Last week, a CalSky alert email reminded me about a close passage of the International Space Station to the bright Arcturus, in the Bootes constellation.
Alessia was here, so we catched this opportunity to do some "garden astronomy" together, watching the passage while also trying to record it on camera.
The idea was to do two shots: a wide field, with my large sensor ASI1600mm and an 85mm lens, and a narrow field with the telescope.
It was a beautiful, almost hot evening. Unfortunately, not everything went as planned: the ISS was passing a bit further then expected, since I forgot to update my location coordinates in CalSky, so the telecope shooting was missed, and a few technical issues, plus me choosing the wrong recording duration on the shooting program, almost made me miss the passage itself even on the wide field.
But after a few minutes, without even knowing if the recording was actually successful, looking the frames I was able to spot this bright...
As I wrote on my previous post, an exceptionally good weather kept me outside pretty much every night just when Jupiter was at its best.
On April the 7th, during its opposition, I was able to capture a sequence of 4 sets of video captures, each one in RGB. I tried to optimize as much as possible my timings, in order to keep rotational differences between frames under control. This will probably be even easier on a future Planetary Imager release, when I'll implement a scripting interface.
The results are even better than the previous evening.
I was able to take 4 images, and create an animation displaying Jupiter's rotation and its satellites.
A few more summerlike days, and a few more astronomical shots.
It was sunny, and with a very good seeing from Thursday to Saturday night, just in time for Jupiter's opposition, when it's closer to Earth, and then bigger and easier to capture.
But since I wasn't very happy with my previous Jupiter shots, the first of these three nights I mainly took pictures of the moon.
I began by using my newest camera, an ASI 1600mm: it's more of a deep sky camera, not very suitable for planets and moon: 3.8 µm pixel size instead of 2.4µm of my other camera, an ASI 178mm, and bigger pixels means lower resolution. It also has a much wider sensor, which slows down capturing (and fast framerates is a key element to get high resolution images), but this is also an advantage from another point of view: I was able to capture the whole moon disk in just a single shot, instead of the usual mosaic.
This is the result, in my opinion one of my best looking images ever:
This weekend weather in London was quite amazing: sunny, a bit too windy, but sky almost perfect. Seeing forecast was also encouraging, so on Friday evening I took a chance to shoot at Jupiter.
It was a bit of an unlucky evening: firstly I discovered that I forgot my red dot finder on, so the battery was totally drained. After struggling for a while trying to align my GoTo mount without it, I decided it was worth to leave the telescope alone for a few minutes (my garden is easly visible from the street... I didn't want to do it unless absolutely necessary) and got back inside to find new batteries.
After everything was aligned, and I was ready to observe and record my images, I noticed that the image wasn't exactly satisfying at the eyepiece. When I replaced the eyepiece with the camera, the very unfocused image revealed me why: some tree branches were in the way, and of course the image was deteriorated from the interference!
I looked around me to see if I could find a better sp...
I'm currently living in a house with a very nice backyard, right outside London. Still a lot of light pollution, but it can be manageable, and useful for testing my equipment before running to darker locations.
This was meant to be a (L)RGB shot, but light pollution and humidity made the blue and green channels pretty useless, while red channel produced quite good results
Last friday night the sky was finally very clear, so I made a few shots.
The brilliant Orion Nebula (M42) is very well defined...
I recently bought a new smartphone, a OnePlus 3, since my Nexus 6 was pretty much dead, turning off pretty much everytime I did something else than keeping it in my pocket.
I was particularly interested in the "manual controls" feature of the OnePlus, including the ability to shoot up to 30 seconds, particularly convenient if you want to use it for astronomy.
It turned out this really works out well!
I just did a few tests, but the results are very promising.
It's been a while since my last updates. I recently moved to London, changed work, and.. changed astronomical instruments too. I'm planning to buy an ultra portable 300mm dobsonian soon, probably the best choice since I would like to travel as much as possible with it - back to Italy, or maybe to the southern skies.
But I also wanted a "quick" telescope, lightweight and simple, something that I could bring out in the garden in a very few minutes, and even better, ready for planetary imaging, so in the meantime I also bought a small Maksutov-Cassegrain telescope, a Celestron Nexstar SLT 127. I also got a new camera, USB3, with very high resolution and wider field than my previous one, a ZWO ASI 178mm, still a monochrome camera, but this time with RGB filter set.
Given the smaller aperture, I'm not expecting really great shots, but my previous setup much heavier, so I spent very little time observing and shooting, which in turn means I didn't really got it to its maximum potential....
A very convenient tecnique in c++ programming is the one known with many names: "d-pointer" (found in Qt/KDE contexts), shadow pointer, "pimpl", opaque pointer. Basically the idea is to hide all the private details of a class in a forward declared private pointer, which will be the only real private member of the class. Since this member will never change, this will guarantee binary compatibility among different versions of a library.
But there are other advantages in using d-pointers: one is compilation speedup during development (usually if you change a private member of a class, the header changes, and you have to recomplile all units using that header, while with d-pointer you change only the .cpp file), and another is code cleanup: you will have very compact header files, describing your class public interface without private stuff pollution. Also, sometimes you may want to add your d-pointer definition in a separate header file, ending up with three well defined files:
The classical approach is to create a plain raw pointer to a forward declared class, initialize it in the constructor, and delete it on the destructor. A nice addition is to have the private class be a nested type, so that you can avoid polluting your IDE class list.
It has happened in a few occasions, to launch a command in a shell only after a command in another shell has successfully finished (for instance, after a long task like source code compilation, i want to launch tests on another shell).
This sunspot was particularly big, so I waited for the best moment to try and catch it.
Seeing wasn’t great, and my solar filter was a bit damaged, but the final image doesn’t look too bad anyway.
Unfortunately, this will be the last image for a while.
Just a few hours later, someone opened my car, and took away my HEQ5 mount, together with all my eyepieces and the camera I used for all my planetary shots.
I’ll also be relocating in a while, so I’ll wait a few months before buying a new setup.
If someone is interested, I’m selling my current main optical tube here: http://www.astrosell.it/annuncio.php?Id=70007