buying a microscope

I was hoping to see what microscopes any of you use and any recommendations on which microscope would be best for all around observing and measuring the presence of microorganisms in soil, compost, and compost tea. I am interested in tinkering with tea recipes and wanted to also find out if there were any particular models to avoid and perhaps any to seek out. Also I don't plan on spending too much, maybe a couple hundred bucks at most. Thanks!

To be able to see the microorganisms we want in our soil well enough to be able to distinguish the good from the bad, you will need a minimum of 2500 X.

Bare Minimum

1/2 step up from bare min.

easier to use

good basic kit

To really see the organisms well you want binocular, the last one is pretty good without getting in the 300 dollar and up range plus it comes with slide prep kit and a book on how to use the microscope.

Redhawk

It was my birthday recently and I'm thinking of buying myself a present of a microscope. I'm interested in learning more about soil biology, and maybe quantifying the improvement I make in the soil in my Natural farming area. I've had a little look online and there a couple of nice looking bit of equipment on ebay. The question is do I go for the cheaper, new one, or the second hand possibly better quality one.


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The new one is a "Swift 380T Trinocular Compound Microscope 40x-2500x Wide-Field 10x 25x LED Base" It implies that it comes with both 10x and 25x eyepieces, and 4X, 10X, 40X(Spring), and 100X (sping/oil) objectives. At a shade under £300 it seems ideal.

The alternative is this one:

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Which is an "Olympus Microscope BH2 With 2 Plan and 2 D Plan Objectives and widefield eyepcs". The eyepieces are 10x and the objectives are 4x, 10x, 40x, 100x. This one is a second hand machine - the seller claims to be upgrading. They say the ojectives are a mix of plan and d plan; I'm not sure what this means. There is space for another objective too. The asking price is £484, but open for best offer too.

Both are trinocular machines. I'm leaning to the Olympus at the moment, although it is more expensive, because I thinks the quality of the optics is likely to be better. However Dr Bryant Redhawk seem to imply that a 1000x isn't really a big enough magnification. I had a quick look for eyepieces and there don't seem to be many around for the Olympus at the moment. Are they likely to interchangeable from other makers or is it not really neccessary to get that great a magnification? I think Elaine Ingham implies that 400X is adequate for most soil analysis.

Which should I go for (bearing in mind I'll need equipment - slides etc. as well) or should I wait for a different machine set up?

With 10X on the oculars and a 100X objective, that 1000X should be sufficient...I would confirm that the 100X objective is "oil immersion" since that seems to be crucial for optimal clarity of the image.  If you go to "Google Images" and type key words "Gram stain bacteria 1000X" you will find many images at that magnification.....many bacterial species can be observed without needing higher.  Also see   https://www.ruf.rice.edu/~bioslabs/BIOC318/view_Gram_stain.asp   for a review of Gram staining, although I suspect Redhawk posted one as well.

Fungal spores and hyphae are larger and do not need such high magnification, so you should be okay.  In general, I've liked the Olympus equipment I've worked with.  Not quite as top-end as Zeiss, but also does not have Zeiss's price tag.  Also would stay with Olympus between the two that you are looking at since Oly has a deep history in microscopy and you should be able to find parts/objectives easier on the second-hand market.  Looks like a US reseller that is accessible to the general use market sells new sets of Olympus objectives.....the Plan Achromatics are pretty standard use in biology and the 100X is oil immersion.    https://www.edmundoptics.com/f/olympus-plan-achromatic-objectives/14535/

Good luck!

Nancy Reading wrote:

The alternative is this one:

source
Which is an "Olympus Microscope BH2 With 2 Plan and 2 D Plan Objectives and widefield eyepcs". The eyepieces are 10x and the objectives are 4x, 10x, 40x, 100x. This one is a second hand machine - the seller claims to be upgrading. They say the ojectives are a mix of plan and d plan; I'm not sure what this means. There is space for another objective too. The asking price is £484, but open for best offer too.

Both are trinocular machines. I'm leaning to the Olympus at the moment, although it is more expensive, because I thinks the quality of the optics is likely to be better. However Dr Bryant Redhawk seem to imply that a 1000x isn't really a big enough magnification. I had a quick look for eyepieces and there don't seem to be many around for the Olympus at the moment. Are they likely to interchangeable from other makers or is it not really neccessary to get that great a magnification? I think Elaine Ingham implies that 400X is adequate for most soil analysis.

Which should I go for (bearing in mind I'll need equipment - slides etc. as well) or should I wait for a different machine set up?

Olympus is a high quality instrument. Since it has an open objective, you can add a high power one when you desire to check bacteria. 400x to 1000x are good for things like springtails, fungi, etc. The 2000 + magnification is for bacteria, I like 2500x for those. The extras will total less than 50 pounds. Box of 100 slides, cover slips and gram stain should only run in the 20 pound range.

Redhawk

Thank you both for your replies. I checked and the 100x objective is with oil, so that would be OK. I think I'll go for the Olympus. I just noticed it is actually an auction, so I may not get it....(no bids yet though)

Aside from the strength of the magnification.
Isn't there "dark field" viewing and stuff like that?

craig howard wrote:Aside from the strength of the magnification.
Isn't there "dark field" viewing and stuff like that?

Dark field requires a special light source, there are also other light sources like polarized. Each adds to the cost of the instrument. Each type has specialized purposes like mineral inspection etc. For soil organism use you only need a good white light source, which is the standard that comes with most microscopes. Dark field scopes tend to start in the 2000.00 US price range and can go up to 12,000.00 US or even higher in costs. The Leica, Ziess, Nikon, are very high priced because of brand name and quality of lenses. These can be over 30,000.00 US

Redhawk

Thanks, so a dark field light source isn't something that can normally be added later in an upgrade.
It needs to start out as a dark field microscope.

craig howard wrote:Thanks, so a dark field light source isn't something that can normally be added later in an upgrade.
It needs to start out as a dark field microscope.

Speaking from experience, you can make a hack-job darkfield microscope out of a lightfield microscope by turning off the light from below and adding a light from above. Ideally a ring-light on the objective, but in a pinch I have also had success with fibre optic lights pointed at the slide. It causes more glare than 'proper' darkfield set-ups, but did the job well enough for what I was doing. Wouldn't recommend it for extended microscope use as it is less friendly on the eyes.

Thanks everyone for your advice - I won the Olympus!!! So hopefully that will be with me in about a week. I'll start a new thread on a beginners adventures in soil microscopy once I'm up and running.