Search found 2193 matches

by MicroBob
Tue Jul 07, 2020 6:52 pm
Forum: Microscopes and optics
Topic: Please help a microscope noob with objectives
Replies: 14
Views: 470

Re: Please help a microscope noob with objectives

Hi Aaron, I think the combination of computer and optics has lots of future. Especially in the form of an open source project where many people contribute to the further development. Most 160mm objectives are calculated with a residual chromatic error that is corrected by the eyepiece. So if your ca...
by MicroBob
Tue Jul 07, 2020 1:06 pm
Forum: Beginner's corner
Topic: 'Noise' when viewing at higher magnifications
Replies: 12
Views: 664

Re: 'Noise' when viewing at higher magnifications

Hi Luca, by moving or turning individual components you can single out the source of the obstractions. It is true that imperfections and dust show up more when observing with higher powered objectives. These also show faults in eyepieces or in camera objectives. The obstractions might be mouche vola...
by MicroBob
Mon Jul 06, 2020 5:04 pm
Forum: Home-made microscope adaptations
Topic: 3D printing - AMScope / Canon adaptor, for Barlow telescope lens. (And many others)
Replies: 5
Views: 1637

Re: 3D printing - AMScope / Canon adaptor, for Barlow telescope lens. (And many others)

Hi Sarah, to clean you front lens you can use surgical spirits or lighter fuel. Generally the image content of high magnification microscope images is low, just a couple of megapixels. It is very important to avoid mirror and shutter shock as they blur the images. Some cameras allow shock free relea...
by MicroBob
Sun Jul 05, 2020 4:07 pm
Forum: Pictures and Videos
Topic: Horsefly portrait
Replies: 5
Views: 299

Re: Horsefly portrait

Hi together, here one more photo, this time from the side. I wasn't able to do a closer identification so far, it is not the ordinary variant. The TG4 has a bayonett in front of the objective which is normaly covered with a ring. There is a 3D model that fits this bayonett on Thingiverse, but the pr...
by MicroBob
Sat Jul 04, 2020 7:13 pm
Forum: Pictures and Videos
Topic: Horsefly portrait
Replies: 5
Views: 299

Horsefly portrait

Ho together, here a potrait of a horsefly, taken with an Olympus TG-4 outdoor camera in "microscope mode" at f=14. The photo shows how much is possible even with limited equipment. This is a rugged compact camera I use while paddling. Image quality on these cameras is always limited, probably becaus...
by MicroBob
Thu Jul 02, 2020 8:02 pm
Forum: Specimens, samples and slides
Topic: Diatom selection experience
Replies: 38
Views: 2939

Re: A tip and a question about a slide of clean diatoms without silt

I think the importance of arranged slides has recedet: One can assemble the arrangement from individual photos and gets a result that can be shared via internet. But separating and mounting individual diatoms is still nearly as useful as ever. I used skin fat on target surface and seal hair as I thi...
by MicroBob
Thu Jul 02, 2020 4:52 pm
Forum: Specimens, samples and slides
Topic: New Diatom Project
Replies: 64
Views: 4390

Re: New Diatom Project

Hi Charles,
so the water contained diatoms until about the 45th minute?

Bob
by MicroBob
Thu Jul 02, 2020 4:48 pm
Forum: Specimens, samples and slides
Topic: Diatom selection experience
Replies: 38
Views: 2939

Re: A tip and a question about a slide of clean diatoms without silt

Hi Doron, thank you for the explanation! Building this ingenious setup must have taken quite some time. And there are probably few other designs that include a micrometer as well as Lego bricks! :lol: For my attempts at diatom arranging I used a simpler setup but was not that happy with it. It made ...
by MicroBob
Thu Jul 02, 2020 8:10 am
Forum: Specimens, samples and slides
Topic: Diatom selection experience
Replies: 38
Views: 2939

Re: A tip and a question about a slide of clean diatoms without silt

Hi Doron, congratulations to this nice setup! For some samples it probably is much more worthwhile to pick good frustules out than to try to clean the sample to a high grade. Do you use a sticky substance on the tip of your fibre? Is the fibre attatched to the objective and moves with the focussing ...
by MicroBob
Wed Jul 01, 2020 7:35 pm
Forum: Specimens, samples and slides
Topic: Diatom cleaning by incineration
Replies: 6
Views: 612

Re: Diatom cleaning by incineration

So what is diatom cleaning by incineration good? Find the answer yourself, here an image of a Tabularia diatom ensemble doing a half roll. :D
by MicroBob
Wed Jul 01, 2020 8:43 am
Forum: Pictures and Videos
Topic: Flagellate
Replies: 6
Views: 325

Re: Flagellate

Hi Jan, I can't watch the video due to mobile internet limits but I can recommend a suitable identification book. Since you are from the Netherlands you can probably read german to som degree? Here in Germany we use "Das Leben im Wassertropfen" as an amateur fresh water ID book. An older issue will ...
by MicroBob
Wed Jul 01, 2020 8:18 am
Forum: Specimens, samples and slides
Topic: Diatom cleaning by incineration
Replies: 6
Views: 612

Re: Diatom cleaning by incineration

Hi Doron, I recently read an article where they specifically compared inicineration and chemical cleaning for low silicified mediterranean sea diatoms. They found much less broken frustules after incineration cleaning. The research was probably directed towards identifying and counting and they prob...
by MicroBob
Tue Jun 30, 2020 9:55 am
Forum: Specimens, samples and slides
Topic: Diatom cleaning by incineration
Replies: 6
Views: 612

Diatom cleaning by incineration

Hi together, in the past I have cleaned diatom samples in a small oven at 450 degree C for 30 min. Frustule pairs and algae groups stay together and the frustule structure is visible very clearly. Now I'm experimenting with more compact setups with stainless steel plate, alcohol stove, micro gas tor...
by MicroBob
Mon Jun 29, 2020 6:46 pm
Forum: Pictures and Videos
Topic: Pediastrum algae after short incineration
Replies: 1
Views: 300

Pediastrum algae after short incineration

Hi together, I did some experimenting with my diatom cleaning by incineration. This time I used a small gas powered heat gun and directly applied the heat to the cover slip for a short time in short bursts from both sides. This was long and hot enough to char the organic matter, but it didn't burn e...
by MicroBob
Mon Jun 29, 2020 11:17 am
Forum: Pictures and Videos
Topic: I see stars - Asterionella diatoms in dark field
Replies: 7
Views: 750

Re: I see stars - Asterionella diatoms in dark field

It's a typical single 3W Cree LED, powered via USB cable over a 0,47Ohm resistor in row with a wire potentiometer. The USB power source is a Bosch GAA 12V with batteries from 2 to 6 Ah.
by MicroBob
Mon Jun 29, 2020 7:41 am
Forum: Pictures and Videos
Topic: Closterium
Replies: 4
Views: 976

Re: Closterium

Hi Jan,
that is a nice desmid you found there! They are also nice objects for Rheinberg illumination.

Bob
by MicroBob
Sun Jun 28, 2020 8:12 pm
Forum: Pictures and Videos
Topic: Closterium desmids
Replies: 5
Views: 505

Re: Closterium desmids

in fact I brought the mirror, it can be set onto the light outlet in the foot. I'm very used to built in lights so I want to try natural light with the Junior too.
by MicroBob
Sun Jun 28, 2020 8:05 pm
Forum: Pictures and Videos
Topic: I see stars - Asterionella diatoms in dark field
Replies: 7
Views: 750

Re: I see stars - Asterionella diatoms in dark field

With very small objects it is optical vs. digital magnification. But in most cases I too use max. the 1,6 setting.
by MicroBob
Sun Jun 28, 2020 7:02 pm
Forum: Pictures and Videos
Topic: I see stars - Asterionella diatoms in dark field
Replies: 7
Views: 750

I see stars - Asterionella diatoms in dark field

Hi together, here some Asterionella diatoms. Cleaned by incineration, milk carton dark field stop on light exit in the foot. 16:1 plan. I brought the Junior which proves very nice with bright battery illumination with 12V Bosch power tool battery and USB converter. What I miss from the Phomi is the ...
by MicroBob
Sun Jun 28, 2020 6:21 pm
Forum: Pictures and Videos
Topic: Closterium desmids
Replies: 5
Views: 505

Re: Closterium desmids

Photo made with the 40:1, oblique light. In the tips you can see crystals inside the end vacuoles. Closterium is found most frequent, some species are comparatively resitant to pollution. For the photo it turned into a nice even position. To me it looks quite healthy.
by MicroBob
Sun Jun 28, 2020 4:46 pm
Forum: Pictures and Videos
Topic: Closterium desmids
Replies: 5
Views: 505

Closterium desmids

Hi together,
here a couple of first photos from the micro life of the lake we have gone to.
Desmids tend to orient lengthwise in bright light as can be seen in one of the images.

Bob
by MicroBob
Sun Jun 28, 2020 7:19 am
Forum: Specimens, samples and slides
Topic: How do you clean your coverslips?
Replies: 5
Views: 1096

Re: How do you clean your coverslips?

Nice mountain, John!😂 This discussion on glass surfaces would sound like whitch craft to many people. But yes, this really is a topic and a very interesting one too. I had lots of problems with slides, even not so old, newly bought brand slides. The surfaces were etched, probably by moisture dissolv...
by MicroBob
Sat Jun 27, 2020 6:48 pm
Forum: Introduce yourself
Topic: Hello from Guam
Replies: 10
Views: 1349

Re: Hello from Guam

Wonderful image!
Typical stereo microscopes are used with non-correcting eyepieces and photo adaptations. But they generally don't acheive very good photo quality as the optics are designed for good free working distance, not resolution.

Bob
by MicroBob
Sat Jun 27, 2020 5:37 am
Forum: Microscopes and optics
Topic: Nikon Fluor Objective Full of Oil!
Replies: 15
Views: 1523

Re: Nikon Fluor Objective Full of Oil!

Just one little drop more will do no harm! :lol:
by MicroBob
Sat Jun 27, 2020 5:35 am
Forum: Microscopes and optics
Topic: Best DIC options?
Replies: 57
Views: 4161

Re: Best DIC options?

The condenser doesn't look like my one and it is probably newer. My condenser has the older slightly domed metal top cover and no dark field port. I'm quite sure that my components were originally sold together as system 2. System 3 usually come with the condensers with plastic top cover that look n...
by MicroBob
Fri Jun 26, 2020 8:20 pm
Forum: Microscopes and optics
Topic: Best DIC options?
Replies: 57
Views: 4161

Re: Best DIC options?

I think I have read that there were condensers with different numbers of DIC prisms for DIC Version 3. DIC 1 must have started around 1965 in small numbers. 160mm was no longer fashionable around 1985. That was quite a span of time for just three versions of a new and popular conrast system, so I wo...
by MicroBob
Fri Jun 26, 2020 5:14 pm
Forum: My microscope
Topic: Flat Field Dynazoom Operational
Replies: 14
Views: 2548

Re: Flat Field Dynazoom Operational

Radazz wrote:
Fri Jun 26, 2020 11:05 am
the single knob version.
There were two single knob versions: Either trinocular head and no zoom or binocular haeada and zoom.

The binocular tube is comparatively easy to dismantle and clean. This might improve you instrument a lot.

Bob
by MicroBob
Fri Jun 26, 2020 4:34 pm
Forum: Microscopes and optics
Topic: Best DIC options?
Replies: 57
Views: 4161

Re: Best DIC options?

Hi Glen,
this text by Spike Walker is probably the most valuable piece of information on the two old systems as it names the serial numbers of the suitable objectives. And I can attest that the serial numers range really has to adhered to.

Bob
by MicroBob
Fri Jun 26, 2020 10:59 am
Forum: Microscopes and optics
Topic: Best DIC options?
Replies: 57
Views: 4161

Re: Best DIC options?

Hi Pete, according the two first Zeiss DIC-Systems: The first one was the very first great grandfather of DIC systems and the numerns are probably small. The intermediate tube for the small stands had a little less height. There are rumors that a slider "I" existed. It was intended for the older Pla...
by MicroBob
Thu Jun 25, 2020 9:04 pm
Forum: Microscopes and optics
Topic: Best DIC options?
Replies: 57
Views: 4161

Re: Best DIC options?

Hi together, there were actually three Zeiss 160mm DIC systems. The two first look quite similar but don't mix well. Spike Walker describes these three systems and mentions serial numbers of compatible objectives. A while ago I posted a document on how to assemble and set up the second system. The f...