Ekos Blues - Astroberry and Ekos Issues to avoid

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Starting with astrophotography was quite a steep learning curve for me. Though I felt that I had a reasonably good grasp of many of the general concepts - the reality of making all components work well together was something different. At the beginning large portions of the observing nights were spent battling all kinds of technical issues with the new equipment. 


In this post I want to describe some of the bigger or smaller issues and pitfalls I encountered. Many of them may be specific to my situation and equipment, but perhaps it gives some idea on what to look out for.


Don’t trust Indi device defaults


The Indi drivers for most devices come with a large number of device settings. As a beginner I was not always clear on what each of them does and/or why I may want something different. My assumption was that the default settings are good enough to get started and changes can be left for fine tuning at a much later point in time. However, when taking and processing the first pictures with the ASI 294MC Pro camera - I got results like the following:


One of the first processed pictures I had taken with
the new ASI camera and Ekos.
A very strong blue cast is visible.


The raw images looked ok in the Ekos viewer and I did processing the same way as with the DSLR pictures. However, I got a nasty blue cast in the outer region of the pictures. It turned out that all images taken, including the calibration frames had a blue cast that was not compensated during processing. It was not visible in the viewer as it averages out any color offsets, but it became apparent in the processed images. At first I thought the camera may be defective - I was devastated. However, the root cause was that the Indi camera defaults are actually configured for a blue offset.


Indi default settings for the ASI 294
the white balance is shifted towards blue


Setting the white balance values for red and blue both to 50 resolves this issue. 


A similar issue occurs with the ASI 120MM mini guiding camera. Every now and then indi failed downloading the picture, which meant that the guiding was left without current information for some time, degrading the overall performance. After researching camera firmware versions and testing different the USB cabling it turned out that the actual root cause was that default Indi setting for data transfer of the 8 bit camera was 16Bit - changing that to 8 bit solved the problem for me.  


Astroberry Wlan connectivity 


In most cases I am accessing to the Astroberry via Wlan. However, at times it became completely unreachable just after connecting the astro camera via USB3.  At first I thought that the Rasperry crashed due to power issues or issues with the USB port. However, that wasn’t really the case. Apparently the USB3 connection is interfering with the Wlan signal rendering the Rasperry unreachable. I fixed that issue by adding a Wlan repeater that offers an Ethernet cable connection as well. 



Astrometry focal length settings 


Being able to plate solve the images taken by the camera is important for the mount alignment and centering of the objects.  At the beginning plate solving kept failing for certain configurations cutting me off from a key component of the Ekos workflow. I bypassed it by directly star aligning the mount and then manually centering objects, but that was less than ideal. 


It turned out that due to a longer distance between reducer and camera the effective focal length was different than what I expected. That became obvious once the plate solve stopped failing. To get there I turned the stetting "use scale" off. 





With that setting the solver is no longer limited to the configured focal length and just finds the actual focal length and the coordinates from there. It potentially slows down the solving process if you are far away, so it may be worth trying to play with the limit settings instead. However, I was satisfied with the speed of the plate solving and just kept it turned off. This way I don’t need to bother anymore to change the focal length in the Ekos settings when switch between configurations e.g. with or without reducer. After the first plate solve Ekos knows and uses the actual focal length. 



Debayering of images in Fits viewer


Seeing the colors of the deep sky objects right away was one of the thrills when starting astrophotography. On the Astroberry this feature is actually turned off by default. I enjoyed turning it back on and it works just fine - mostly. Apparently there are situations where it can lead to a complete Ekos crash. 




I don’t know if that will,still be the case with a Rasperry that has more memory, or if this is going to be fixed so that just the image display fails gracefully. For now it makes Ekos way too unstable for my taste. I turned debayering off and went with the "limited resources mode".  



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