|User’s votes are weighted by their contribution to the site (log10 contribution). In addition, the user who created the observation gets an extra vote.|
|I’d Call It That||3.0||0.00||0|
sum(score * weight) /
(total weight + 1)
Interesting … you’re making me more UV conscious … my little flashlight has two UV wavelengths, but it doesn’t even say which is which. The overall effect is that one is much brighter than the other and elicits better responses, so the wavelength of the emitter might be critical.
…are suspicious. I find a few to be very reliable and useful but never mentioned in the literature, or downright contradicted. I’m pretty sure I’ve seen James Lendemer say that usnic acid is UV-, yet it always gives a dull yellow for me and I find it extraordinarily useful. All orange things glow a bit in UV for me, including all Chrysothrix, Candelaria, Candelariella, Caloplaca, Letharia, Vulpicida, etc. Secalonic-A gives a nice weak yellow in UV for me (that’s the weak pigment in Physconia enteroxantha and the other related species), very hard to see with the naked eye, and even the spot tests are never very confidence-inspiring, but the UV test works great. Never mentioned anywhere.
But I can never see the UV+ white of perlatolic or alectoronic acids.
I’m just totally confused at this point. It’s got to have something to do with wavelength. What else could it be?
Using K would have been (ahem) a good test: Caloplaca is K+ red-purple immediately (anthraquinones), while Candelina submexicana is K-. Also, Candelina submexicana is UV+ “dull, very dark orange (calycin)” (Brodo et al., 2001, p.210). Is Caloplaca ever UV+? A quick scan of Brodo did not turn up any mention of UV in the Caloplaca section.
Created: 2011-06-20 01:11:12 BST (+0100)
Last modified: 2011-06-20 01:18:55 BST (+0100)
Viewed: 46 times, last viewed: 2016-10-26 20:24:46 BST (+0100)