M42 & Lovejoy

At last the sky was reasonably clear to try out my new toy. In fact the Astro-Physics 127mm f/8 refractor is not exactly new, as it was manufactured in 1989, so I was even more curious as how it would perform.

The Super Polaris mount is definitely overwhelmed with the weight of the big, long refractor, but on a windstill evening it works tolerably well. As this was basically a test, and I didn’t want to make matters even more complicated, I didn’t use any autoguiding, and therefore limited the individual exposure times to 30s. I had to throw away about half of the epxosures due to tracking errors, but 14 exposures looked good enough to use. Transparency was pretty bad, a slight haze due to the freezing cold air and smoke from wood-powered heating combined with the light pollution of the rhine valley made the sky very bright. In the color version, the sky looks quite murky, I like the black and white rendition better:

 

14x30s Nikon D7000 ISO 1600, Astro-Physics 127mm f/8

M42, 14x30s Nikon D7000 ISO 1600, Astro-Physics 127mm f/8

Read More →

The Moon 2015-02-06

With temperatures below freezing and a strong cold wind biting into the flesh of my hands I retreated to the warm inside of the house after only a few minutes, this is a stack of 6 shots using Autostakkert.

autostakkert_50perc_stack_1600px

AP 127mm f/8, Nikon D7000, ISO 1000, 1/400s

Comet C/2014 Q2 Lovejoy

Another bright Comet Lovejoy with the designation C/2014 Q2 Lovejoy is grazing our skies these days.

The comet’s path takes it north next to the constellation of Orion, making it conveniently placed for nothern hemisphere observers.

18.1.2015

Yesterday’s sky was a bit hazy as the temperature dropped quickly and humidity condensed in the air, additionally light pollution creates a bad gradient in the west of my home.

C/2014 Q2 Lovejoy and M45 - the Plejades

33x30s, 200mm, f/4, Nikon AF Nikkor 70-200 f/4, Nikon D7000, Polarie, processed in Lightroom (Clarity & Saturation), Photoshop (Levels and Curves), Deep-Sky Stacker (dark, flat, registration and stacking) and Regim (Gradient removal)

Read More →

13.1.2015 Mercury and Venus conjunction

After work I rode my bicycle towards Liechtenstein (a very small country next to Vorarlberg, the Austrian province where I live in), to catch the Mercury/Venus conjunction next to the Egelsee. As I only had my RX100 compact camera with me, the focal length was rather limited. To pass the time for the sky to darken I took some shots of the pond.

Mercury and Venus conjunction, Iridescent Clouds

On January 10th 2015 bright iridescent clouds were visible the whole day. At sunset the colors became even more intense and many people became about this rare atmospheric phenomena. Neighbours asked what those colors in the sky actually were.

At sunset I was able to take some images of the nice Venus and Mercury conjunction.

All cloud images are straight out of camera (SOOC) with no color, brightness or contrast changes. The conjunction images were slightly processed in Adobe lightroom to make the planets stand out more prominent.

How to create time lapse video using a webcam

Simple Time-Lapse

Time-lapse animations have always fascinated me. With a time-lapse you can make things visible to the human eye that are normally happening too slow. The movement of stars in the sky or the process of putting up a house are very interesting to look at when the clock has been accelerated.

Apart form creating time-lapse animations using my own pictures I also found it worthwhile to create them from web-cam images. A webcam near the place I live provides images of quite high resolution. With the little script below, I was able to create this video: Fog over Dornbirn

I found that for videos that include clouds it is ok to take a frame every 5 seconds or so. As I don’t have the time and patience to save the webcam images manually, I created this bash script which was improved by Jürgen Hofer subsequently:

# !/bin/bash
# copyright Philipp Salzgeber - www.salzgeber.at
# adapted by j! for cleaner results
# first cmd line parameter is the delay in seconds (optional, default is 60)
# script stops if there is the file 'killme' in directory (for remote stop via dropbox)

divider=${1-60}
url=http://karren.protask.at/record/current.jpg

let "pause= $divider * 90 / 100"
while [ ! -f ./killme ]; do 
 #wait for zero crossing
 secs=$(date -u +%s)
 let "mod= $secs % $divider"
 while [ $mod -ne 0 ]; do
 secs=$(date -u +%s)
 let "mod= $secs % $divider"
 done;
 # create a filename with date and time portion
 filename=$(date -u +"%Y%m%d_%H_%M_%S").jpg
 # use wget to download the current image from the webcam
 wget -nv $url -O $filename
 # wait
 sleep $pause;
done;
echo exit condition found

Read More →

Monster Sunspot AR2192

Today I had the opportunity to see and photograph the giant sunspot Active Region 2192, it already has rotated a bit away from our direction, so the probability of a massive solar storm with possible damage to space and other infrastructure is reduced.

Full disc view of sunspot AR2192

Detail of the image above:

Closeup of Sunspot AR2192

 

The images were taken with a Nikon D7000 camera using a Astro-Professional ED80 f/7 doublet refractor. A Baader solar filter ND3.8 was used for filtering the sunlight.