Try increasing gamma if dark sections aren't distinguished

Try increasing gamma if dark sections aren't distinguished

Sunday, October 26, 2014

solar selfie from 10/23/14 eclipse

why call it a silhouette when i can be trendy?
if you look around while the sun is partially eclipsed, you may notice strange things in the shadows: a blurring of the sharp line between light and dark, strange shapes in light.  leaves in the trees may create a pinhole camera effect giving projections of the eclipsed sun on the ground.
i couldn't find an example in the immediate area so i made one myself ;)

I know, you're thinking that's just my first web space casting a shadow.  Here's a more dramatic example i encountered indoors created by holes in the blinds:

Thursday, October 23, 2014

eclipse preview and a monster spot

as usual, the sun has upstaged the moon, producing the largest sunspot folks have seen in years at the same time as the partial solar eclipse.  it's so big folks are simply referring to it as the monster.  larger than jupiter and easily visible without magnification (eclipse glasses only).
here's a section of it:

and here's the full disk in hydrogen alpha mid way through the partial eclipse:

more to follow...

Sunday, October 19, 2014

solar surface animation, eclipse alert 10/23/14

OK first up
there will be a solar eclipse visible from the US on thursday 10/23/14.
needless to say, as it's only a partial eclipse, the sun will still be blindingly bright.
protective eye-wear or projection is a must for viewing.

not much happened in my full disk Ha animations.
close-ups of prominences however gave interesting movements.
so here are some close ups of the disk surface.
not quite as dramatic as a prominence lifting off, but still interesting.
first, here's the full field (click on image for full size):

high contrast grey-scale

here's a circular filament around an active region:

here are what look like classic magnetic field lines from one sun spot to another:

a filament arching off the surface:

eruptions around a sun spot, which, i guess is why they're called "active regions":

imaging details:
7/5/14 newport beach, ca
DMK 51, 2.5x Powermate, Lunt 60 PT B1200
2 hours of imaging at ~12 fps every other minute
best 300 frames every minute
7.8 ms exposure
the images were spoiled by dust on the sensor
finally salvaged them by creating artificial flats
though you can still see some faint shadows of dust spots in the animations
(right side of last)

Monday, October 6, 2014

Saturn 2014

forgot to send out this year's best shot:
getting some nice color in the bands
a hint of the north polar cloud, but no hexagon
can see Cassini's division and the maybe Encke minimum

the images are taken by using a video camera, stacking thousands of short long exposures
allowing processing software to select the images least distorted by seeing
stacking thousands of images in this way gives a much more sharp image

in theory one can upsample the video by 2x to get better magnification
so i decided to do a test, comparing and upsampled image
with an image using a 2.5x barlow to give more magnification
but requiring longer exposure.

which will be better?
larger magnification with longer exposure
or shorter exposure eliminating seeing effects?

2.5x barlow:

upsampled 2x:

compare the Encke minimum and colored bands
close, but i think the barlow wins
though the seeing wasn't really sufficient for either