Search found 285 matches

by wporter
Sun Mar 22, 2020 12:06 am
Forum: Camera systems and imaging
Topic: Olympus BHS vs modern microscope
Replies: 8
Views: 339

Re: Olympus BHS vs modern microscope

Most comparisons, very much such as the one you linked to, are specious, and are generally poorly done. It is most always an apples-to-oranges comparison: the N.A.s are not the same; the focus is on different points of the specimen for the different lenses; the magnifications are not the same; the p...
by wporter
Fri Feb 28, 2020 4:46 pm
Forum: Microscopes and optics
Topic: Leica Reichert Jung Polyvar (models)
Replies: 46
Views: 11051

Re: Leica Reichert Jung Polyvar (models)

Member wporter is in the midst of a move and does not have access to documentation, nor his Reichert objectives, so he's not much help. My scope is a Univar, but uses some of the same optics as the Polyvar Met. But I will say that the Plan Fluors go down at least to 5x, although quite frankly, at th...
by wporter
Mon Feb 10, 2020 5:54 pm
Forum: Beginner's corner
Topic: DNA?
Replies: 7
Views: 2564

Re: DNA?

DNA is visible with a 100x objective, but it is all coiled up (with the coils coiled, etc.) into a chromosome. So you will not be able to see the actual double-helix of DNA, just the giant hyper-organized wad that is the chromosome: a reduction in length from the meter(s)-long DNA strand into a chro...
by wporter
Mon Feb 10, 2020 5:35 pm
Forum: Microscopes and optics
Topic: B&L (or Cambridge) PhotoZoom inverted microscope?
Replies: 5
Views: 3272

Re: B&L (or Cambridge) PhotoZoom inverted microscope?

The ornamental design is downloadable from here (USD308879, 1990): http://www.freepatentsonline.com/D308879.html The rubber objective turret cover patent (!) along with a lot more (!?), is detailed here (US 4,770,520, 1988): http://www.freepatentsonline.com/4770520.html Why the patent 4,770,520 has ...
by wporter
Mon Feb 10, 2020 12:08 am
Forum: Microscopes and optics
Topic: 23.2 vs 30mm
Replies: 38
Views: 5715

Re: 23.2 vs 30mm

"I have usually heard it described as the FoV you'd get at 1x..." Yes, that's right; thanks, Scarodactyl. It is still a cumbersome number. So you have a real FOV with a 60x objective, e.g., that in microns will be (FOVmm*1000)/60). Fine; you want to measure a critter's length for a scale bar on the ...
by wporter
Sun Feb 09, 2020 5:39 pm
Forum: Microscopes and optics
Topic: 23.2 vs 30mm
Replies: 38
Views: 5715

Re: 23.2 vs 30mm

Well said, Phil. Nice summary. I, too, would prefer standardization on apparent field. FOV in mm seems somehow extracted from some sort of optical design calculations, with not much users can relate to. It would be nice to have an easy way to determine apparent field of an eyepiece (relative field s...
by wporter
Thu Jan 30, 2020 2:16 am
Forum: Microscopes and optics
Topic: Leica Reichert Jung Polyvar (models)
Replies: 46
Views: 11051

Re: Leica Reichert Jung Polyvar (models)

"I'm wondering if it would be possible to put together a best guess on the attributes of various AO/Reichert/Leica infinity optics?" What a great idea. Maybe also separate columns for thread size (e.g., M28 for some of the Reichert Austria ones for the Univar/Polyvars), and for the needed type of ey...
by wporter
Thu Jan 30, 2020 2:08 am
Forum: My microscope
Topic: Reichert Polyvar Microscope
Replies: 60
Views: 8251

Re: Reichert Polyvar Microscope

It's a one-part, UV-hardening liquid. Relative to epoxies or other messy or problematic adhesives like super glues, very nice stuff to work with. For those who are using it to repair joined prism assemblies, stacked lenses, or other complex arrangements, some kind of jig or other hold-it-all-in-plac...
by wporter
Wed Jan 29, 2020 8:11 pm
Forum: My microscope
Topic: Reichert Polyvar Microscope
Replies: 60
Views: 8251

Re: Reichert Polyvar Microscope

"Do you have to put the resin in a vacuum to remove possible bubbles?" No, definitely not. Although this depends on not having any entrained bubbles to begin with. Bubbles will arise from shaking the Norland bottle before using, or from applying in a manner that adds bubbles as you apply a drop to o...
by wporter
Wed Jan 29, 2020 5:42 pm
Forum: My microscope
Topic: Reichert Polyvar Microscope
Replies: 60
Views: 8251

Re: Reichert Polyvar Microscope

For curing Norland 61, I use a UV flashlight for the initial set, at a few different angles for 20 min-1 hour total exposure. I then lay it out in the sun for a couple of days, usually placing the lens or prism on top of a mirror or white cardboard. Never had any failures, knock on wood.
by wporter
Sun Jan 26, 2020 7:57 pm
Forum: Beginner's corner
Topic: What affects the image produced from two different microscopes?
Replies: 5
Views: 1263

Re: What affects the image produced from two different microscopes?

You've sorta answered your own question.... Not to harsh on the inquiry, because it's a good one, and the images are good, too, but you must decrease the number of variables. That is, image the same subject, at the same magnification, polarizer angle, lighting (as much as possible), etc. You cannot ...
by wporter
Thu Jan 23, 2020 12:42 am
Forum: My microscope
Topic: Help on Leitz lens...can you help me with the shopping list ?
Replies: 8
Views: 2590

Re: Help on Leitz lens...can you help me with the shopping list ?

The EFs are the lowest grade of objective, I believe achromats. You might want to purchase only the NPL (near-plan?) or the better PL (wider zone of planarity than NPL).
by wporter
Wed Jan 15, 2020 5:07 pm
Forum: Beginner's corner
Topic: Advice on next upgrade to a T390, looking to observe yeast and bacteria.
Replies: 10
Views: 1447

Re: Advice on next upgrade to a T390, looking to observe yeast and bacteria.

Really well-done exposition and images, Phil. Very nice comparisons.

I wish we had more of this kind of answer on this forum; good images of this or that to support a point are generally worth much more than mere verbal descriptions.
by wporter
Fri Jan 03, 2020 1:23 am
Forum: Pictures and Videos
Topic: Salt mix
Replies: 18
Views: 1997

Re: Salt mix

Very dramatic, and nicely focused.
by wporter
Tue Dec 24, 2019 11:44 pm
Forum: For forum members who want to buy and sell equipment
Topic: Olympus BH2 BHS UMA Nomarski DIC Metallurgical Microscope
Replies: 6
Views: 1285

Re: Olympus BH2 BHS UMA Nomarski DIC Metallurgical Microscope

You might get a manual for this Zeiss and become familiar with the DIC components that are necessary, and then talk to the seller to make sure all of the components come with the scope. Oftimes sellers claim DIC, but half or all of the needed parts are defective or missing. It is highly desirable th...
by wporter
Mon Dec 23, 2019 6:26 pm
Forum: Beginner's corner
Topic: Does a DSLR adapter need a lens in it?
Replies: 38
Views: 2499

Re: Does a DSLR adapter need a lens in it?

Viewing eyepieces will also project a real image, and are not that different from projection eyepieces in that regard. This is easily confirmed by holding a ground glass screen or frosted slide above your normal (viewing) eyepiece; you will get a real image projected upon the screen. The real and vi...
by wporter
Fri Dec 20, 2019 12:39 am
Forum: Illumination Techniques
Topic: dIY DIC
Replies: 33
Views: 8115

Re: dIY DIC

The objectives marked 'DIC' don't have internal prisms, but rather have high-quality strain-free & occlusion-free optical glass. There is still a need for a prism external to and above the objective, and one below the objective. See the below page for a nice color graphic (Fig. 1) of a DIC optical s...
by wporter
Wed Dec 18, 2019 11:18 pm
Forum: Microscopes and optics
Topic: Urgent! Labovert Leitz - please advise!
Replies: 12
Views: 1304

Re: Urgent! Labovert Leitz - please advise!

I don't need any of these parts at the moment; too much duplication of what I have already. Thanks for the heads-up, though.

Anyone else? Even though it's on Facebook Marketplace (which I guess is like Craigslist), the seller may package it up and ship it for a small sum.
by wporter
Wed Dec 18, 2019 2:59 am
Forum: Microscopes and optics
Topic: Urgent! Labovert Leitz - please advise!
Replies: 12
Views: 1304

Re: Urgent! Labovert Leitz - please advise!

It might work; it has to fit properly. The Leitz stage for this scope looks just like an upright scope x-y stage, and in fact may be one.
by wporter
Tue Dec 17, 2019 10:01 pm
Forum: Specimens, samples and slides
Topic: Help to identify anomaly in blood.
Replies: 7
Views: 1830

Re: Help to identify anomaly in blood.

I'm sorry, but we're not allowed to give medical diagnoses on this forum.

But it was nice knowing you, MicroBob.
by wporter
Tue Dec 17, 2019 7:27 pm
Forum: Specimens, samples and slides
Topic: Help to identify anomaly in blood.
Replies: 7
Views: 1830

Re: Help to identify anomaly in blood.

Possibly an air bubble.
by wporter
Mon Dec 16, 2019 10:29 pm
Forum: Microscopes and optics
Topic: Urgent! Labovert Leitz - please advise!
Replies: 12
Views: 1304

Re: Urgent! Labovert Leitz - please advise!

Laboverts are very nice scopes. They even have their own patent: US patent 4,619,503, which also covers the Fluovert (the fluorescence version). The idea was to make an inverted stand more like the usual upright scope, which would lessen confusion when moving back-and-forth between the two types. Th...
by wporter
Sat Dec 14, 2019 8:39 pm
Forum: Miscellaneous
Topic: Protist behavioral complexity
Replies: 8
Views: 2236

Re: Protist behavioral complexity

Why on earth would a biologist think that single cells were "genetically programmed to respond uniformly to some stimulus"? Cells are well known to have a multitude of different receptors in their cell membranes. Depending on the effect of a variable stimulus on different types and/or different numb...
by wporter
Sat Dec 14, 2019 3:28 pm
Forum: Beginner's corner
Topic: Microscope -Avian Disease's
Replies: 9
Views: 938

Re: Microscope -Avian Disease's

I'm sure Apo will chime in, but from my perspective, 1) it looks like a nice scope, 2) you don't need DIC, probably limited application for bacteria, and may not be available for this scope and certainly not for your budget; 3) the scope is shown with B&L eyepieces; get yourself some AO eyepieces. A...
by wporter
Sat Dec 07, 2019 6:08 pm
Forum: Microscopes and optics
Topic: Neural lens paper
Replies: 1
Views: 384

Neural lens paper

by wporter
Thu Dec 05, 2019 7:23 pm
Forum: Microscopes and optics
Topic: Meaning of Red dot on a Leitz eyepiece?
Replies: 2
Views: 400

Re: Meaning of Red dot on a Leitz eyepiece?

High eyepoint eyepieces are generally meant for people who wear eyeglasses, so they don't bump their glasses into the eyelens of the eyepiece. The red dot seems to indicate a Leitz eyepiece that is best for photography; perhaps this means that it is a projective eyepiece (not for afocal), but there ...
by wporter
Thu Dec 05, 2019 12:35 am
Forum: Miscellaneous
Topic: Is there a recognised definition of ‘Microplastics’ ?
Replies: 5
Views: 1412

Re: Is there a recognised definition of ‘Microplastics’ ?

"How can quantitative surveys of ‘Microplastics’ have any credibility ?" Why not? When you read a simplistic summary of research in the popular press, sometimes it makes no sense. You will have to read the journal article to understand the constraints and methodologies involved, and to understand th...
by wporter
Tue Nov 26, 2019 5:14 pm
Forum: Microscopes and optics
Topic: Ortholux tube lens
Replies: 5
Views: 1103

Re: Ortholux tube lens

Thanks for the very comprehensive info, Dave P. I know many the later (1980s) 160mm TL Leitz scopes used FSA heads also, although they often had a dash with some additional letters, indicating particular models with different features. Is that when the the 42mm head mount came in? ( versus the earli...
by wporter
Sat Nov 23, 2019 3:13 pm
Forum: Beginner's corner
Topic: thinking out loud here - moral thoughts
Replies: 21
Views: 2631

Re: thinking out loud here - moral thoughts

If it makes you feel better, by all means return them to their original habitat. But realize that this action is for you, not them. In some manner this can be seen as symbolically honoring or respecting life, but it is probably only really meaningful to you, not so much to the microscopic critters. ...