WAITING FOR THE SHADOW      ASTROPHOTOGRAPHY by Joseph Cali

"Scorpius & Rho"

Faced with a beautiful dark sky near Yass but feeling very tired from a poor nights sleep the night before what do you do?  Not wanting to set up a tracking mount, I decided to try the Pentax Astrotrace function to take some shots from a fixed tripod.  Astrotrace uses the camera GPS to tell the camera where it is pointing and where it is geographically located.  The camera processor then uses small movements of the image stabilizer, to shift the sensor to minimize the effects of the Earths rotation visible in the sky.  No system can rotate the image around the celestial poles.  It simply minimizes movement across the whole frame.  In the above image, you can see some movement at the lower right corner of the frame but the rest of the image is not bad. The lens is a 1970's built Pentax M 50mm f1.7 that gives pretty sharp images from f2.8 down. 

Camera:      Pentax K1
Lens:           Pentax M 50mm f1.7
ISO:            3200  f5.6
Exposure:   4 x 2 min exposures median stacked in Photoshop

Andromeda Galaxy
Pentax K1 ISO800, 13x 2mins, Pentax EDIF300mm f4 @f4.5

Large Magellanic Cloud
Pentax K1, ISO 2500,  Pentax EDIF 300mm f4, 17 x 2 mins @ f4.5

47 Tucana ( NGC 104)
Pentax K1, 14 x 2 min subs, ISO3200 x 4, ISO1600 x 2, ISO400 x 8
Pentax EDIF 300mm f4

Pentax K1 / ISO 3200 /  Rokinon 135mm f2 / 11 x 45s exposures stacked in Adobe Photoshop

Orion was getting down and dirty as it was setting. I captured 8 frames, 2 mins each to record Barnard's Loop.
I wanted to do this when it was high in the sky, earlier in the season, but beggars can't be choosers.

Check out Betelgeuse, the orange star upper right. It's usually as bright as Rigel, the bright blue star lower left.
Most of this summer, it has been closer to the brightness of Bellatrix (blue star lower right) and noticeably fainter
than usual to the naked eye.

Though opportunities to observe have been sparse, it's been fascinating to look up and see an "old friend" so faint
and frail. It is recovering from it's recent "fainting" spell and returning towards normal luminosity.

Antares, M4 and Rho Ophiuchi 
Pentax K1 / ISO 1600 /  Rokinon 135mm f2.8 / 10 x 120s exposures stacked in Adobe Photoshop



Zeta Scorpii
Pentax K1 / ISO 1600 /  Rokinon 135mm f2.8 / 10 x 120s exposures stacked in Adobe Photoshop