Filtered Galaxies

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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 obvious next step was to combine them with the RGB images. 





I am really liking the results. Seeing red Ha regions together with the bluish star creation regions is giving a good idea of what is going on. In addition to that I find these pictures quite pleasing aesthetically. In future will I try taking narrowband images from all the galaxies that show promising features.


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