Search found 2389 matches

by MicroBob
Fri Jan 22, 2021 6:59 am
Forum: Miscellaneous
Topic: Vibration dampening
Replies: 6
Views: 100

Re: Vibration dampening

After a few calm years he will become very strong! When I look into my office/lab the biggest problem would be chemicals, hot plates, special electric stuff and microtome and other very sharp knives. From 3 on it wouldn't take long any more to make a child understand that the room is off limits, but...
by MicroBob
Fri Jan 22, 2021 6:28 am
Forum: Microscopes and optics
Topic: objective comparison
Replies: 3
Views: 70

Re: objective comparison

Hi together, I think the Leitz standards of "planar" have changed over the years so the genereation of objective has to be taken into account. The first planar objective series from about 1960 consisted of fairly plain looking objectives with highly reflective chrome. This was pre-Orthoplan, so no n...
by MicroBob
Thu Jan 21, 2021 9:01 pm
Forum: Specimens, samples and slides
Topic: Staining lichen
Replies: 3
Views: 37

Re: Staining lichen

Hi Mike, on our website you can find Schömmers "Kryptogamenpraktikum": http://www.mikrohamburg.de/Schoemmer/Schoemmer.pdf The name of the book is difficult to decipher even for me as a german, but the book itself is an insider tip. When you look for "Flechten" = lichen, you will find the right chapt...
by MicroBob
Thu Jan 21, 2021 4:31 pm
Forum: Microscopes and optics
Topic: What even is this: Plan Apo 40x/1.0 W infinity f=180 unbranded m25 75mm long
Replies: 9
Views: 146

Re: What even is this: Plan Apo 40x/1.0 W infinity f=180 unbranded m25 75mm long

Hi Doron, I thought of a thermocouple as they are small. The more common PT or NTC sensors would be too big to fit next to the front lens. I don't know the electrical resistance of thermocouples, but a resistance measurement might help to narrow down the selection of opportunities. These could also ...
by MicroBob
Thu Jan 21, 2021 4:27 pm
Forum: Pictures and Videos
Topic: Desmid: Closterium littorale
Replies: 5
Views: 80

Re: Desmid: Closterium littorale

Hi Carlos,
nice video!
What I find fascinating are these revolving gypsum crystals in the tips.

Bob
by MicroBob
Thu Jan 21, 2021 4:16 pm
Forum: Illumination Techniques
Topic: scan lines in my camera image
Replies: 3
Views: 53

Re: scan lines in my camera image

Hi Don, your incandescent lamp should be powered with current that is rectified and smoothed by a condensator - with proper DC power it doesn't flicker. LEDs can go on and off in an instant an can flicker severely if not powered by smoothed DC. Sometimes LED lamps are powered just with rectified AC ...
by MicroBob
Thu Jan 21, 2021 4:04 pm
Forum: Miscellaneous
Topic: Vibration dampening
Replies: 6
Views: 100

Re: Vibration dampening

Hi, I would suggest a three step solution: - fat steel plate under the microscope (4x the denstity of concrete) e.g. 400x400x40mm = 50kg - foam rubber under the steel plate, amount chosen so the rubber already starts to be compressed, perhaps 50mm thick uncompressed - velcro loop carpet and a velcro...
by MicroBob
Thu Jan 21, 2021 7:26 am
Forum: Microscopes and optics
Topic: What even is this: Plan Apo 40x/1.0 W infinity f=180 unbranded m25 75mm long
Replies: 9
Views: 146

Re: What even is this: Plan Apo 40x/1.0 W infinity f=180 unbranded m25 75mm long

Interesting catch!
With all the heating it would make sense to measure the temperature. Is it possible that the tiny elements next to the front lens are a thermocouple? They put out a tiny voltage, perhaps you can measure it.

Bob
by MicroBob
Wed Jan 20, 2021 9:53 pm
Forum: Camera systems and imaging
Topic: Chinese Unbranded 48mp C-mount Industrial HDMI Camera
Replies: 11
Views: 147

Re: Chineses Unbranded 48mp C-mount Industrial HDMI Camera

Hi John, apparently the chinese printed all necessary information on the outside of the housing, perhaps there is a side with closer instructions? What I can see from the print on the housing is that it is powered by a V8 motor and at 4800W it consumes quite some energy, not for a V8 but for a camer...
by MicroBob
Tue Jan 19, 2021 3:23 pm
Forum: Beginner's corner
Topic: Inverted inquiry
Replies: 7
Views: 184

Re: Inverted inquiry

I just have a basic Olympus Ck with max 20:1 objective and only coarse focus and bicycle lamp. It can be used through the bottom of a slide or petri dish. There are higher power objectives that work through the bottom of petri dishes, like the 32:1 Leitz, but the higher the power the rarer these obj...
by MicroBob
Mon Jan 18, 2021 9:19 pm
Forum: Specimens, samples and slides
Topic: Desmids after 7 months in an Eppendorf tube
Replies: 2
Views: 123

Re: Desmids after 7 months in an Eppendorf tube

Hi Glen, yes, like the right one, 2ml. The lid closes water proof and clicks in. I got the tube by post in an ordinary paper envelope. Apparently there is a recycling process running with very little waste. Some desmids reproduce very slowly so some of these might actually be from the first generati...
by MicroBob
Mon Jan 18, 2021 7:03 am
Forum: Beginner's corner
Topic: Need help figuring out which compound microscope I should buy.
Replies: 5
Views: 120

Re: Need help figuring out which compound microscope I should buy.

Hi Mondo, microscope choice is discussed in this forum frequently and many people look for the same thing as you, a usable microscope to start with, not too limiting, not too expensive. So you might have a look what has been recommdended in the past. Camera choice is very much a question of expected...
by MicroBob
Sun Jan 17, 2021 8:13 pm
Forum: Beginner's corner
Topic: PH alignment without a CT
Replies: 21
Views: 374

Re: PH alignment without a CT

The way the condenser is made I wouldn't expect any fancy type of screw head: Smaller phillips or allen screw driver would be what I would try first.
by MicroBob
Sun Jan 17, 2021 8:08 pm
Forum: Microscopes and optics
Topic: How to check out Zeiss darkfield 1.2-1.4 NA "ultracondenser" without a Zeiss microscope?
Replies: 24
Views: 409

Re: How to check out Zeiss darkfield 1.2-1.4 NA "ultracondenser" without a Zeiss microscope?

No, my condenser doesn't have this stop. It seems to have a glass plate on the bottom, held by a screwed i ring. To me the catalog image seems to be an illustration that is 20-30 years older than the catalog itself. These Ultra condensers are not that frequent on the market and for sure nothing they...
by MicroBob
Sun Jan 17, 2021 11:47 am
Forum: Microscopes and optics
Topic: How to check out Zeiss darkfield 1.2-1.4 NA "ultracondenser" without a Zeiss microscope?
Replies: 24
Views: 409

Re: How to check out Zeiss darkfield 1.2-1.4 NA "ultracondenser" without a Zeiss microscope?

Hi Hans, ok, then this is the condenser I had in mind. I have checked my one and found no delaminations or whatever you see there. In a darkfield setup dirt in the mountant or on slide or cover slip show up very intensively. This might mean that damages inside a dark field condenser are also very ob...
by MicroBob
Sun Jan 17, 2021 8:52 am
Forum: My microscope
Topic: Chinese Wild M3 Clone: It's pretty good! [With comparison to mz6]
Replies: 35
Views: 9157

Re: Chinese Wild M3 Clone: It's pretty good! [With comparison to mz6]

In case someone wants to bid on this ebay-offer: Have a look at the picture of the corroded front lens. Whatever has cause this was close to the whole microscope and I would suspect that there is more damage.
by MicroBob
Sun Jan 17, 2021 12:53 am
Forum: Microscopes and optics
Topic: How to check out Zeiss darkfield 1.2-1.4 NA "ultracondenser" without a Zeiss microscope?
Replies: 24
Views: 409

Re: How to check out Zeiss darkfield 1.2-1.4 NA "ultracondenser" without a Zeiss microscope?

Hi Hans, perhaps we should have a closer look at what condenser you have there precisely. It doesn't have the ring dovetail for the Zeiss West Standard series. It is not the type for the Zeiss Jena models like the LG. There seems to be a cylindrical mounting surface, but fairly unscratched for a wel...
by MicroBob
Sat Jan 16, 2021 8:26 pm
Forum: Specimens, samples and slides
Topic: Desmids after 7 months in an Eppendorf tube
Replies: 2
Views: 123

Desmids after 7 months in an Eppendorf tube

Hi together, today I had a look at the window sill of my office/lab bay window: I still keep a water sample rich in desmids in a 2 ml Eppendorf tube there, next to some other water samples and two plancton aquariums. Since it has been standing there closed for 7 months I thought I should give it a s...
by MicroBob
Sat Jan 16, 2021 8:16 pm
Forum: Microscopes and optics
Topic: Silicone immersion objectives - any experience?
Replies: 29
Views: 465

Re: Silicone immersion objectives - any experience?

Hi Viktor,
please report how you get on with this very special objective. A 40:1 1.0 will be useful for many purposes. Do you know the free working distance to the cover slip?
Now it would be nice if you can find a 100:1 silicone immersion to accompany it! :lol:

Bob
by MicroBob
Sat Jan 16, 2021 11:20 am
Forum: Beginner's corner
Topic: PH alignment without a CT
Replies: 21
Views: 374

Re: PH alignment without a CT

They are also very useful to check: - whether the back lens of the objective is clean - whether it is fully illuminated by the condenser aperture - whether there are delaminations or other defects in the lens stack of the objective Some microscopes have a Bertrand lens built in, sometimes it can be ...
by MicroBob
Sat Jan 16, 2021 9:40 am
Forum: Beginner's corner
Topic: PH alignment without a CT
Replies: 21
Views: 374

Re: PH alignment without a CT

What is a CT?
by MicroBob
Sat Jan 16, 2021 7:51 am
Forum: Microscopes and optics
Topic: Need help deciding between Motic BA310E & Panthera CC
Replies: 9
Views: 227

Re: Need help deciding between Motic BA310E & Panthera CC

Here is the contrast technique described that he uses - obviously worth a try! His images have more a 3-dimensional look than the optical sectioning effect of DIC. For plancton life his setup may very well be better auited than DIC, why not? Here the LabCam adapter types can be seen, move mouse on l...
by MicroBob
Sat Jan 16, 2021 7:32 am
Forum: Microscopes and optics
Topic: How to check out Zeiss darkfield 1.2-1.4 NA "ultracondenser" without a Zeiss microscope?
Replies: 24
Views: 409

Re: How to check out Zeiss darkfield 1.2-1.4 NA "ultracondenser" without a Zeiss microscope?

Hi Hans, when you put a piece of paper onto the top lens and point the bottom of the condenser towards a light source the paper should be illuminated. I think it is a good sign that no light passes through in your test as the condenser has to block it. Typical damages are paint flaking of and scratc...
by MicroBob
Fri Jan 15, 2021 4:04 pm
Forum: Microscopes and optics
Topic: Need help deciding between Motic BA310E & Panthera CC
Replies: 9
Views: 227

Re: Need help deciding between Motic BA310E & Panthera CC

The difference between the trino heads might actually be important. When you chase plancton life it is important to have an image splitter, which both have. For photography it is good to use a lot of light for low ISO settings and short exposures and the light in the eyepieces should not blind you. ...
by MicroBob
Fri Jan 15, 2021 12:41 pm
Forum: Microscopes and optics
Topic: Silicone immersion objectives - any experience?
Replies: 29
Views: 465

Re: Silicone immersion objectives - any experience?

Oil can be removed fairly well by wiping with lighter fluid, so objective and slides are really clean. Silicone is quite inert and doesn't dissolve in usual cleaning fluids, so you push it from left to right and back to the left. A fine silicone layer or tiny drops of silicone oil repell water and o...
by MicroBob
Fri Jan 15, 2021 11:20 am
Forum: Microscopes and optics
Topic: Silicone immersion objectives - any experience?
Replies: 29
Views: 465

Re: Silicone immersion objectives - any experience?

Hi Vikor, from the r.i. that sounds quite interesting for work on preparations with a thicker water layer. But silicone really is messy. It invisibly spreads over surrounding surfaces and interferes with wettability and adhesion. Car painters do hate it! For workshop use thin silicone oil in spray c...
by MicroBob
Thu Jan 14, 2021 8:21 pm
Forum: Home-made microscope adaptations
Topic: Slit Interference Contrast
Replies: 4
Views: 124

Re: Slit Interference Contrast

Hi,
that looks very promising!
Is your setup similar to the PZO DIC with slit condenser? PZO uses a stit aperture in the condenser and an analyser in an intermediate tube between microscope head and observation tube.
Did you see a dependency on the orientation of the diatoms?

Bob
by MicroBob
Thu Jan 14, 2021 6:05 pm
Forum: Beginner's corner
Topic: Reichert received and a question
Replies: 31
Views: 485

Re: Reichert received and a question

I just bought a pack of 10 sealed 693ZZ bearings from China for 3.17 + free shipping. Ridiculous, really. Hi Phil, I would suggest that you check the size and put a file to it to check whether they are actually hardened. I had two occasions where dimensions of chinese ball bearings were completely ...
by MicroBob
Thu Jan 14, 2021 5:34 pm
Forum: Beginner's corner
Topic: Oculars or auxiliary lens
Replies: 7
Views: 199

Re: Oculars or auxiliary lens

Hi Scarodactyl,
you must be right. I googled and Leica says their M205 has the highest n.a. of all at 0,35:

https://www.leica-microsystems.com/de/p ... -m205-fca/

What n.a. had the most powerful stereo microscope you used and how useful did you find this?

Bob
by MicroBob
Thu Jan 14, 2021 7:33 am
Forum: Beginner's corner
Topic: Oculars or auxiliary lens
Replies: 7
Views: 199

Re: Oculars or auxiliary lens

Hi together, for my 1970s Leitz Großfeld Stereocmicroscope TS I have these numeric apertures: 1,0x 0,05 1,6x 0,62 2,5x 0,8 4,0x 0,8 10x 1,0 The 1x gives an exceptionally crisp image, the 4x quite a good one, the 10x perfectly usable but not overwhelming. I don't own the others. Since the camera can ...