Smokedaddy wrote:Charles,
Very nice. I've noticed on a few that I've tried to image, even some diatoms that they appear to have a hole in them and you can see through them into the inside. Is that some sort of artifact in the processing or simply a lighting illusion ... kind of like the circled area below.
Would you mind telling me (or someone else can jump in) and tell me what auto-fluorescence means and UV (365nm) excitation? I haven't plugged in or hooked up my fluorescence components yet.
No hole there , just the way the surface is angled.
"Autofluorescence" is a
natural emission of light by a subject that has been illuminated with certain wavelengths of light. The majority of fluorescence microscopy is done adding fluorophores (chemical compounds that fluoresce) to the material to be studied.
The light that illuminates the subject is called the "excitation" light. If a subject auto-fluoresces, it will then give off a different, and longer wavelength.This emitted light can be quite dim, so it is important to block any other light that might prevent you from seeing it. This is accomplished by using filters that will block all of the wavelength of the excitation light. Your microscope fluorescence cubes will have such filters. There is a large variety of combinations possible (fluorchromes, excitation wavelengths, filters), and they are typically chosen to work well with certain subjects.
For natural autofluorescence, UV light of about 365nm is generally pretty good at causing many subjects to fluoresce. Also good is blue light of around 450nm.
