Try increasing gamma if dark sections aren't distinguished

Try increasing gamma if dark sections aren't distinguished

Thursday, October 19, 2023

Annular eclipse at the Albuquerque Balloon Fiesta 10/14/23 part II: Ring of Fire

a few clouds and a lazy contrail on the horizon made for an interesting sunrise, but didn't impact the rest of the eclipse (click on image for full size):

sunrise balloon fiesta park
abluquerque, NM
8/14/23 06:37:27


first contact:
first contact (upper right)
09:13:22
partial phase:
09:30:12
bye sunspots:
10:14:12

The announcer called out annularity and all the grounded burners in the field fired up.  note the annular reflections below the sun:
annularity, balloon fiesta park
abluquerque, NM
8/14/23 10:36:11
RING OF FIRE: there was a lot of talk about a "ring of fire" eclipse, but no images really show it.  here's my attempt, I digitally overexposed this image to simulate an unfiltered image of the sun (which would melt my camera sensor) to portray an actual "ring of fire"
ring of fire

here's a more conventional portrayal.  bullseye with the camera--my location was dead center eclipse path:
annular solar eclipse
balloon fiesta park
abluquerque, NM
10/14/23 ~10:36:32
cellphone:
filtered

broken ring:
image rotated horns up
10:39:09

Next up: animation and montage

Imaging details:
10/14/23
Albuquerque, NM

nikon D850
AF-S NIKKOR 300mm f/4E PF ED VR
Baader solar film, Fotga IR/UV cut filter
iso 100 1/1250-1/2000 sec exposure
Vello Shutterboss Version II Timer Remote Switch
skywatcher star adventurer tracking mount

Samsung galaxy S22 ultra
for field shot and filtered cellphone image
eclipse image shot with solar filter at 30x

processed in photoshop

    Arriving early for the pre-dawn activities allowed me to dial in my polar alignment for my tracking mount, only adjusted my alignment once.
    While i tested my exposures repeatedly at home, to be sure my images were not clipped, as the sun rose higher in the thin albuequerque air the face of the sun became slightly clipped, losing the subtle surface granulation. fortunately, i caught it relatively early and decreased the exposures from 1/1250 s to 1/2000.  if you look closely at the partial phase above, you'll note a lack of subtle granulation across the bright face of the disk (09:30:12), which can be seen in the subsequent image (10:14:12)
    The nikon D850 has a built in intervalometer which is great for meteor showers and overnight sequences, but awkward to adjust on the fly.  there is software to connect a smart phone via bluetooth or wifi, but it disconnects every time you switch apps and takes >30sec to reconnect.  less than ideal for the eclipse experience unless you use a dedicated tablet.  
    I chose to used the vello shutterboss version II timer remote switch, a wired solution that can trigger the shutter manually without shaking the camera and be used as an intervalometer that can be rapidly adjusted.  i chose 4 minute intervals for the partial phases and 1 second intervals for annularity.  for the 3rd contact i held the manual trigger down with the camera set for continuous low speed shots, having determined 4 fps is the fastest my camera will write full frame raw files (8288x5520 ~53 meg) to the chip.  it can do bursts much faster but only for a few seconds.  
    I found these an excellent focus aid -o-o-


    In terms of processing, the auto color balance with the IR filter and baader film was all over the place.  By trial and error, I came up with something close to white by setting the temperature to 7100 and tint to -40 for raw conversion.  this still gave a slightly non-uniform color white in the center and slightly red red at the edges which was acceptable, though I desaturated the white images above.  not sure why the color was not uniform.  either the camera sensor is non-linear or the solar color is non-uniform.  here's the "natural color"
10:14:12

    for images with a substantial amount of the central solar disk showing, i applied a high pass filter at 1.5 radius soft light, then again at 2.5 radius hard light 50% blend (excluding the solar and lunar edges). this brought out the sunspots and surface granulation.  color images colorized at 25 hue, 100% saturation, -20 lightness

Sunday, October 15, 2023

Annular eclipse at the Albuquerque Balloon Fiesta 10/14/23 part I

In planning the eclipse viewing site, I looked for 2 things: proximity to a major airport and a good probability of clear skies (see references below).  I considered Albuquerque (so fun to spell) and learned the last weekend of the Balloon Fiesta, the  largest hot air balloon event in the world, coincided with eclipse day.  Boasting the most photographed event in the world, the fiesta hosts over 600 balloon teams. The overwhelming synchronicity made this the city of choice.  

Note: some browsers require you to click on videos twice to play, click on images for full resolution, lower right icon will give video in full resolution.  

The event started with a drone lightshow:


propane burners fueled the lighter-than-air crafts and lit up the fiesta:


next came dawn patrol: a small group of balloons launch pre-dawn in order to test the winds at various altitudes for the rest of the pilots.  




dawn patrol meets orion

Next, rows and rows of balloons lined up for the mass ascension:
closest row


next row getting ready


closest balloon setting up




The "mass ascension" started shortly after sunrise.  

Was not expecting much from the star spangled banner.  The flyby pilots timed it perfectly, complemented by all the ground burners going off at once. Had I realized, I would have captured the whole thing.  

up up and away:



Balloon Fiesta, Albuquerque, NM 10/14/23

What do you  get when you cross a balloon fiesta and solar eclipse?
A Balloonar Eclipse! 😂




impending balloonar occultation of venus

special balloons:






the eyes on the ground belong to yoda
who's apparently lost his flying skills

eclipse epiphenomena:


semicircular shadows between fingers
patented ring/annular eclipse pose
semicircular shadows between leaves


Finally all the balloons have launched from the field as spectators watch the moon's shadow cross the sun.  Take a close look at the diffraction pattern around the sun in this image:
Zia symbol heralds annular solar eclipse in New Mexico
the land of enchantment
New Mexico State Flag

Here's a cell phone shot of the partial eclipse:
Partial solar eclipse
10/14/23 9:35 AM Local
Albuquerque, NM

Next up annularity and long focal length DSLR images

Imaging details:
10/14/23
Albuquerque, NM
Samsung galaxy S22 ultra
partial eclipse image shot with solar filter at 100x, then reduced to 10x
Arriving early for the pre-dawn activities allowed me to dial in my polar alignment for my tracking mount, only adjusted my alignment once.


References:
Xavier M. Jubier's website integrates with google maps superimposing the eclipse path and details for any point selected along the path.  

https://eclipsophile.com/ gives historical weather for cities along the path


Sunday, October 1, 2023

pitfalls and perils of solar imaging: testing for upcoming solar eclipses

testing my solar imaging:
sun 
9/23/23
baader film filter
single exposure 1/1,000 sec ISO 100, 300 mm f/4

Close up of the sun this summer, while trying to image venus during inferior conjunction with the sun:
sunspot 8/13/2023 20:05 UTC

I failed to image venus during inferior conjunction with the sun.  The conditions were frustrating: very bright, hot, poor seeing, and windy.  I was able to see it visually, but had difficulty focusing the camera, so slewed to the sun with a solar filter to focus on an obvious target.  while focusing, i noted a bright spot on the ground...the lens cap had blown off the finder scope objective leading to this unplanned modification of the eyepiece lens cap.  At that point I abandoned the attempt.  
Finder scope:
hole burned in finder scope lens cap





boring test stuff:
i cannot focus manually :(
best manual:


typical auto:
autofocus with light clouds
1/1000s

IR/UV block filter off center 4x exposure:
1/250 sec

125x exposure:
1/8 sec

125x exposure no IR/UV block filter:
1/8 sec

1000x exposure no filter, f/4:
1 sec

1000x exposure no filter f/5.6
1 sec


imaging details:
full disk testing 9/30/23
nikon D850
AF-S NIKKOR 300mm f/4E PF ED VR
Baader solar film, Fotga IR/UV cut filter
iso 100

sunspot
camera ZWO ASI 290MM with 850 nm IR pass filter, baader solar film
celestron 11" Edge HD
mediocre seeing
8/13/23

East Bluff, CA

Wednesday, September 27, 2023

Lunar Rays

Lunar rays, streaks of debris radiating out from craters, are among the few structures better seen during a full moon than a partial phase

Technically, there are 2 other types of lunar rays:

1. rays of light shining through a break in a lunar mountain range/crater during lunar sunrise.  these esoteric phenomena are challenges for advanced lunar observers and difficult to catch. 

2. a bunch of dudes named Ray something...(sorry)

The massive ray structure around tycho (lower right below) is easily seen though binoculars:

massive lunar rays surrounding tycho (right below center)
copernicus and kepler (middle, below center) 
full moon 11/27/12

The butterfly pattern around crater proclus suggests a low angle impact:

lunar rays around crater proclus
8/29/2023 06:42 UTC
(click for full size)
top full moon picture above

Menelaus and rays
8/29/23 06:59 UTC
(click for full size)
upper mid left full moon image

craters messier a and b are thought to have formed by a single  impacting body coming in at a very low angle:

Messier A and B
8/29/23 06:48 UTC
upper right full moon image

Here's a mosaic of craters copernicus and kepler and surrounding rays.  (left the rough edges for the mosaic feel).  click for a moon walk:  

Copernicus and Kepler
9 panel mosaic
8/29/23 07:05-07:17 UTC
(click for massive size)

Imaging details:

the full moon is usually the bane of astrophotographers
in accordance with murphy's law
it took me months to capture images during a full moon when i actually wanted to due to cloud cover.  

camera ZWO ASI 290MM with 850 nm IR pass filter
celestron 11" Edge HD
mediocre seeing
8/29/23 06:41-07:17 UTC
lunar waxing gibbous 12.5 days old

East Bluff, CA
captured in fire capture
stacked in autostakkert
light wavelets in registax
mosaic in maxim (tried and true worked amazingly well)
photoshop
topaz denoise worked wonders for slight noise reduction and dramatic detail recovery
(first sharpening has ever worked well for me in topaz)
low light
remove noise 1
enhance sharpness 63

full disk
11/27/12
FS 102, SX H9 (probably)

Saturday, September 23, 2023

saturn opposition 2023

managed to have clear skies, decent seeing and the next morning off enabling me to catch saturn at the exact time of opposition and within minutes of local transit:

Saturn 8/27/23 08:16 UTC
Eastbluff, CA

here's a wider view with the moons.  

Saturn and Moons
8/27/23 07:54 UTC
composite image
none of the bright moons were blocked by saturn's glare, though several were out of the field.  had i known i would have captured a wider mosaic to catch them all.  

Dew soaked imaging rig:

Imaging details:
camera ZWO ASI 290MC with IR block
ZWO ADC
celestron 11" Edge HD, no barlow
East Bluff, CA

close up:
16 x 90 second captures, 1 x 422 sec
gain 351, exposure 1.988- 8.904ms, 77%-29% histogram, 100-200 fps

wide view:
composite
60 sec gain 351, exposure 100ms, 100% histogram, 10fps
60 sec gain 351, exposure 9.497ms, 89% histogram, 24 fps

captured with firecapture
stacked in autostakkert (upsampled 1.5x)
combined in winjupos 
processed in registax and photoshop

notes:
image snapped to focus on titan
meridian flip in past created tube currents in perfectly calm scope
cooled down aiming at planned imaging location in sky
fire capture ADC adjustment worked really well (custom button assigned for easy access)
blow drier much better than dew heater
dramatic increase in histogram after use mid capture

best images initial or after blow drier
shorter exposure better for 30% histogram 
(80% histogram exposure limits capture rate)
longer imaging time better
7 minute capture slightly worse after winjupos derotation
(required debayering of long AVI in PIPP)
but still better than 90 second.  
should increase to 120 for saturn
needed to set LD to .5 in winjupos
 
appendix:
3x no fan
0757
FPS (avg.)=39
Shutter=8.904ms
Gain=351 (58%)
Histogramm=77%

0758 
FPS (avg.)=112
Shutter=8.904ms
Gain=351 (58%)
Histogramm=74%

0800
FPS (avg.)=106
Shutter=8.904ms
Gain=351 (58%)
Histogramm=71%

3x fan on (no clear difference)
0802
FPS (avg.)=109
Shutter=8.904ms
Gain=351 (58%)
Histogramm=69%

0804 
FPS (avg.)=106
Shutter=8.904ms
Gain=351 (58%)
Histogramm=72%

0806
FPS (avg.)=108
Shutter=8.904ms
Gain=351 (58%)
Histogramm=72%

3x short exposure/low histo (no clear difference)
0808 
FPS (avg.)=199
Shutter=4.754ms
Gain=351 (58%)
Histogramm=42%

0810
FPS (avg.)=194
Shutter=4.754ms
Gain=351 (58%)
Histogramm=38%

0812
FPS (avg.)=194
Shutter=4.754ms
Gain=351 (58%)
Histogramm=36%

3x saa after blow drier (clearly better)
0821
FPS (avg.)=192
Shutter=4.754ms
Gain=351 (58%)
Histogramm=72%

0824
FPS (avg.)=192
Shutter=4.754ms
Gain=351 (58%)
Histogramm=71%

0826
FPS (avg.)=171
Shutter=4.754ms
Gain=351 (58%)
Histogramm=70%

3x shorter exposure.low histo
0828
FPS (avg.)=207
Shutter=1.988ms
Gain=351 (58%)
Histogramm=31%

0829
FPS (avg.)=217
Shutter=1.988ms
Gain=351 (58%)
Histogramm=32%

0831
FPS (avg.)=218
Shutter=1.988ms
Gain=351 (58%)
Histogramm=33%

0833 
FPS (avg.)=215
Shutter=1.988ms
Gain=351 (58%)
Histogramm=30%

0843 long run
FPS (avg.)=209
Shutter=1.988ms
Gain=351 (58%)
Histogramm=29%