Photomicrography, past meet present

[belgiumreporter]

Because i will be needing to do a lot of microphotography in the future, it was time to recapulate some of the things i've learned in a distant past.

So i made a set up with some gear i still had laying around and coupled it with the digital age. I used my old school Olympus microscope and mounted the Pentax K-x digital on it with a pentax M42 microscope adapter made to fit on the K-x with a m42 to K mount ring.

To my amazement things went very well and it's a world of diffrence compared to the old days of film. The monocular Olympus did just fine i could easily focus the image on the display of the K-x ( no need for a trinocular set-up). Exposure was easy to, a bit of trial and error to get it right, but once set no further problems occured.

I just tried a flat preparation of the wing of a damselfly and got just about everything in focus at a 100x magnification. But i won't be photographing damselflys, it will be mineralogy specimens for witch i'll be needing more depth of field, once again digital processing will come to my aid in the form of focus stacking software.

Knowing all this i'll be ordering a proper Nikon microscope adapter to use on my more suitable Baush & Lomb mineralogy microscope, now that i'm confident i will be up to the task.

The set up :



Main vein of the wing of a damselfly.( made with the above set up)

[barbarian]

Just beautiful work. Have you ever participated in Nikon's Small World competition?

[paulhofseth]

Please excuse my ignorance, but it looks as if you use an ordinary (or a flat-field macro) coupled to the ocular.

I have an ancient Leica (rebtranded AO\ B&L ) variable magnification "Greenhough type" stereo loupe, for looking at small things, not anything as powewrful as a microscope, but with 10-70x magnification and proper depth perception, plenty for my use. What can be done to relay the image up to a camera? ( I am aware of the lomg discontinued amd unavailable "Third tube" solution)

According to the device description, the Leica oculars are designed to compensate for residual aberrations in the objectives, so they should presumably be left in place.

p.

[belgiumreporter]

Dec 14, 2017 16:01:07 GMT -5 paulhofseth said:

Please excuse my ignorance, but it looks as if you use an ordinary (or a flat-field macro) coupled to the ocular.

I have an ancient Leica (rebtranded AO\ B&L ) variable magnification "Greenhough type" stereo loupe, for looking at small things, not anything as powewrful as a microscope, but with 10-70x magnification and proper depth perception, plenty for my use. What can be done to relay the image up to a camera? ( I am aware of the lomg discontinued amd unavailable "Third tube" solution)

According to the device description, the Leica oculars are designed to compensate for residual aberrations in the objectives, so they should presumably be left in place.

p.

I'll try to answser your questions with the little knowledge i have on the matter. The set up shown in the picture is no more than the microscope with a 10x microscope lens in place, theres no occular in place and the shot was taken straight through the tubus of the microscope with the aid of a pentax microscope to camera adapter.

Now as far as i know in these kind of set ups an occular would only add glass in the light path and most likely will not help in improving the image quality, but then again if Leica claims their occulars will reduce residual aberrations, who am i to question this? i don't have any experience with such a set up.

With binocular microscopes or loupes i think the only way to relay the image to the camera is to use one of the tubes to mount the camera, the other one to view the subject,that is if the camera in such a set up wont be in the way of using the second tube.In film days that would be quite some problem but today with camera's wich have live view i think it is easier to work with as you can immediatly see what the camera is registering.

Third tube or trinoculars are the best solution, but yes they are (very) expensive, i can not afford a 10.000€ trinocular horizontal mineral examination microscope for what i would use it. We do have them in our lab if ever i should really need one. Meanwhile i am experimenting with a "microscope less" set up wich will get me to a max of 16x, enough for minerals, not enough for diamond examination( but that is done by my wife in the lab and i have no need to do this at home).

This set up consists of a nikon PB-5 bellows and a BR-2 reversing ring on wich i mount the nikkor 20mm, at full bellows extension this gets me a 16x magnification.

For the moment the set up is very unstable but suitable as a proof of concept.

The set up:



I used it to get a closer look on this piece of Siliciumcarbide (carborundum).



At 16x you can clearly see the "colourfull spots" are in fact corund cristals with their trigonal structure. Focus stacking would enable me to get a lot more depht of field, but as said, this set up is to unstable to attempt it.

[hansz]

Hm, carborundum, or Silicon Carbide (SiC), is generally a man-made chemical substance. When found in nature it is called moissanite and is mainly found in meteorites. Is this Polish piece genuine or man-made??
Hans

[belgiumreporter]

Dec 21, 2017 7:02:04 GMT -5 hansz said:

Hm, carborundum, or Silicon Carbide (SiC), is generally a man-made chemical substance. When found in nature it is called moissanite and is mainly found in meteorites. Is this Polish piece genuine or man-made??
Hans

Most likely man made, i'm not shure if there are any kimberlite deposits ( in wich the carborundum is most likely to occur)  to be found in Poland, even then it would be a rare find that you probably won't find for the price i paid for this specimen.

[belgiumreporter]

Because it dosn't allways have to be minerals:
I just did an interesting experiment, i was allways wondering why i had trouble shaving with cheap no name shaving knives, well i guess here's the awswer:

No name 5 blade shaver after two shaves: the cutting edge is very rough and by the look of the how they are finished have allways been so.Rust stains are already developping
Due to the poor cutting power the blades get easely clogged up wich makes a smooth shave even more difficult.



Gilette fusion 5 blade, after some 10 or more shaves: the polished cutting edges of the blades are still sharp and undamaged.


Now if gilette would be so kind to send me a life time supply of mach5 shavers for doing this test...:-)))

[belgiumreporter]

While we are at it, here's a close up of a slice of iron meteorite, where you can see the pattern formed by the Widmanstättenstructure. Sadly i haven't got a sample with inclosed pallasite (thought i had one though), wich reminds me i'll have to get one.

[hansz]

Dec 22, 2017 2:42:33 GMT -5 belgiumreporter said:

While we are at it, here's a close up of a slice of iron meteorite, where you can see the pattern formed by the Widmanstättenstructure. Sadly i haven't got a sample with inclosed pallasite (thought i had one though), wich reminds me i'll have to get one.

You want a pallasite? That will cost you serious money... We, at the Geologisch Museum Hofland at Laren (NH) Netherlands, have one, and paid a special price, being a museum, but still nearly a 4 digit figure in euro...

Hans

Next Tuesday I will be at the museum and take a photograph of it.

[belgiumreporter]

It isn't easy to reproduce the true beauty of an opal in an image. Depending on how light strikes it, or the type of light, the appearance of the opal can change dramatically.
With short focal lenght macro lenses i have to come to close to the subject to have some place left for my light source, so i used my "old" micro nikkor 200mm wich left a confortable working distance between subject and front element of the lens.

The same opal, i used the same light source, but directed from a diffrent angle...


The wonderfull patterns on a good quality koroït opal.


You don't need the latest in AF macro lens technology to get good results as in this case the AI micro nikkor 200mm has served me well.

[belgiumreporter]

Here's a fire agate , i think it's clear why they call this fire agate...


And here's a rough diamond octaëder


Enjoying myselve while the camera set up is still available...

[belgiumreporter]

Inpurities in Zaïrese diamond seen in transmitted light, (iron, carbon and a crevice) made with the Olympus/pentax setup at 100x stack of 20 shots.

[belgiumreporter]

I was able to buy a Olympus ECEBi binocular microscope at a fair price, so it is now my new microscope set up. It came with build in illumination and a coaxial stage, wich made it cheaper than upgrading my monocular Olympus microscope.

Ive looked into the problem of using a specific ocular for photography, but turns out i dont need one for my type of photomicroscopy as it is mainly used to correct ca.(fringing) that occures with certain objectives and to photograph the complete (projected) image if youre using smaller than FX sized camera sensors.

More than 100x is useless for me and the only thing at this moment i would need is a 5X objective (to get to 50x) lower magnification i can get with my Bauch and Lomb 10 to 40x stereo microscope or bellows straight on the camera.

[hansz]

François, I still owe you the picture of our palasite...

palasiet by Hans de Groot, on Flickr

Hans