Petroscope

Here you can discuss all microscopy-related accessories and equipment (microtomes, filters...)
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Glot
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Joined: Thu Oct 17, 2019 7:23 am

Petroscope

#1 Post by Glot » Wed Jan 15, 2020 10:42 am

I know it's not microbe related but someone might know. I plan to buy a cheap petroscope for hobby use. I am wondering if there is any reason why they can't be used as a general purpose compound microscope? There a is a cheap Indian one that seems to have reasonable specs for the price. Of course low general quality.

MicroBob
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Re: Petroscope

#2 Post by MicroBob » Wed Jan 15, 2020 11:21 am

Can you post a link of what you have in mind?
Do you think about a petrographic microscope?

Bob

microb
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Re: Petroscope

#3 Post by microb » Wed Jan 15, 2020 3:38 pm

If you are looking at Radical, I'd avoid them unless you know someone that bought a particular model and was somehow ok with it.

I bought a "Radical 1500x Trinocular Steel Aluminium Alloy Metal Testing Lab Metallurgical Reflected Light Microscope with Polarizing and XY stage" off of Amazon in 2018, and it's not very good. A beat up Nikon or Olympus off of ebay would be way better. Regarding the Radical, I used an eyepiece camera for it. Months later I hooked up a camera to the trinocular vertical port, and that's when I found out the slider did not work. Taking it a part, the sliding prism slams into the housing and half-way blocks the light path. Plus the prism was chipped with glass inside. Clearly their QA just pulled it harder than I was willing to. That's when I found out they do not support their warranty. I sent pictures, but they said just loosen screws to readjust. I wanted to return, but they said it's been too long. I wanted a replacement head, they said adjust the screws. I wrote back that that doesn't work. But after a three months of nonsense, I decided to drill some holes reset the prism and donate it. But if someone asked, I vowed to warn them. Just let that company pass away into history sooner than later.

Also the "steel aluminum" frame shakes in the image with very little pressure in trying to focus. Plastic coin cameras with their metal tube pole jammed into a plastic base are just as good in that case. Maybe Amscope makes better cheaper stuff. I don't know. I'd buy a used Olympus or other name brand instead. There's lots of people out there to answer questions and help getting different cameras working even for the oldest of microscopes from Nikon or Olympus -- or or the others Zeiss and Leica and so on.

Ted

Glot
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Re: Petroscope

#4 Post by Glot » Sat Jan 18, 2020 7:14 am

Yes Bob. Just terminology.

Glot
Posts: 65
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Re: Petroscope

#5 Post by Glot » Sat Jan 18, 2020 7:24 am

Thanks Ted. I am not sure of the brand but will check. I have found it very difficult to find second hand ones and I would be buying off a photo. I have been warned away from ex school or uni ones unless I am prepared to see d time and money on them. Apart from quality,as you warned, i was concerned some technicality of the objectives or something. I guess they use them for reflected light as well so should be okay for various slides on a basic level. I'd love one of everything as we all would.
One model I was browsing is an RPL3B. Doesn't say brand but the R makes me think Radical. I was just initially looking at something like this but not if its false value. I only want to play around but don't want to get frustrated by low quality.

Glot
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Joined: Thu Oct 17, 2019 7:23 am

Re: Petroscope

#6 Post by Glot » Sat Jan 18, 2020 7:45 am

This gives a lot of info as suggested further on. The hyperlinks in the text are worth look in at.
https://lavinia.as.arizona.edu/~mtuell/ ... ophot.html
Last edited by Glot on Sat Jan 18, 2020 8:26 am, edited 2 times in total.

Scarodactyl
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Re: Petroscope

#7 Post by Scarodactyl » Sat Jan 18, 2020 7:45 am

It is hard to find used geological scopes. Geologists just love their scopes and hold onto them tightly--part of that is that the standard loadout is still standard decades later even for research, not constantly evolving with new vital features like fluorescence and confocal stuff.

Petrographic scopes should be fine for other usage too. Some use specialized pol objectives but these are just made with low strain glass which doesn't affect their use in non-polarized light

A reasonable stopgap might be to get a Nikon labophot and one of the medical polarizing kits (used primarily for differentiating gout and pseudogout) which are sometimes available inexpensively. This gives you a polarizer, analyzer and gypsum plate, though no bertrand lens. Eventually you can either also get a rotating stage and a petrographic module to complete the set, or if you find a complete petrographic scope you can sell the labophot off for about what you paid or more if you bought well.

Glot
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Re: Petroscope

#8 Post by Glot » Sat Jan 18, 2020 8:37 am

I have decided that a cheap apparatus is okay for low magnification stereo, once I go higher magnification, quality will play a big part. Buying second hand from a reputable dealer in the USA or Canada isn't out of the question.

Glot
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Joined: Thu Oct 17, 2019 7:23 am

Re: Petroscope

#9 Post by Glot » Sun Jan 26, 2020 5:36 am

Have been searching the WWW. I think any quality petroscope will be beyond my financial limits. Even second hand, they are pricey. For the new price of the ebay one, they must be low quality but I surely they are useable? I haven't found one yet, but there could be an Australian reseller which would give me some consumer protection.
I am happy with my $315 zoomable stereo. A professional would chuck it in the bin but does what I want. Only real negative is no very fine focus. Almost impossible to focus well at 90X. I rarely go above 45X. I am thinking maybe the cheap pet might fall in the same category. Ted's remarks are well noted. If anyone else has had experience with one,I'd love to hear.

jb89
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Re: Petroscope

#10 Post by jb89 » Tue Feb 04, 2020 9:50 pm

I occasionally see older(very old) petro scopes for less than $200, generally LOMO or black enamel ones from the early 1900's I would think.

I am sure they are good enough for hobby use.

Do you have a way to cut thin sections? petrographic samples get expensive fast if you have to have someone else make them for you

I'm a geology student but use my scopes for biologic specimens quite frequently, looking at live specimens is just super interesting to me. I have recently upgraded from a Leitz SM-LUX-POL to a Zeiss Universal and plan to add a camera and darkfield accessories while only using my POL objectives until I can afford to upgrade to a dedicated set of high performance/corrected objectives.

If you want a very cheap/not high performance method for viewing specimens in polarized light there instructions that use polarization filters you can use to make a field expedient low and fixed power 'scope' and I can try and find those instructions for you if you can't find them

Glot
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Joined: Thu Oct 17, 2019 7:23 am

Re: Petroscope

#11 Post by Glot » Thu Feb 13, 2020 8:25 pm

Thanks jb 89. I have found a couple of decent second hand ones from a commercial seller for 1800. I am making my own thin sections. I can get a set of about 20 standard ones for teaching for about 400. They charge about 60 to 80 for a standard custom one. My stereo goes up to 90x. I have polarisers on order to play with that. I would like a rotatable stage plus plates rather than just going for a biological and adding polarisers.

Glot
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Joined: Thu Oct 17, 2019 7:23 am

Re: Petroscope

#12 Post by Glot » Thu Feb 20, 2020 5:50 am

This will make a few chuckle. Got my polarising film. Cut and installed both. Couldn't get much extinction. Scratching my head. Then had an idea. I have an acrylic plate above the bottom polariser. Simple. Remove that and all fixed.will replace it with glass.

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