Beiträge von Steve_mt

  • Cortinarius sp. ? under Cistus (and Thymus) from calcareous soil


    Dear Uwe,


    I heard nothing from Unite, so giving them the fair chance to reply, and they did not, I am OK to move on with you. This is the first time to send material for DNA sequencing, hence where should I send the sample to you UWE? - I send you PM as requested

  • Cortinarius sp. ? under Cistus (and Thymus) from calcareous soil


    Dear Uwe,


    I herad nothing from Unite, so giving them the fair chance to reply, and they did not, I am OK to move on with you. This is the first time to send material for DNA sequencing, hence where should I send the sample to you UWE? - I send you PM as requested

  • Stated magnification versus real magnification

    Would be nice if someone can test the same procedure and calibrate the measurements with oil and without oil for the x100 objective and see if there are same results. Because if one measures spores under oil immersion and applies a 1:1 scale, there might be some 15% error in the measurements!!!! --- or is it just me here with this anomaly ?!?!

  • Stated magnification versus real magnification

    this morning tried the calibration without oil and I got 96-97 units for 100um (everything same setup but no oil on stage). The focusing and sharpness was quite good actually! That makes 100/97 = 1:1.04 which is a good match.


    Replies:

    I second Peters opinion that the problem is the measuring scale in the eye piece. >> Same eyepiece reticule for all objectives (which gives expected values)


    You should have the same unusual multiplication factors also in the other magnifications, means 1:4,25 with the 40x objective (instead of 1:2,5) and 1:17 with the 10x objective (instead of 1:10) - correct? >>> For the other 'air' objectivesI get a close value to the expected magnification.


    Your eyepieces are 10x?

    Yes E-Pl 10

    Or you can buy a "real microscope" from Olympus right away.:saint:

    You need real money too!

  • ​ Diderma sp. (hemisphaericum?) on leaves of Juglans and other deciduous trees

    hilmgridd , dont worry about the English, what's important is that we communicate .... (although I couldn't get the joke about the egg lol!). I attach two more photos of this Diderma species from a previous collection which was more typical (well-developed stipe) for you to admire. Yes it is a lovely slime mold looking like tiny satellite radar discs.

    Agreed eith LG Ulla, the species is not specific to Juglans (I found it earlier on carob leaves and Rubus ulmifolius decaying stalks) but I think it requires a lot of humidity and likely a thick layer of leaf detritus.

  • Stated magnification versus real magnification

    Thanks - but have I posted in the microscopy section already? I start thinking what happens without oil immersion ...and also if users here calibrate the magnification (for measuring) compensated for oil immersion! ! !

  • Stated magnification versus real magnification

    Hi there,


    I don't really believe that the lens delivers such a clear change in the image scale.

    - Was it really readable 1: 1 before?

    No, always 1:1.17 (oil mount)


    - Is the measuring eyepiece the same as before?

    Eyepiece original of microscope (Zeiss Axioscop 20) but reticule different.


    - Is the measuring scale in the eyepiece the same? (There are so many different scales)

    yes


    - Has the graticule slipped in the measuring eyepiece?

    No


    - Is the microscope micrometer inserted the right way round?

    \yes, if not the numbers of the micrometer will be inverted and I would know


    The easiest way is to screw in the two 100 lenses side by side and compare them directly.



    Peter, maybe you are misinformed, but the lens always gave this 1:1.17, that is, it was not like it was giving 1:1 and now all of a sudden 1.1.17. If I remember the previous x100 objective did the same.


    regards

    Peter



    I wonder if you guys have your x100 objective giving 1:1 or 1:>1? when using oil (that is you put a drop of oil on stage micrometer)

  • Stated magnification versus real magnification


    Hi Andreas, I bought it from ebay and there is one like it here:

    Zeiss Plan-NEOFLUAR 100x/1.30 Oil Objective


    I was told infinity objectives made by Zeiss should work on Zeiss microscopes so I had a budget and this objective looked really good. However I am a bit disappointed with the resolution, and often the lens has to touch the cover slip to have focus. I don't know if, If it does work well for transmitted light application.


    Maybe u r right re used ONLY for fluorescent microscopes, but websites selling the exact obj are saying that it could be used both for light and florescent applications ! As far as I know, such a specific lens should be colour coded . where black it means for transmitted light





    Zeiss Plan-NEOFLUAR 100x/1.30 Oil Objective



    I also have this objective : Zeiss Plan Neofluar 100x/1.30 Oil Pol Microscope Objective Lens 440483 for sale online | eBay

  • Stated magnification versus real magnification

  • Stated magnification versus real magnification

    But then the 630x objective at same conditions (except not oil) does not suffer from any discrepancy.

  • Welche Pilze sind das?

    nobi_†: So true, but then a genus name is already very good for newbies .


    @ Fungi : Agree with the above, there are quite some Psathyrellaceae in the bunch. For better expectations, ideally you post species pre post and take several pics from different angles including scent. In several other fora or social media you want be helped from such a photo.

  • ​ Diderma sp. (hemisphaericum?) on leaves of Juglans and other deciduous trees

    I found an interesting myxomycete, rather abundant on fallen leaves of Juglans regia and few other exotic trees. Initially, they looked like small flour sacks or pouches, quite large (2mm perhaps), and quite cute. On further development, there were some slimy droplets oozing (maybe damaged during transport) and finally, they solidified into irregular flattened disks and dehisced in a particular way. Must be a Diderma sp. and maybe globosum or more likely D. hemisphaericum. However, the latter should be distinctly stalked! On careful examination, the myxocarps were subsessile (neither distinctly stipitate nor sessile). For me, it looks more like hemisphaericum unless there are other species that I have not considered. I am aware micro is needed but for this I might be lucky to decrease the workload!

  • Congo Red

    I was about to write that 3g/100mL = 3% is too concentrated (usually literature suggests 1%). I opt for 0.8% in my preparation and see if it works well.


    And just for fun, I found a thesis on colours of Congo Red written in 1927 by Robert S. Radcliffe.


    RICE1273.pdf?sequence=1&isAllowed=y


    Thanks Andreas and Andreas

  • Congo Red

    Thank you Andreas, what % is the Ammonia, around 10% maybe?


    I am preparing new solution from the powder now, that Congo Red is strange.


    I take the long cut, I dissect and put the section in congo red. Leave for a minute or so, then I absorb the extra stain with a cotton bud or kitchen roll strips and add plenty of 3%KOH and wash the dissection in it (sometimes leave it to stand for another minute if the tissue is robust/hard). Then I pick the washed section and place it in a drop of KOH+Glycerol mixture, sometimes a dissect further in smaller pieces and space them out. I place the cover slip over, press with a rubber over tissue paper and ready to go. The glycerol mixture prevents the slide from drying.


    Cheers :S