Try increasing gamma if dark sections aren't distinguished

Try increasing gamma if dark sections aren't distinguished

Tuesday, August 25, 2020

a perseid

back in eastbluff i decided to try out my D850 on the perseids on 8/11/20.  an extremely bright meteor streaked like lighting across the sky as i set up my camera at round 10 or 11 pm...only caught one with the camera over the next 3 hours:

Perseid 8/11/2020



close up





image details:
8/11/20, eastbluff, CA
nikon D850
Sigma 15mm F/5 EX DG fisheye
30 sec, iso 200
focusing the D850 with live view zoomed in and super high iso was a joy, giving tight stars on close up (though distorted by the fisheye) compared to the D60

this contrasts with my dark sky neowise images with twice the aperture and 100x greater ISO.  the image would be solid white if i tried that under polluted skies.  

Saturday, August 22, 2020

our galaxy

the milky way has been on my to do list for a while. here's a shot from the desert:

Milky Way 7/21/2020, Sheep Hole Valley Wilderness,  Mojave Desert


my best to date, though somewhat anticlimactic as it was a 20 second afterthought while shooting comet neowise

another edge on galaxy for comparison:

NGC 3628 35 million light years away
2007

previous attempts:
Hetch Hetchy, stacked images, dark skies old out of focus DSLR
2019


wide field stack from light polluted skies
2018 webcam


first ever 2004.  the faint "smoke" coming out of the chimney is the milky way, totally by accident






image details:
sheep hole valley wilderness, mojave desert, CA
7/21/20 10:00 PM pacific
nikon D850
wide field: Sigma 15mm F2.8 EX DG fisheye
20 sec ISO 25,600

NGC 3628
4/12-17/07
los alamitos, CA
N8 GPS, F/6.3 FR @~1280mm, SX AO @~4Hz, IDAS LPR, H9C
45x20 minutes

7/7/19 
Hetch Hetchy, Yosemite National Park, California
Nikon D60
stock lens (18-55) @18 mm f/3.5
sky watcher star adventurer mount (tracking stars)
88x30 sec ISO 400
even with dark subtraction, there was significant amp glow, hence the desaturation.

8/12/18 to 4 AM 8/13/18 AM PDT (until clouded out)
Eastbluff
Southern California
ZWO ASI 290MC
stock fisheye lens with home made cardboard dew shield and kendrick dew heater
Shutter=20.0s
Gain=100 (16%)
20 second exposures continuously

2004
Canon digital rebel
stock lens

Sunday, August 16, 2020

NEOWISE C/2020 F3 from the desert

Here are my NEOWISE images from the Mojave.
First, a starlink photobomb (a/k/a) Elon plays space invaders:
comet NEOWISE C/2020 F3 animation, series of 3 second exposures 7/21/20


close up stacked image (removing star, comet, satellite and plane trails):



wider view with a bonus early perseid:

still wider (fisheye):

Thanks to OC astronomers member and renowned astrophotographer Wally Pacholka for the inspiration:
"Gents With a comet like Neowise dropping by only every 20 years or so, can I encourage folk to see and photograph it from a dark location so you can enjoy it’s true beauty. Do whatever is necessary to leave Dodge and get out of town."
his NEOWISE images are available here:

Observations/Travelogue 
taking a tip from wally, i headed out to amboy crater, in the Mojave desert 
Amboy Crater

an ideal location due to the absence of light pollution in the northwest where the comet would be setting:
after a bit of reconnoitering, i opted for a location a bit south of the crater then made a few minor adjustments for local wild life:
snake spoor
 
visually, the comet was spectacular, spanning 5 degrees of sky (10 degrees with binoculars) almost as bright as the milky way, though more focal.  

photographically, saturday night (7/18/20) was a bust.  it seemed my 10 year old nikon D 60 which was fine in light polluted skies was not up to dark skies in 100 degree heat (but it was dry heat)

A rare case where the camera is less sensitive than the eye (or cellphone):
Nikon D60 stacked and processed

cellphone:
Samsung Galaxy Note 9 single frame

having flailed with my Nikon D60 Saturday night, i went back out to the desert Tuesday night to try again, armed with a better camera (rented nikon D850) and more glass. 
 
This time at the sheep hole valley wilderness (south east of amboy) just north of eastern joshua tree.  
the sheep hole mountains on the left of the widefield are shielding the barstow (and 29 palms) light dome which i assume can be seen from much of joshua tree when looking NW:



Image details:
sheep hole valley wilderness, mojave desert, CA
7/21/20 ~9:20-11 PM pacific
nikon D850
close up AF-S NIKKOR 85mm 1:1.4G 
10x stack 3 seconds ISO 25,600!
stacked in deep sky stacker
intermediate: AF-S NIKKOR 18-55mm 1:3.5-5.6G at 18 mm
30 sec ISO 25,600
wide field: Sigma 15mm F2.8 EX DG fisheye
20 sec ISO 25,600
lens distortion correction in photoshop

spent too much time stacking images which wound up worse than single shot except for the close up.  
super high ISO, blew out the star colors, but stacking with lower ISO images didn't work out for me.  
NEOWISE 7/21/20 5 sec ISO 6400, better star color and green at comet core