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Muscaria7
The Budding Mycologist
Registered: 01/17/09
Posts: 83
Loc: Texas
Last seen: 11 years, 7 months
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Question on Microscopes
#10259495 - 04/29/09 11:01 PM (14 years, 10 months ago) |
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Hey Guys, So Im looking to buy a microscope for better identification of wild mushrooms, I want one that is capable of seeing spores and mycelium well enough, but not excessively expensive.
I found one on ebay that hooks up to your computer, is it good enough for what I want to do with it?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=350190328516
-------------------- Life sucks, but coffee is pretty good.
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Alan Rockefeller
Mycologist
Registered: 03/10/07
Posts: 48,358
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Re: Question on Microscopes [Re: Muscaria7]
#10259519 - 04/29/09 11:07 PM (14 years, 10 months ago) |
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900x is pretty good. I wouldn't expect much image quality from a 640x480 camera, in fact most people who get these say they are crap. You might be able to see something though.
You would be better off with this one:
http://store.amscope.com/b490a.html
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Muscaria7
The Budding Mycologist
Registered: 01/17/09
Posts: 83
Loc: Texas
Last seen: 11 years, 7 months
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Ok, thanks.
How much Magnification do I need to see Spores and Mycelium Clamps and things?
-------------------- Life sucks, but coffee is pretty good.
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Alan Rockefeller
Mycologist
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Re: Question on Microscopes [Re: Muscaria7]
#10260042 - 04/30/09 12:51 AM (14 years, 10 months ago) |
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1000x. 1600 works well too.
Also its important to have a an eyepiece with a reticule for measuring the spores.
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ToxicMan
Bite me, it's fun!
Registered: 06/28/02
Posts: 6,725
Loc: Aurora, Colorado
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Re: Question on Microscopes [Re: Muscaria7]
#10266314 - 04/30/09 11:06 PM (14 years, 10 months ago) |
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I'm only going to disagree a little.
1000x (or more) for seeing things like ornamentation on spores. I do probably 90% (or more) of my microscopy at 400x. It's certainly good enough for spore measurements and seeing the shapes of the spores, observing cystidia, or even looking for incrustation on hyphae.
You should get a microscope with a good oil immersion objective for those times when you'll need it.
Happy mushrooming!
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Strophariaceae
mycologist
Registered: 02/02/04
Posts: 109
Loc: Marvelous Marin County, C...
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Re: Question on Microscopes [Re: ToxicMan]
#10269007 - 05/01/09 01:40 PM (14 years, 10 months ago) |
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As I've pointed out many times, seeing greater detail is not about magnification, its about resolution (as measured by the NA of the objective), and believe me, that's not just some abstract technical BS.
If you have a 100X/1.25 NA objective you will absolutely not be able to resolve anything at all better at 1600X total magnification than at 1000X magnification. All you get with piling more magnification on is empty magnification. Think about taking a 10X10 pixel jpeg and blowing it up to make it bigger - all you get is bigger pixels. Same idea - the objects viewed through a lens aren't pixellated, obviously, but the image will simply be larger and fuzzier.
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Alan Rockefeller
Mycologist
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Quote:
If you have a 100X/1.25 NA objective you will absolutely not be able to resolve anything at all better at 1600X total magnification than at 1000X magnification.
Might be easier to measure though.
Thats why I use 2000x instead of 1000x. The reticle grid is the same size but the images are twice as big.
What is the ideal NA to have on the 100x oil immersion objective?
I just got a zeiss .90 NA condenser in the mail yesterday. What is a good objective to go with that? (160 mm tube length)
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Strophariaceae
mycologist
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Posts: 109
Loc: Marvelous Marin County, C...
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Quote:
Alan Rockefeller said:
Quote:
If you have a 100X/1.25 NA objective you will absolutely not be able to resolve anything at all better at 1600X total magnification than at 1000X magnification.
Might be easier to measure though.
Thats why I use 2000x instead of 1000x. The reticle grid is the same size but the images are twice as big.
That's probably true. Where "effective magnification" becomes "comfortable magnification" for a given resolution is subjective, but for measuring spores, that's definitely on the larger side.
Quote:
What is the ideal NA to have on the 100x oil immersion objective?
Well, as high as you can find, really. 1.25 NA achromat is what you'll find on most 100X oil lenses, and that's adequate for most fungal taxonomy. But you'll get even more resolution out of a 1.3 or 1.4 NA objective (these are apochromat or plan apochromat lenses). More resolution still if you use such a lens with an oil immersion condenser, though that's kind of messy to set up and clean later.
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I just got a zeiss .90 NA condenser in the mail yesterday. What is a good objective to go with that? (160 mm tube length)
Again, 1.25 NA is OK, but you can go higher if you want. Effective resolution in brightfield microscopy: if the objective NA is less than or equal to that of the condenser, then effective NA is equal to that of the objective. If the NA of the objective is greater, than effective resolution is an average of the condenser and objective NAs. So you still get additional resolution from a higher NA oil objective, but it doesn't scale up as dramatically than if you were using an oil immersion condenser.
Unless you're planning on using oil immersion with your condenser, 0.90 NA is the condenser you want. That's because they're designed to focus accurately where there's an air gap between the condenser and the slide. Higher NA condensers sometimes work OK with air gaps, but are designed to focus best under oil immersion.
BTW, did the Zeiss condenser actually fit on your scope? The old Zeiss condensers (at least the West German brand, as opposed to Zeiss Jena) had a "dovetail" design that only fit onto Zeiss stands.
So how does any of this apply practically? Well, for most fungal taxonomy, a 100X/1.25 NA condenser is often the highest magnification/resolution combo you need. However, there are some species that have certain feature where you need the extra resolution. The germ pore in some Pholiota species is a notoriously small and hard-to-resolve object. Many of the species descriptions and, I think, keys in Smith and Hesler's Pholiota monograph actually specify that the germ pore in that species is resolvable only at 1.4 NA. (Aspiring pholiotologists take note!)
Also, if you're doing high-end microphotography, having added resolution is of great benefit.
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Strophariaceae
mycologist
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Loc: Marvelous Marin County, C...
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Re: Question on Microscopes [Re: Muscaria7]
#10270423 - 05/01/09 08:03 PM (14 years, 10 months ago) |
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Quote:
Muscaria7 said: Hey Guys, So Im looking to buy a microscope for better identification of wild mushrooms, I want one that is capable of seeing spores and mycelium well enough, but not excessively expensive.
I found one on ebay that hooks up to your computer, is it good enough for what I want to do with it?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=350190328516
What you're looking at in the eBay posting is a toy microscope for kids. It might work reasonably well at low magnifications, but I seriously doubt it's going to resolve much of anything at higher magnifications. If you buy this to see fungal micromorphology, you're wasting your money.
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Alan Rockefeller
Mycologist
Registered: 03/10/07
Posts: 48,358
Last seen: 7 days, 20 hours
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Quote:
1.25 NA achromat is what you'll find on most 100X oil lenses, and that's adequate for most fungal taxonomy. But you'll get even more resolution out of a 1.3 or 1.4 NA objective
Will my .90 condenser drive 1.3 or 1.4 objectives well? Or should I get a 1.3 or 1.4 condenser for those?
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Muscaria7
The Budding Mycologist
Registered: 01/17/09
Posts: 83
Loc: Texas
Last seen: 11 years, 7 months
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Sorry to bring this back up, but I found this one on amscope and wondered if it would be capable of what I need it for.
http://store.amscope.com/m200-b.html
Like I said, I am kind of short on money, and have a fairly specific use for it.
-------------------- Life sucks, but coffee is pretty good.
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Alan Rockefeller
Mycologist
Registered: 03/10/07
Posts: 48,358
Last seen: 7 days, 20 hours
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Re: Question on Microscopes [Re: Muscaria7]
#10286798 - 05/04/09 09:16 PM (14 years, 10 months ago) |
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Its good for the price but lacks the 100x oil immersion objective. You could do 90% of the important stuff with it though.
Maybe this one?
http://store.amscope.com/m500.html
Or one of the inexpensive binocular ones.
The oil immersion objective is good for measuring spores and looking at the ornamentation on spores, everything else is done at lower power.
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