Search found 4275 matches

by Hobbyst46
Sun Mar 10, 2024 6:46 am
Forum: Illumination Techniques
Topic: Epi Kölher illumination and infinity corrected systems
Replies: 7
Views: 464

Re: Epi Kölher illumination and infinity corrected systems

Also, I took a look at how my Olympus BH2-MA was made and it seems they added some diffuser inside of the illumination tube. Is this common practice? But why it is needed if they use some kind of Köhler illumination? In the old Zeiss Standard illumination collector, next to the light bulb, a mild d...
by Hobbyst46
Sat Mar 09, 2024 9:16 pm
Forum: Illumination Techniques
Topic: Epi Kölher illumination and infinity corrected systems
Replies: 7
Views: 464

Re: Epi Kölher illumination and infinity corrected systems

Thank you. But in the case of epi illumination, the objective is the condenser right? It is the same than an infinity condenser? That's why I was wondering if parallel beams were needed in this specific case. Wild guess: Kohler is needed in the epi- and infinity optics as well, since the illuminati...
by Hobbyst46
Fri Mar 08, 2024 3:56 pm
Forum: Illumination Techniques
Topic: Condenser Alignment.
Replies: 17
Views: 835

Re: Condenser Alignment.

Yes, as shown in the photo.
When the condenser and auxiliary lens are aligned, any blue fringe (if at all) will be symmetric, around the open iris.
by Hobbyst46
Thu Mar 07, 2024 8:04 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

I found one called a BM2000 ( looks a bit of a Nikon copy) on an Australian site they sell Nikon also. https://microscopes.com.au/collections/phase-contrast/products/bm2000-phase-contrast-microscope Looks ok but focus only on left side, Strange that a microscope costing that much does not include t...
by Hobbyst46
Wed Mar 06, 2024 11:11 pm
Forum: Illumination Techniques
Topic: Condenser Alignment.
Replies: 17
Views: 835

Re: Condenser Alignment.

Apo, a splendid contribution as well as thought provoking. Like Hobbyst46 I have Zeiss scopes fitted with the same AchApl 1.4 phase condensers. Never thought of centering lens of condenser proper. However below the condenser lies an auxiliary lens that does have centration control which I have neve...
by Hobbyst46
Wed Mar 06, 2024 10:33 pm
Forum: Illumination Techniques
Topic: Condenser Alignment.
Replies: 17
Views: 835

Re: Condenser Alignment.

centration - from the Merriam Webster Dictionary it appears to be a synonym of centering.
declipse - sounds to me a great and meaningful word, that is apparently missing in the same dictionary...
by Hobbyst46
Wed Mar 06, 2024 4:39 pm
Forum: Illumination Techniques
Topic: Condenser Alignment.
Replies: 17
Views: 835

Re: Condenser Alignment.

An excellent guide, Apo, thanks ! How would you suggest to test and align a turret achromat-aplanat 1.4 phase contrast condenser ? the basic lens gives an NA=0.32. It is fixed inside the body and I did not see any set screws around (though never seriously checked). The top lens, which makes it NA=1....
by Hobbyst46
Tue Mar 05, 2024 7:39 am
Forum: Digital processing
Topic: Chromatic aberrations filtering
Replies: 47
Views: 1451

Re: Chromatic aberrations filtering

In my experience, such unsymmetrical CA might originate from a misaligned condenser.
by Hobbyst46
Wed Feb 21, 2024 9:47 pm
Forum: Microscopy accessories
Topic: What tip size for micropipette
Replies: 7
Views: 621

Re: What tip size for micropipette

This old post (Oct 4, 2018) by "Question for Pipette users" by forum member 75RR, and response #23, might help.
by Hobbyst46
Sun Feb 11, 2024 4:39 pm
Forum: Camera systems and imaging
Topic: Recommendation Camera for Zeiss Axiovert 25CFL with 1x Adapter
Replies: 11
Views: 866

Re: Recommendation Camera for Zeiss Axiovert 25CFL with 1x Adapter

Some Olympus fluorescence-sensitive microscope cameras have a small sensor, 1/2.5" I think, and are meant to be used with a ~0.5X reducing lens for decent field coverage. The following might be somewhat relevant: https://www.microbehunter.com/microscopy-forum/viewtopic.php?f=9&t=18847&p=138958&hilit...
by Hobbyst46
Fri Feb 09, 2024 8:16 am
Forum: Microscopes and optics
Topic: Olympus SZ-FLR-200
Replies: 27
Views: 3762

Re: Olympus SZ-FLR-200

Do you really need 365nm wavelength ? if not, if 395nm or 420nm would be OK for the type of fluorescence you wish to see, I would opt for either the 395 or the 420 rather than the 365, for personal safety (eyesight !) reasons at least. And pay even less - ~130 USD as listed. I am not sure, but I ve...
by Hobbyst46
Thu Feb 08, 2024 7:18 pm
Forum: Microscopes and optics
Topic: Olympus SZ-FLR-200
Replies: 27
Views: 3762

Re: Olympus SZ-FLR-200

Reviving this thread again—I've been thinking about how I might observe fluorescence with my stereomicroscope, and I just learned that Amscope offers several versions of UV LED gooseneck lights, e.g.: https://amscope.com/products/led-6w-uv365?variant=40347665662127 , https://amscope.com/products/fb...
by Hobbyst46
Sun Feb 04, 2024 10:06 pm
Forum: Microscopes and optics
Topic: Stereoscope vs. Compound Microscope at Given Total Magnification
Replies: 6
Views: 587

Re: Stereoscope vs. Compound Microscope at Given Total Magnification

The field of view is the: field number/power of objective . Same calculation for stereo and compound. Also same total magnification calculation. The table above shows that the Spencer 9X eyepiece has a FN of 19.7 (probably 20?). For example, on my old Olympus stereo, the eyepiece FN is 22, so for a ...
by Hobbyst46
Sun Feb 04, 2024 8:32 pm
Forum: Microscopes and optics
Topic: Stereoscope vs. Compound Microscope at Given Total Magnification
Replies: 6
Views: 587

Re: Stereoscope vs. Compound Microscope at Given Total Magnification

Hello. This is a curiosity question, not trying to solve a specific problem. Could someone please describe the expected pros and cons — or direct folks to a website — of using a stereoscope (dissecting microscope) vs. a compound microscope at a given total magnification. For example, both equipped ...
by Hobbyst46
Fri Jan 26, 2024 1:12 pm
Forum: Microscopes and optics
Topic: NIKON PlanApo 100X/140 oil that is a PlanApo 60X/140 oil
Replies: 121
Views: 7826

Re: NIKON PlanApo 100X/140 oil that is a PlanApo 60X/140 oil

The only thing I can think of is to seal it with silicone along the edges between the metal and the glass, very carefully. Immersion oil penetrates many polymers, if left on them for many hours. Silicon sealing in general, is efficient against water, but less so against solvents and oils. Immersion...
by Hobbyst46
Tue Jan 23, 2024 8:40 pm
Forum: Microscopes and optics
Topic: NIKON PlanApo 100X/140 oil that is a PlanApo 60X/140 oil
Replies: 121
Views: 7826

Re: NIKON PlanApo 100X/140 oil that is a PlanApo 60X/140 oil

An interesting thread. Good luck !
BTW, I would not use ammonia to clean brass metal parts.
by Hobbyst46
Sat Jan 20, 2024 2:27 pm
Forum: Microscopes and optics
Topic: NIKON PlanApo 100X/140 oil that is a PlanApo 60X/140 oil
Replies: 121
Views: 7826

Re: NIKON PlanApo 100X/140 oil that is a PlanApo 60X/140 oil

I doubt that vacuum alone will eliminate trapped oil (if it is oil). Vacuum accelerates evaporation. Perhaps the abrupt decline of air pressure, when the vacuum pump was turned on, disintegrated a large oil drop to small droplets. Admittedly, small droplets will evaporate much faster than a large dr...
by Hobbyst46
Fri Jan 19, 2024 2:38 pm
Forum: Microscopes and optics
Topic: NIKON PlanApo 100X/140 oil that is a PlanApo 60X/140 oil
Replies: 121
Views: 7826

Re: NIKON PlanApo 100X/140 oil that is a PlanApo 60X/140 oil

stjepo wrote:
Fri Jan 19, 2024 2:28 pm
Any advice from you will help me.

Sorry and excuse my ignorance what is 'sa and ca'

Regards

Steve
Spherical aberrations and chromatic aberrations, respectively.
by Hobbyst46
Thu Jan 18, 2024 1:42 pm
Forum: Microscopes and optics
Topic: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?
Replies: 40
Views: 14324

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

Just thought I would dig up this old gem of a thread to convey the story of my success in restoring the opaque black paint on my Zeiss Ultra condenser. The product I used was a rattle can of VHT wheel paint . I didn't buy it specifically for this purpose - I shamelessly salvaged it, full, from a ro...
by Hobbyst46
Wed Jan 17, 2024 10:01 pm
Forum: Beginner's corner
Topic: SW380B no illumination getting through the condenser
Replies: 7
Views: 972

Re: SW380B no illumination getting through the condenser

Maybe there is no problem with the condenser - but the objective turret (nosepiece) is slightly off-position ?
by Hobbyst46
Mon Jan 15, 2024 8:21 am
Forum: Microscopes and optics
Topic: Help: does Koehler illumination requires a field lens in microscope?
Replies: 18
Views: 2209

Re: Help: does Koehler illumination requires a field lens in microscope?

In a complete Kohler setup, there is one more degree of freedom - the distance between the lamp and the collector optics. On my very old microscope for example, which dates from the 1950's, that distance can be adjusted by sliding the lamp housing slightly in or out, until the filament image is def...
by Hobbyst46
Sun Jan 14, 2024 8:17 pm
Forum: Microscopes and optics
Topic: Help: does Koehler illumination requires a field lens in microscope?
Replies: 18
Views: 2209

Re: Help: does Koehler illumination requires a field lens in microscope?

In a complete Kohler setup, there is one more degree of freedom - the distance between the lamp and the collector optics. On my very old microscope for example, which dates from the 1950's, that distance can be adjusted by sliding the lamp housing slightly in or out, until the filament image is defo...
by Hobbyst46
Thu Jan 11, 2024 3:20 pm
Forum: Beginner's corner
Topic: Looking for camera for Swift SW380B
Replies: 28
Views: 7603

Re: Looking for camera for Swift SW380B

Oh, to clarify: this is the typical information posted by sellers about their microscope cameras, which is where I could use some guidance picking out the 3-4 important details to compare among several different camera offerings. HAYEAR USB3.0 Digital Microscope Camera 8 Mega Pixels USB Live Video ...
by Hobbyst46
Wed Jan 10, 2024 9:59 am
Forum: Microscopes and optics
Topic: Correction Collar : Leitz [surprise]
Replies: 11
Views: 11545

Re: Correction Collar : Leitz [surprise]

The same footnote #2 applies to the two dry planapo objectives, 40X0.95 and 63X0.95, on the previous page of that same Leitz catalog (p. 19, top table).
by Hobbyst46
Sat Jan 06, 2024 4:58 pm
Forum: Camera systems and imaging
Topic: Camera sensor size to see bigger F.O.V.
Replies: 10
Views: 9453

Re: Camera sensor size to see bigger F.O.V.

What is the FN of the microscope ? a camera image width of 0.74mm from a 40X objective seems to me very large. If the FN for example is 26, the image diameter through the eyepieces would be 0.65mm. Or is the 0.74mm obtained from a 10X objective ?
by Hobbyst46
Thu Jan 04, 2024 10:25 pm
Forum: Microscopes and optics
Topic: No power to light sources on Leica DMRE
Replies: 9
Views: 8790

Re: No power to light sources on Leica DMRE

How about both bulbs are burnt out, normal end of life ?
by Hobbyst46
Wed Jan 03, 2024 7:20 pm
Forum: Home-made microscope adaptations
Topic: Dichromatic Illumination?
Replies: 61
Views: 103939

Re: Dichromatic Illumination?

Copied from the site of a firm named Synopsys. It shows the light losses when the tip is tapered to produce a narrower end.
They state that losses are substantial.
light guide.jpg
light guide.jpg (4.73 KiB) Viewed 19525 times
by Hobbyst46
Wed Jan 03, 2024 8:01 am
Forum: Home-made microscope adaptations
Topic: Dichromatic Illumination?
Replies: 61
Views: 103939

Re: Dichromatic Illumination?

A light guide does not "concentrate" light or "funnel" it or focus it, regardless of the geometry of the tip (square cut/frustum). As mentioned, one can axially drill a 5mm LED, insert a 1mm-diameter (say) optical fiber into the bore, attach it with epoxy, and cover the LED by means of a PVC shrink-...
by Hobbyst46
Tue Jan 02, 2024 9:33 pm
Forum: Home-made microscope adaptations
Topic: Dichromatic Illumination?
Replies: 61
Views: 103939

Re: Dichromatic Illumination?

… I think, still, that the OPs project will still offer some interesting results … Most definitely … I’m looking forward to seeing them MichaelG. Gee fellows, I don't know if there will be any interesting results. I am a complete beginner in microscopy and a lot of the stuff you guys talk about go ...