Michael‘s Astrophoto Blog

The primary focus of the C9.25 at 2350mm in combination with the sensor size of my ASI 294 is giving a field of view that turned out to be a nice fit for imaging most of the spring galaxies.   However, there are a number of objects that do not quite fit. So I spent a few nights end of April to image a with the 1/6.3 reducer. This is giving a slightly larger field of view. More suitable for some of the larger objects. In addition to the larger galaxies I tried some groups of galaxies. Here it was a bit harder to get a good fit. HCG 44 may actually be better without the reducer. The famous Leo triplet is too big to fit within the FOV - so I captured only two of them. I think they are beautiful - even as a pair.  For the really huge galaxies - like e.g. the Andromeda galaxy - as well as the large scale galaxy groups even shorter focal lengths would be required. I still need to find a good solution for that. In the meantime I enjoy how these medium sized objects turned out.

Before I started Astrophotography I visually observed several types of objects using filters. However, for galaxies I generally preferred the unfiltered view. While it sometimes may reveal individual features that are invisible without the filter, the brightness of the galaxy is reduced by a lot and I found the overall appearance quite underwhelming.   Therefore I was not quite sure what to expect when taking my first pictures with the dual narrowband filter I had been using before. However, in a clear night with an almost full moon I gave it a shot. Due to the longer exposure times required was only able to take quite few individual frames     per object, but after I stacked them they showed a number of features that are invisible on unfiltered pictures.     Most surprising to me I was the strange beauty of the galaxies in the filtered light. I had never seen them like that before. As the filtered images are enhancing a number of features (mostly H alpha) an ob...

The previous images of the spring galaxies looked very promising. As a next step I hoped to improve them further by gathering more data per object and by further practicing my image processing skills. As I found it too hard to focus my attention to just one galaxy the total number of frames per object is increased only to a few hundred. On top of that I had to exclude a number of frames as the nights end of March turned out a bit hazy leading to bad contrast in the individual images. However, I find the resulting images are a good step in the right direction. In many cases a lot more detail is visible in the Galaxies. 

I am a big fan of galaxies. During spring, when a large of them are visible, I used to spend many nights watching them. Most of them are just fuzzy patches, but if you try a little you can see a bit of structure in some of them. If that doesn’t work it is still fun to see if any small companion galaxies are visible and to check their magnitude on a star map. So I was really looking forward to my first galaxy season as a photographer. Some of the reason why I directly tried to make astrophotography work with my SCT, rather than using smaller focal lengths initially, had to do with my hopes of being able to photograph galaxies.  Fortunately there were a couple of clear nights beginning of March and I went a bit crazy imaging all the objects from my usual observing list.   I started with relatively small numbers of frames per object, in order to get some first overview of all the items on my list, what is possible and which objects are good. That way I took pictures of 40+ galaxi...

As I described in the previous blog my equipment has improved quite a bit over the past weeks. I got a dedicated, cooled astro camera as well as a separate camera and a little finder scope for automatic guiding. After sorting out the initial technical issues, finally we had    a few clear nights to put the new kit to the test.  M33 30x30sec, C9.25 with 1/6.3 reducer, ASI294MC Pro on NexStar Evolution  M1 Crab Nebula, 28x60sec C9.25 with 1/6.3 reducer, ASI294MC Pro on NexStar Evolution  M27 Dumbbell Nebula, 30x30sec C9.25 with 1/6.3 reducer, ASI294MC Pro on NexStar Evolution  IC5146 Cocoon Nebula, 60x60 sec  C9.25 with 1/6.3 reducer, ASI294MC Pro on NexStar Evolution  NGC6888 Crescent Nebula, 30x30sec C9.25 with 1/6.3 reducer, ASI294MC Pro on NexStar Evolution  As visible in the pictures on close inspection I am still struggling with the autofocus.    The guiding doesn’t work really flawlessly in all cases, particularly in high ...