Search found 260 matches

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: 95

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: 129

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: 507

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: 13
Views: 572

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. ...
by wporter
Thu Nov 21, 2019 10:43 pm
Forum: Illumination Techniques
Topic: Identifying asbestos
Replies: 25
Views: 1434

Re: Identifying asbestos

Another possible reference, from the esteemed McCrone Research Institute:

http://www.mccroneinstitute.org/v/90/as ... tification
by wporter
Sat Nov 16, 2019 8:35 pm
Forum: Miscellaneous
Topic: Unlocking Nature's Secrets: The Serengeti Rules:
Replies: 5
Views: 326

Re: Unlocking Nature's Secrets: The Serengeti Rules:

It is currently on PBS in the US. It is an outstanding production.
by wporter
Wed Oct 23, 2019 8:18 pm
Forum: Microscopes and optics
Topic: XY-table for Zeiss standard inverted metallurgical
Replies: 2
Views: 472

Re: XY-table for Zeiss standard inverted metallurgical

Well, they were pretty practical for what the scopes were mainly used for: scanning metallic surfaces. The rails and grooves were usually juiced up with a suitable grease so that the friction and stiction were not a big issue. The Invertoscope was also made with an x-y stage for trans-illumination. ...
by wporter
Mon Sep 23, 2019 10:10 pm
Forum: Digital processing
Topic: Change lighting on laptop
Replies: 6
Views: 1759

Re: Change lighting on laptop

Fn-F6 to lower, Fn-F7 to brighten does not work? Sometimes there is a delay until the actual change...
by wporter
Thu Sep 12, 2019 6:06 pm
Forum: Microscopes and optics
Topic: B&L Balplan/Microzoom II light path selector
Replies: 9
Views: 1284

Re: B&L Balplan/Microzoom II light path selector

That is a mounting point for one end of a toggle spring, that provides the two positive setpoints for the prism position, i.e., in the light path or out of the light path. Yours is missing, which is OK, as the lever and prism will still work; they just aren't held in the in or out position very well...
by wporter
Thu Sep 12, 2019 1:39 am
Forum: Microscopes and optics
Topic: B&L Balplan/Microzoom II light path selector
Replies: 9
Views: 1284

Re: B&L Balplan/Microzoom II light path selector

No, just a prism moves with the lever.

Where exactly is this threaded boss?
by wporter
Mon Sep 09, 2019 3:25 pm
Forum: Identification help
Topic: Is this real?
Replies: 11
Views: 2562

Re: Is this real?

Floaters should be easy to distinguish from other FOV phenomenon. If you jerk your eye's point-of-focus to the side, the typical floater should lag a bit, i.e., not move as much as the jerk, but after a second or so, "catch up", and slide back to near the center of the field (at least the especially...
by wporter
Sat Sep 07, 2019 2:03 am
Forum: Beginner's corner
Topic: immersion oil question
Replies: 9
Views: 1051

Re: immersion oil question

I would think that the oil, especially if it eventually spreads out to form a sheen or layer, would probably negatively impact the air-water gaseous exchange rate or process.
by wporter
Sat Sep 07, 2019 1:45 am
Forum: For forum members who want to buy and sell equipment
Topic: Zeiss Universal for sale
Replies: 8
Views: 1370

Re: Zeiss Universal for sale

The protrusion is a 3-layer slide holding multiple filters.
by wporter
Wed Jun 26, 2019 3:45 pm
Forum: Microscopes and optics
Topic: Microscope storage temperature
Replies: 15
Views: 1670

Re: Microscope storage temperature

I don't think a differential thermal expansion is a problem, unless you put the microscope in an oven or other source of high heat. The bigger problem for scopes is high humidity, causing fungal growth on the glass surfaces. Some people in tropical climes use enclosures with dehumidification in whic...
by wporter
Sat Jun 22, 2019 2:00 pm
Forum: Microscopes and optics
Topic: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?
Replies: 35
Views: 3958

Re: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?

So, I will try black paint, perhaps it will help some. Carefully of course. Need to verify that the paint is compatible with immersion oil. Good point; I now retract my suggestion to use hobby paint, unless it claims to be oil-resistant. Radio-controlled airplane paint might work, if for use on pla...
by wporter
Sat Jun 22, 2019 12:25 am
Forum: Microscopes and optics
Topic: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?
Replies: 35
Views: 3958

Re: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?

I'm not sure if it makes a lot of difference what paint you use, but you might go to a hobby shop and get a small jar of flat black paint that modelers use on model planes and trains. Clean the surface with acetone, and stroke gently with a modeler's paintbrush upwards along the outside of the frust...
by wporter
Mon Jun 17, 2019 5:20 pm
Forum: Camera systems and imaging
Topic: Using flash produces blurred images
Replies: 24
Views: 3029

Re: Using flash produces blurred images

Exactly; if the flash is off-center and the lighting is thus not optimal, than the camera auto-exposure may be using too long of an exposure, picking up vibration.
by wporter
Mon Jun 17, 2019 2:14 pm
Forum: Camera systems and imaging
Topic: Using flash produces blurred images
Replies: 24
Views: 3029

Re: Using flash produces blurred images

The faint bands above all the edges might be caused by movement during exposure. Other than that, try putting a diffuser into the flash light-path. Another thing to try is substituting a hand-held led flashlight for the flash unit, and move it around laterally at the flash's normal position, to see ...
by wporter
Thu Jun 06, 2019 1:47 pm
Forum: Beginner's corner
Topic: What is the difference between these microscopes ? Which one is better ?
Replies: 38
Views: 6344

Re: What is the difference between these microscopes ? Which one is better ?

It seems to me that no one asking questions on a microscope forum should be frightened by a little 'technobabble'. It's like someone asking the question on a forum for four-wheel-drive vehicles: which is better, a Jeep Model x or a Land Rover model y. You are going to get a lot of technobabble, and ...
by wporter
Fri May 31, 2019 3:49 pm
Forum: Beginner's corner
Topic: What Do These Different Stains Do?
Replies: 7
Views: 1512

Re: What Do These Different Stains Do?

Thanks for the links to Conn's, very useful.
by wporter
Fri May 31, 2019 1:01 pm
Forum: Beginner's corner
Topic: What Do These Different Stains Do?
Replies: 7
Views: 1512

Re: What Do These Different Stains Do?

Here is some more on various protocols, for those wanting information overload:

http://www.ihcworld.com/protocol_database.htm
by wporter
Thu May 16, 2019 9:45 pm
Forum: My microscope
Topic: IOR ML-4M
Replies: 21
Views: 6404

Re: IOR ML-4M

The projection screen is possibly for this IOR microscope, the MC7, which has the broad top surface that matches the screen shape and size:
by wporter
Thu May 09, 2019 7:34 pm
Forum: Microscopy accessories
Topic: AO 820 Microtome Retract Question
Replies: 2
Views: 1005

Re: AO 820 Microtome Retract Question

No, the 820 moves the specimen strictly in an up-and-down motion, no extra motions for clearing the blade, etc. It jogs the specimen forwards only toward the blade, at the top point of the stroke. So the motion is straight down for the cut, straight up without any forward-or-backward motion, jog for...
by wporter
Thu May 09, 2019 7:00 pm
Forum: Microscopes and optics
Topic: Balplan 10x objectives
Replies: 3
Views: 881

Re: Balplan 10x objectives

Well, Harold must have fallen off the boat. I'm not sure I would want to fall into the Yangtze, these days. Thanks for the breakdown. Comprehensive as usual. All of the objectives pictured are parfocal. The working distances are about 1mm for the left two, 10mm for the shorty, and 2mm for the newest...
by wporter
Wed May 08, 2019 11:45 pm
Forum: Microscopes and optics
Topic: Balplan 10x objectives
Replies: 3
Views: 881

Balplan 10x objectives

Here are five different 10x objectives that look to be for the Balplan, the farthest left a flat-field that looks very much like the adjacent planachromat. Does someone know the difference and/or the evolution of the 10x objectives as displayed by these? I have some guesses, but it would be nice to ...
by wporter
Wed May 08, 2019 9:50 pm
Forum: Microscopes and optics
Topic: Advice for microscope for microphotography
Replies: 7
Views: 2111

Re: Advice for microscope for microphotography

Those are nice images! If I were you, my next step would not be an upgrade of scope or camera, but rather a move to focus-stacking. That would significantly enhance the appeal of your images, which seem to be fine in terms of resolution, focus, etc. (which, if deficient, would have been the reason f...
by wporter
Wed May 08, 2019 5:42 pm
Forum: My microscope
Topic: Chinese microscope manufacturers overview
Replies: 72
Views: 21709

Re: Chinese microscope manufacturers overview

This thread has gone way off course; but to get it back on track, and to satisfy both antagonistic parties (older used big-four vs new Chinese), here's my suggestion: satisfied users of a good-to-excellent Chinese microscope should write a review, or at least a short note, about how great it is. We ...
by wporter
Thu May 02, 2019 2:33 pm
Forum: Camera systems and imaging
Topic: A question about the Past - shutter induced-vibrations in film cameras
Replies: 4
Views: 1318

Re: A question about the Past - shutter induced-vibrations in film cameras

I think we're spoiled! We expect to fasten our fancy new DSLR up to the scope and get instant gratification, just like taking an image of a field of flowers. Plus, 1) the old in-the-lens leaf shutters had very little vibration, compared to modern SLRs with mirror-slap and focal-plane shutters; 2) no...