Try increasing gamma if dark sections aren't distinguished

Try increasing gamma if dark sections aren't distinguished

Sunday, February 4, 2018

super blue blood moon

here's the rising full moon on the evening of 1/30/18 followed by the setting super blue blood moon from the next morning (click on images for full size):

darker version with a bit more detail:

The full moon above is sharper than the eclipsed moon for several reasons:
1. the eclipsed moon was lower in the sky, therefore subject to more atmospheric turbulence
2. the faint eclipsed moon required longer exposure (500x), also increasing the effect of atmospheric turbulence.  

shot this one in lazy mode.  my garage faces west, so i set up my imaging rig the night before, taking a quick image of the full moon to make sure everything was working.  then moved the equipment into the garage facing west, closed the door and went to bed.  
got up and 5 AM, opened the door to my "observatory" and voila super blue blood moon over my neighbors house:

I'd checked the framing with the setting moon the week before.  this image took a fair amount of work in photoshop as the street lights gave the house a strange green tint. there was also star trailing evident over only 20 seconds (seen below), so i pasted the telescopic version over the moon image in the wide field DSLR image.  


imaging details:
close up:
ZWO ASI120MC, Takahashi FS-60C at native F/5.9, 355 mm.
skywatcher star adventurer tracking mount  
full moon .325 ms exposure 12 seconds captured at ~17 fps
eclipsed moon 152.6 ms exposure 68 second capture at 6 fps
13:24 UTS
wide field:
Nikon D-60, AF-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR, f/5.6 55 mm 20" iso 400
1/31/2018

Eastbluff, CA






Sunday, January 28, 2018

Copernicus infra red

Here's a close up shot of copernicus, one of the most photogenic craters on the moon with its terraced walls and central peaks: 
Copernicus 9/10/16 infra red filter
click for moon-walk size


it's easily visible to the naked eye here:
7/8/17 IR/UV block filter


Interestingly, the crater was named by a jesuit at a time when church doctrine opposed the heliocentric model.  The crafty jesuit justified naming such a prominent crater after the father of the heliocentric model by noting that the astronomer was placed in oceanus procellarum, the "ocean of storms". wikipedia link with more information about the crater

The image of the crater was taken with an infra red filter and a telescope that is "mostly" a reflector (mirrors).  it was a test shot which proved that the IR filter was sharper than standard visible filters.  more on that in this post on jupiter.  
Interestingly, the full disk image was taken with a filter that blocks infra red.  why? it was taken with a refractor.  refractors use lenses to bend light.  since infrared light bends less than visible light (the same phenomenon that made it desirable in the previous image), it doesn't focus well in refractors, creating a blurry image.  


Technical notes:
Copernicus: celestron nexstar 8 GPS (8" SCT on a wedge)
ZWO ASI120MM-S
captures with firecapture @ ~58 fps
stacked in autostakkert, Drizzle 3x, then reduced to 1.5x, sharpened in registax 6
9/10/2016
Full disk: DMK 51 and the tiny tak, Takahashi FS-60C, 60 mm aperture at f/4.2 with a reducer.  The field of view is approximately 96x72 arc minutes.  1 minute video capture at approximately 12 fps, aligned in autostakkert, wavelets in registax.
7/8/2017
Eastbluff, CA

Sunday, January 14, 2018

Sunday Sundogs and a pillar

saw a pair of Sundogs while running in the back bay today.  pointed them out to everyone i passed.  most thought i was crazy, but one couple shouted a "thank you" after they found it.



Sundogs 1/14/18



Sundogs are caused by light refracting off hexagonal ice crystals.  if they are random a halo is formed, if they are horizontal, two spots are seen on either side.  Here's a nice explanation.  

Here's a phenomenal example of a double solar halo with sunddogs taken from a ski slope in sweden:

speaking of solar images, here's an Ha image of a "straight pillar"--a form of solar prominence:


Image details:
sundogs:
cellphone Droid turbo
Eastbluff, CA 1/14/18
Ha:
Lunt 60 PT 
ASI 290 MM camera
20 second video 183 fps
Shutter=5.0 ms
Eastbluff, CA 1/4/18