Hey guys!
I finally had a chance to make some pictures of the sky. Munich's weather is often challenging, and the Moon isn't very helpful in this regard either!
I bought the iOptron tracker, as well as a cheap and yet excellent lens, the Super-Takumar 200mm f/4 from Pentax. This is an old school lens from the 70', I think, which is often recommended as an affordable quality astro lens.
Here is one of my first test, the Andromeda galaxy. It's far from being perfect, but as a first try it's really rewarding to get just a little glimpse of something so big and far away! When you think of all the things that are in this pictures: billions of stars, planets and, perhaps, lives... And when you think that the light that hit my camera's sensor traveled about 24,000,000,000,000,000,000 km during 2.5 million years... Wow.
This 20 minutes long exposure is a stack of 40 "light" photos (as well as some "dark" frames used to diminish noise) taken with an equatorial mount (iOptron Sky Tracker Pro) and aligned together in DeepSkyStacker software. Single exposures were 30 seconds long, at ISO 1600 and f/4.
The big bright halo in the center is the core of the galaxy. You can see a bit of the arms of the galaxy around the core, as well as 2 satellite galaxies: Messier 32 (the brightest halo at the left of Andromeda's core) and Messier 110 (the faint halo at the bottom right). Andromeda is the closest galaxy to the Milky Way, and will collide with our galaxy in about 4.5 billion years... we have time to prepare!
Unfortunately, I'm still a beginner and did several mistakes:
- The tracking of Polaris was not accurate enough, and we can see a bit of star trailing. For those who are not familiar with tracking mounts, it consists of a motor aimed at the Polaris star, and rotating at the speed of the Earth, in order to eliminate the movement of our planet and make long exposures of the night sky.
- The stacking: I probably failed something, because there is a weird fabric-like pattern in the picture. Someone told me it might be due to the de-bayering of the picture, but I have no idea what it means! I'll look into that later
- The exposure: the exposure, 20 minutes, is not enough to bring all the details out of the galaxy. 1 hour would have been better! Not to mention that Munich is a light polluted area, even in the city park, and that the moon was quite bright that night.
- The aperture I used, F/4, produced quite a lot of vignetting. In astrophotography, it can be removed quite easily, but I need to spend some time on this. Perhaps next time I'll use an aperture of f/5.6, which seemed to produce better results on my test shots.
But on the other hand, I think it's a good start and I have a lot to learn, both in the setup itself and the post-production.
The version I posted on Instagram is a bit different, the enhanced filters I used brought some of the details in the arms back:
As a comparison, here is a picture taken by Hubble, NASA's space camera. You will notice that their picture is infinitely better than mine, but hey, I can't afford to send my Fuji into space
To be continued!
Konzy ⠀