Thanks for the daily sun spot pix references. I've used Big Bear's for years until they had the quakes and scope modernization projects.
Probably "singing to the choir" for most of us, so for newer astronomers on the site:
For centuries refracted white light with a carbon black filter (and later through a Herschel wedge) was pretty much the way sunspot numbers were obtained. After about 1870 or so a yellow filter was used for photography on visual refractors.
No fair using K, Ca, H
a, etc.
Yeah, sunspot numbers, like everything else have been moderized and standardized... But for long term studies modern methods are normalized to the historic white light count.
Looks like not much activity was occuring during the Venus transit in '04 either.
There are a couple of faint spots near disk center. Resolution of camera (complete w/hot spot, for calibration, ho, ho.) was erroniously not set to max. available.
First shot was as Sun was just above horizon, in fog. Had Venus been a sunspot it would have been seen as an naked eye sunspot through the fog, just like the discounted reports of the Chinese back when the sun was supposed to be perfect and unblemished. Notice the faculae are more pronounced due to the "fog's enhancement" of contrast. Last shot is a way too wide angle of OTI 94mm/f7 APO w/Al.filter used that morning.
Dissertation notwithstanding about all I was jocularly saying was that we might be in the early stages of another set of very low spot count cycles.
Certainly not an original thought.
