Pitufo,
Magnificent images! Bravo!
Question: Are the rainbow colors of the spheres "inherent" and persist in varied lighting? If so, likely due to pigment? Or are they the result of "speckle" from a coherent or semi-coherent light source bouncing off a semi-mirror-like structure? This question may be foreign to someone who concentrates on living things, but such speckle is common when photographing metals, such as coins, and optically-similar subjects.
A very interesting test of the above would involve your taking pictures of these structures with maximally-diffused light. If you could do this, we could compare coloring and get a sense of how much the rainbow coloration depends on lighting coherency. This said, I'm all too well aware that your subjects change very rapidly--so this comparison may be impossible.
Still, can you provide any insights?
--Chris
Myxomycetes
Moderators: rjlittlefield, ChrisR, Chris S., Pau
-
rjlittlefield
- Site Admin
- Posts: 23626
- Joined: Tue Aug 01, 2006 8:34 am
- Location: Richland, Washington State, USA
- Contact:
Thanks Chris and Rik,
Yes, I think the rainbow colours do persist in varied lighting and are due to thin-film interference of a membrane as suggested by Rik. Irridescence is commonly found mainly in this particular genus.
These shots were taken with maximally-diffused light as I have found that this is the best way to capture them. I have been using a simple A4 paper diffuser with 2 x 10W Tronds (thanks Beatsy for that idea http://www.photomacrography.net/forum/v ... hp?t=31825). More concentrated sources of light don't seem to give good results.
John
Yes, I think the rainbow colours do persist in varied lighting and are due to thin-film interference of a membrane as suggested by Rik. Irridescence is commonly found mainly in this particular genus.
These shots were taken with maximally-diffused light as I have found that this is the best way to capture them. I have been using a simple A4 paper diffuser with 2 x 10W Tronds (thanks Beatsy for that idea http://www.photomacrography.net/forum/v ... hp?t=31825). More concentrated sources of light don't seem to give good results.
They do change rapidly but, once mature, these structures are actually quite stable and if dried and stored free of bugs and fungi can last for years.This said, I'm all too well aware that your subjects change very rapidly--so this comparison may be impossible.
John
Cribraria violacea
Cribraria violacea on willow bark culture in a humid chamber. The spores are around 8um in diameter.
