Milky Way - A longer exposure image

Date2019/02/01
LocationLa Palma / Spain
ObjectMilky Way
CameraEOS6D + Samyang 2.8/14mm
Guidingno
Telescope-
Barlow lensnone
MountEQ6 Syntrek
Cooling-
Luminance6x
Red-
Green-
Blue-
Dark3x
Flat-
Total exposure~15min.

Once more back on La Palma / Spain. I imaged the Milky Way a few times before from this beautiful location. However, up to now I was always bound to a maximum exposure time of about 20 seconds due to the earth rotation. This time I decided to put the camera - an EOS6D with a Samyang 2.8/14mm lens - on top of an EQ6 mount. This way much longer exposure times with a lower ISO value (i.e. less noise in the image) were possible without getting any star trails. I took 6 frames with ISO 1600 á 148 seconds each. The total exposure time is therefore about 15 minutes.

The frames were then post-processed with rawtherapee and averaged using the ImageMagick "convert" tool. In addition 4 frames of the foreground (the house) were taken and also averaged (of course with disabled EQ6 mount). Finally the two pictures were overlaid and merged with the help of a mask using gimp.

To me it is amazing to see the Andromeda Galaxy (M31), the California Nebula (NGC1499), the Orion Nebula (M42), the Pleiades (M45) and the Horsehead Nebula (B33) clearly on this photo. This overview picture gives a good idea of the brightness, size and exact location of the objects compared to each other.

A full resolution image of the result can be found here. Another image without object descriptions can be found here. I am curious to repeat this procedure in summer when the bright part of the Milky Way will be visible again 🙂

Stargazing time on La Palma - Casa Las Flores

It's stargazing time on La Palma again - this time from Casa Las Flores. The little house is located in Aguatavar - close to Tijarafe on a height of about 580m. You have a power supply outside the building, free view to Polaris from both terraces and in July the bright part of the Milky Way is perfectly visible between 22:00 and 4:00 local time. Furthermore you have a coffee maker, a table, chairs, a fast WLAN internet connection and a barbecue. What else do you need? 😀

The image is a single frame recorded with an Canon EOS6D in combination with a Samyang 2.8/14mm lens (15 sec. exposure time, ISO4000) . The post processing has been done with rawtherapee.

Tonight I only test my equipment - for tomorrow I plan to record the bright nebula M8 in the milkyway. So stay tuned for the result!

¿Por qué dormir en un hotel de cinco estrellas si puedes dormir bajo millones de estrellas?

This image of the Milky Way has been recorded in a clear, cold night not so far away from Roque de Los Muchachos. It has been recorded with an EOS6D in combination with a Rokinon 14mm/f2.8 fast lens. The exposure time was 20s with ISO6400. A darkframe has been subtracted later on. The RAW file has been developed using rawtherapee. For correction of vignetting and perspective a lens correction profile from this website has been used (btw. thanks for providing this profile!).

The image is also available in full resolution (3.1MB).

Milkyway photography with the X-T1 and stacking with DeepSkyStacker

In this post I want to show a way of Milkyway image processing which does not require any commercial software product. The idea is to use rawtherapee, DeepSkyStacker and GIMP to develop, align and combine the frames to one final image.


Camera: Fujifilm X-T1, Exposure time: 25sec. per frame, ISO: 1250, Aperture: f/2.8, focal length: 18mm

Quite often it is advantageous to use a high ISO value to get as much details as possible in the available exposure time (before the earth rotation becomes visible). On the other hand one probably does not want too much noise in the image. Therefore, the idea is to take multiple frames at a high ISO value and stack them later to reduce the noise. There is just one problem: The earth rotates and from frame to frame the stars are in different positions. Therefore an alignment of the frames before averaging is required. But then we get another problem: The foreground of each frame moves and so the resulting foreground gets fuzzy in the end. What to do? Continue reading →