In the first night I used my 80mm f/7 ED Apo for unguided 30s sub-exposures, in the second night, the 127mm f/8 Apo with 120s guided exposures…
Tag Archives: Astro-Physics
Lunar telescope comparison 80mm, 127mm, 200mm
Last night I photographed the same lunar regions through 3 different telescopes:
- Astro-Professional 80mm ED f/7
- Astro-Physics 127mm f/8 refractor
- GSO 200mm f/5 Newtonian
Andromeda Galaxy – M31
In Autumn the Andromeda galaxy is conveniently placed in the darkes part of the sky for my home, the eastern sky.
Due to the vibration prone location of my telescope on the top of our house, I had to throw away 2/3rds of the individual exposures due to trailed stars, so I ended up with only 22,5 minutes of data. Another possibility is, that the guiding didn’t work properly, calibration was suspiciously short.
Anyways, here is the Andromeda galaxy at 1016mm focal length, Nikon D750, 45x30s, ISO 1600, Astro-Physics 127mm f/8, Meade LXD 650 mount.
Venus at 4%
Today Venus was a very delicate crescent, with only about 4% of it’s visible disc illuminated by the sun. I used the 127mm f/8 refractor with a 1.4x teleconverter and took a number of images using the Nikon D750. 20% of 46 individual images were used to create this image using the software Autostakkert:
Testing a new guiding setup
This evening I did a quick test under the stars to see, how iAstroHub 3.0 works with my setup.
Apparently it works quite well, though I need to test with longer exposures.

Mercury Transit 2016
Today the tiny disc of mercury crossed in front of the sun. The weather didn’t cooperate fully, and I had to switch mounts as the Meade randomly stopped tracking in RA, and the WiFi router for the roof didn’t work as expected and tested… but I was still able to get some decent images… Read More
Jupiter and Galaxies
At the beginning of the evening, a short session imaging Jupiter, then I switched over to some galaxies.
This is a short animation made from multiple AVI sequences:

M13, M5, M57
In spite of bad seeing and strong gusts of wind I did set up the big refractor to do some astrophotography. I spent quite some time to get things running – in the end the spring galaxies were already too far west in the glare of the train station, so I switched my targets to two globulars and a planetary nebula. Here is a list of what went wrong:
- I wasn’t aware that the D750 uses a non-standard USB port on the camera, I had to search for half an hour to find the original cable
- the laptop I usually use has been upgraded to Windows 10, installing the drivers for the guiding camera did not work
- on the backup laptop guiding with PHD worked, but Backyard Nikon crashed and/or got no connection to the camera, I tried many combinations of USB extension cables, USB ports, removing the SD card, formatting the SD card, upgrading to BackyardNikon 1.0.5, in the end I focused using live view of the camera and used the built-in interval timer of the camera to shoot 30 second exposures…
- the seeing was really terrible, making focusing difficult, and bloating the stars during the exposure
- for reasons unkown (user error?) the quality setting on the camera was changed to FINE, so I only took JPEG images instead of NEF( Raw)
Preparing for the mercury transit
Today I was making sure everything is in working order for Monday’s transit of Mercury across the sun.
I was able to fix the issue of the declination runaway motor of our club’s LXD-650 mount, and took some images using the 127mm refractor with a 1,4x teleconverter.
The 95% Moon
Even when the moon is almost full (95% in this case) there are interesting features to be found near the terminator: