I've copied below a comment and response from http://www.ispot.org.uk/node/369824 in the hope that others have trodden this road before us and can offer some guidance.
Thanks in advance.
20 September 2013 - 7:11am — marksteer
Great to see some microscopy! Please details - magnification, any special preparation of spore sample? I only have USB microscope to x200 mag so can't get to spore level. Have confirmed id as Paxillus involutus, species I see quite often.
20 September 2013 - 7:53am — Thistle
I wish I could give you some worthwhile information but I simply bought a cheap USB microscope from eBay with no instruction manual. It has 3 objectives: x4, x10 and x40.
I lay the fungus on a blank slide for a while until I can see that some spores have dropped then shove it under the x40 lens. It doesn't give me any detail of the spore surface and the software I have (ULead) doesn't allow me to calibrate the microscope to determine sizes. It does give some indication of the spore shape and, after you've done a few, an idea of relative spore size.
(Perhaps if we re-started this discussion on one of the forums we might both learn something?)
Thanks your comments. I'm surprised you are able to get spore photos at x40. I've not experimented much with my USB but it goes to x 200 and I couldn't see individual spores. I'll have to try again! Mine was from Aldi!
Spores for P. involutus are around 10microns - pretty small!!
I'll let you know via this Forum how things go.
Glad to see iSpot is a bit faster again - it's been pretty abysmal recently and I stopped posting Observations and comments will try again and see how things go!
The more I know the more I realise I don't know
You might be interested in the following link:
Not sure if anything near to you but if so maybe some experts around who could advise you.
I have an event not far from me which i will be going to. It will be run by a very good expert on fungi who has set up a lab for fungi and I hope to get some tips from him on microscopy.