubrication trick I've found. You know how microscope stage rails & bearings tend to collect gunk if you lube them (which compels some people to leave them un-lubed?) You can prepare a very effective dry lube, which repels gunk but keeps nice lubricity, by mi...

(...) I do have superwide eyepieces. They're amazing and totally ruined normal eyepieces for me. They almost suck you in onto the slide. But still - not big enough! :D For all of my talk of professional applications (and those really do exist IMO,) my argument ultimately comes from my amateur desir...

Wider field numbers at a given magnification have diminishing returns, and Nikon actually went down from 26.5mm to 25mm max for biological objectives. The perimeter of the eye is lower-detail, sure, but if you can handle the exit pupil I don't see how a larger field isn't significantly better (esp....

I'm curious to know in what hematology applications field width is prized over all else, including color? Counting lymphocytes and things like that. Is it really hard to envision a use case for monochromatically-driven wider fields etc. when there are certain applications of microscopes where you'r...

I think there are surely professional situations where it would make sense. Not every application is "color-sensitive." For example, in some hematology applications, field width is more desired than anything else. If there was a monochromatic microscope with 2x the field width of usual offerings, I ...

After reading about monochromatic photomicrography and its benefits, I wondered why there don't seem to be any microscopes designed from the ground up for monochromatic usage? If you only have to make a flat field for one single wavelength, and you don't need to worry about chromatic aberration at a...

Per title, what is this stuff you find on objectives? I sometimes find objectives where it's in bad shape and think about replacing it, but am not confident about what it is exactly. Liquid latex?

https://www.ebay.com/itm/363171920907 Google yields no hunch of what exactly these are. In the first image you can see they have an Olympus Japan logo. No Olympus documentation lists them, as far as I've been able to find. https://www.techeyesonline.com/measuring-device/detail/HINCD-00256-STM5-UM/ &...

That follows normal nomenclature for objectives. I don't see Olympus as doing anything any different than other manufacturers have done. I dunno. Olympus doesn't even seem consistent with themselves. For example, in the 1.35NA version of this objective, its NA is labeled on the barrel as: "1.35 - 0...

... I see. This was my intention as well, to use it mainly for high magnification darkfield (could you imagine if the 60x had an iris?) Thanks - it's encouraging to hear that this objective does indeed exist in 1.40NA +coverslip +iris flavor. It gets confusing because none of the different versions...

I was recently reviewing some of the incarnations of Splan Apo 100X that exist. There are as far as I can tell 5 or 6 total variations of this objective, having different NAs (sometimes 1.3, sometimes 1.35, sometimes 1.4) and different coverslip designations, as well as having or lacking an iris. In...

Pure PTFE is a solid until ~327 C and is practically insoluble in everything. Anything claiming to be pure PTFE and is not a solid is not pure PFTE and has a carrier in it. Yeah, the oil is PFPE and it's thickened with PTFE, my bad. In doing some research on PFPE oils today I found something intere...

Excellent stuff! I just got a 2oz tube of 206, and it works wonders. I've went as far as relubing most of my objectives with correction collars, no sticking again! (hopefully) BR, John 206 is great - IIRC it is the most popular choice in keyboards. The heavy greases are versatile. You can always di...

With infinity optics you can use a teaching bridge as a photo tube and by pass the telan lens. With an adaptor for the dovetail on the bridge( same as the head) that has a thread on the other side to fit the filter thread of a prime lens , you can use a prime lens set at infinity, mounted verticall...

I have a few different Nye synthetic lubricant products for my scopes. They seem to be well regarded but I have no long term experience yet. Nyogel - I have used it for many years. Another expensive lubricant. It is popular for flashlight threads. It eventually seems to cloud up and become not as s...

1. Proper alignment of the smartphone with the optical axis of the microscope is a time-consuming trial and error job - even with smartphone adapters; 2. The smartphone camera software is not well adept to continuous photography; 3. Zooming the phone camera each time to catch the FOV without vignet...

Since I'm going to be using all SWHK eyepieces for this, I am not sure if it actually will be afocal. They allow focal adjustment inside the eyepiece from +2 to -8 (not sure what units, but that's how it's labeled on the eyepiece.) And I'll be going for parfocality between two of them, so it's seemi...

Have a look at this link if you haven't already: http://krebsmicro.com/relayDSLR/relayoptics1.html Thanks for the link. It seems to confirm that smaller pixel size (ie. smaller sensor) is indeed better, at least for meeting the resolution requirements of low-power plan apo optics? I could be missin...

You aren't going to get great quality of imaging with a smartphone camera It should be 1000~3000% more resolution than is needed, according to https://www.youtube.com/watch?v=2JhWaMFBm4I - small-size sensors (or rather, pixels) are apparently way better for microscopy. you now see that the f.o.v. o...

Yes. a larger sensor would theoretically capture more information and therefore be likely a better tool for the job but the apparent field size of the visual image would still , not be directly transducible to the sensor. In order to capture the same real field on the sensor, you would have to adju...

Having a 30mm eyepiece will not change the sensor size. The only value of having more than 23.2mm in the photo tube is if the photo eyepiece is incapable of filling the sensor frame, a condition that I have never encountered. I'm not sure I understand what you're saying. With a 26.5mm photo tube th...

I've been reading up about microscope repair and one of the demons of the industry seems to be solidified grease. My mind came to a grease I'm familiar with from building keyboards (it is often used to grease switches in custom mechanical keyboards): Krytox. This stuff is not silicone grease, it's p...

Regarding high CRI COBs, here are some good ones:

https://www.digikey.com/products/en?keywords=SAWS1063a (10w)

https://www.digikey.com/products/en?keywords=SAWS1566a (25w)

The way to capture a wider real field to it, is to view a wider field in the photo tube. The way to do that is to use a photo eyepiece with a lower magnification. All of the NFK eyepieces including the 1.67x are 23mm pieces. Unless I'm misunderstanding, it should be impossible for them to capture 2...

apochronaut wrote: ↑

Tue Apr 21, 2020 10:27 pm

What is the magnification of your photo eyepiece?

Don't actually have one atm. BH-2 has 1.67x (rare - $750+,) 2.5x, 3.3x, 5x, 6.7x - http://www.alanwood.net/olympus/photo-eyepieces.html
I don't think even the 1.67x has a 26.5+ field number like the SWHK eyepieces

Eyepieces are made to do the job and usually no better. Otherwise, there is wasted production cost, the microscope has to be more expensive, losing ground to an economical competitor. Achromats are corrected for two wavelengths, apochromats, typically for 3. The human eye has only so much accuity a...

apochronaut wrote: ↑

Tue Apr 21, 2020 5:02 pm

...

The NFK photo eyepieces don't come in a super-wide flavor (as far as I am aware) and cover 20mm max. So, I think I have to either do direct projection (bad coz no eyepiece corrections) or focus a (small - smartphone sized, I suppose) sensor on one of the normal SWHK 26.5mm eyepieces.