MicrobeHunter.com Microscopy Forum

A few years ago I bought a fairly large front surface mirror on Ebay for about $20, if memory serves. Using a hardware store glass cutter I cut a new 45 degree mirror for the internal illuminator in one of my A/O 4 Series stands. The reflecting surface on the old mirror was in bad shape. The first a...

The method shown is the same as I've seen in old microscopy books... After a look in the referenced book: Where do you find double razor blades today? I think they are an extinct species, at least as shaving is concerned... I think I saw some double edged blades in the local Walmart not too long ag...

John B. knows a lot more about this subject than I do, but here's a link to look at until he gets back to you. I tried some freehand sectioning many years ago with limited success. With lots of practice one can get a few good ones suitable for making permanent slides. They will be much thicker than ...

Since the transformer primary winding, which connects to the mains, needs alternating current to function, you'll need to bypass the transformer and connect 6 volts DC directly to the dimmer unit or bulb. If the dimmer unit is solid state electronic, you'll probably need to connect the DC supply dir...

Having long been interested in ancient life, I seem to recall reading that testate amoebae are an ancient group, predating the Cambrian. A little Googling turned up a scientific paper about exceptionally well preserved testate amoebae in rocks that predate the Cambrian and even the Ediacaran. These ...

The black ones were produced for many years, into the 1950s I think. I have one also.

This morning I found another online Spencer catalog pdf from 1914 that shows the 820 as well. I think it's based on the Minot design, which was patented in the late 19th century.

Flickering can be caused by the illumination intensity of a light source changing with each cycle of alternating current from the mains. Our eyes don't notice it, but a video capture device with a fast "shutter speed", for lack of the proper term, can record it. Incandescent lamps, fluorescent lamps...

Oops, I intended my reply to MikeA, as it seemed he might want to section fresh or preserved plant stems.

That's what I get for assuming...

The Venerable Spencer/AO/Reichert/Cambridge/Leica 820 turned 100 years old last year or a bit before. Here is a link to a Spencer Lens Company catalog from 1917 showing it along with all their other products. This file can be downloaded. I tried to attach it but it was too large. :( https://books.go...

Many years ago a special blade holder was made for the 820 that held the blade at an angle for sectioning celloidin that might work for fresh plant stems. The part number was 825. Good luck finding one, though. If you have metal working tools you might be able to cobble something together. I attache...

The 100X oil immersion was useless, producing a fuzzy image only at the edge of the field in the 2 o'clock position. I guess that would be bad optical centering. 2000 hey? Well that should have been an older one I'd imagine. Over the next couple of days I'll test the oil obj on mine and post a pic ...

A nice looking pair! I'm curious about the objective on the 1902 model, looks like about 10X. Is the focal length marked in inches or millimeters? I think Bausch & Lomb switched from inch to metric measurements around 1900 or thereabouts. I have an objective that looks like that one, marked 2/3-inch...

I have one just like that, or nearly so. I bought it from a nationwide discount tool company named "Harbor Freight Tools" around the year 2000. Harbor Freight no longer sells microscopes like that. I think the objectives are 36mm parfocal, and I don't believe they're coated. For awhile several years...

Those are great images! Thanks for showing us what those objectives can do. I've tried 33mm LOMO achromats on my A/O 4 Series stand with good results, and may eventually try one of their water immersion lenses.

This might be a good addition to anyone using an A/O or Spencer Lens Co. 160mm scope. A couple of years ago I bought an older version of this objective with a very low serial number in the 11,XXX range. I'm guessing it was made around 1905 give or take a few years. No one wanted to take a chance on ...

Hi Mike,

That's an impressive array of equipment! A/O Spencer and the Spencer Lens Company have been very good to me for equipping my bench at low cost, as my hobby budget isn't very big.

I hope this isn't misinformation, and someone please correct me if it is. My memory isn't the greatest anymore. In a microscopy book published around 1900, and I'm not sure which one it was, it was recommended to place dark field and oblique illumination stops as close to the condenser iris diaphrag...

It might. Before the Spencer Lens Co. was bought by A/O, Spencer microscopes started using a fork mounted condenser. The first fork mount was smaller than the later one. The later fork mount should be the same size as the 4 Series. Do you have any way to measure the groove for the fork mount on the ...

OK, the line drawings are good. This is a good copy. Lots of good info in it, although the relations between the families of organisms have changed, some of them a great deal. But good for identification.

If you have a fast connection and lots of hard drive space, you can download this: https://archive.org/download/in.ernet.dli.2015.7374/2015.7374.Fresh-Water-Biology-1918.pdf 178 megabytes. I bought a hard copy many years ago. Your protist is probably in there. The only problem is many organisms have...

Thanks for the ID and the link. There a few of those in some permanent slides I made of the surface film of a hay infusion.

Very interesting images. I like the last one especially.

Please don't be offended, but they look kind of other-world science fiction like with that illumination. Maybe like the brains of some alien life forms.

Amazing photos! Under ordinary bright field they would look kind of plain by comparison.

How long is the tube length of your microscope then? As far as I know these old optical glasses were sometimes not perfectly resistant against ageing. I have had old (a couple of decades) packages of slides that had surfaces that were not good any more. I remember a value called hydrolysis resistan...

In the late 1890s B&L was making objectives for both 250mm and 160mm tube lengths. During that time, the objectives were marked for tube length. If yours is a 160mm objective, and if you have a 160mm scope, you can have fun looking at objects with that objective. I have a similar objective, 2/3" and...

Hi Rick, have you tried to take pictures with a high power oil immersion lens? I once had a "Rollei" camera quite similar to yours. With this camera you got nice pictures with weaker objectives. When you used strong objectives you got concentric rings within the image. They result from the use of c...

A little piece of trivia, since natural history is one of my interests, a quote from the Wikipedia article on red algae: Fossil record One of the oldest fossils identified as a red alga is also the oldest fossil eukaryote that belongs to a specific modern taxon. Bangiomorpha pubescens, a multicellul...

Thanks, zzffnn. The camera chooses its own shutter speed. I don't have any direct control over that. The drill is to depress the shutter button half way and the camera will indicate on the viewing screen when it's ready to take the picture. Depressing the shutter button the rest of the way will take...

This is an image I uploaded to the Yahoo user group back in 2012. Can't believe it's been that long since I did any photomicrography. The diatom is Staruoneis Phoenocenteron from an 8 form test plate made by Klaus Kemp in 2004. Magnification is 645X. Looking back on it now, I don't understand why I ...

Welcome, Rick! What are your other hobbies :mrgreen: please share more with us. My other hobbies are: collecting music and seashells, photography, water sports, nature, world culture and cuisine. My other hobbies are film photography, mostly large format photography the last time I was active. Have...