Dear Masters of the Dark,
while beeing a bit busy for the last two months (and will be until the end of may), I was able power my rig during the last few nights. I have to get rid of some things that bother me in my images. So I decided to optimize my equipment a bit and some questions in the forum motivated me to do this. But I'm a bit confused about some technical details. So Maybe you can halp me with this.
I am at a point now, where I don't like some things that I see in my images. The star shapes are the main issue here. I tried once to collimate my 8" Newton properly (a simple TS Optics reflector - no UNC) and read some articles/watched some videos to get the knowledge. Then I did the collimation and tried to adjust the mirrors as needed. Soon I realized, that the adjustment range of the secondary mirror seems to be too short to see the details as described in different videos. Anyway, during the last days, I was really dissapointed with the results and yesterday, I decided to set the secondary close to where it was when it came from the factory. Although the mirror adjustment looked not optimal, the effect on the image was really huge. The stars were now much smaller and the quality increased. On one hand this is good, of course. On the other hand , I must be missing a key point in the collimation process, which seemed so easy to me. But it works for now… (room for improvement left)
The second thing I changed was the settings of PHD2. I always looked at the guiding graph and tried to optimize the settings to keep the graph as smooth as possible. Since the introduction of multi star guiding, I shortened the interval for the corrections to about 1 to 1.5 seconds. The graph looked always good. But now I realized, that I had really bad star shapes in my last images. They always were blurry and if you look in the corners of the frames, you clearly see the circular movement of the mount while imaging. So yesterday I decided to trust the PHD2 guiding assistant and left the settings where they were recommended to be. What can I say… The stars are much sharper now and although the graph looked horrible to me, the image quality seemed to improve a lot.
So I don't exactly know if both changes effected the images in a good way or if only one of them is responsible for that.
I plan to get my OAG running properly, too. But thats a bit difficult for now. I may not find the time to do it in the next weeks. Another plan is to optimize the working distance of my coma corrector.
My currently working main rig is:
TS Optics 8" Newton f/4 (all standard parts)
Skywatcher EQ6-R Pro (unmodded)
ZWO ASI294MM
Explore Scientific HR Coma corrector
ZWO Filter Wheel 7x2" (LRGBHSO from Astronomik)
ZWO EAF
SVBony 60/240mm guide scope (f/4)
Altair GPCam3 178MM guide camera
If I look at the images of so many other users out there, The star shapes are really great. A lot of them use similar equipment as me. So what have you done on your way to those beautiful stars? I know, that there has to be a lot of experience. But I feel to get to a point, where standard anwers wont help me much. I have to dig a bit deeper, I guess…
Thanks for your help
CS
Christian
while beeing a bit busy for the last two months (and will be until the end of may), I was able power my rig during the last few nights. I have to get rid of some things that bother me in my images. So I decided to optimize my equipment a bit and some questions in the forum motivated me to do this. But I'm a bit confused about some technical details. So Maybe you can halp me with this.
I am at a point now, where I don't like some things that I see in my images. The star shapes are the main issue here. I tried once to collimate my 8" Newton properly (a simple TS Optics reflector - no UNC) and read some articles/watched some videos to get the knowledge. Then I did the collimation and tried to adjust the mirrors as needed. Soon I realized, that the adjustment range of the secondary mirror seems to be too short to see the details as described in different videos. Anyway, during the last days, I was really dissapointed with the results and yesterday, I decided to set the secondary close to where it was when it came from the factory. Although the mirror adjustment looked not optimal, the effect on the image was really huge. The stars were now much smaller and the quality increased. On one hand this is good, of course. On the other hand , I must be missing a key point in the collimation process, which seemed so easy to me. But it works for now… (room for improvement left)
The second thing I changed was the settings of PHD2. I always looked at the guiding graph and tried to optimize the settings to keep the graph as smooth as possible. Since the introduction of multi star guiding, I shortened the interval for the corrections to about 1 to 1.5 seconds. The graph looked always good. But now I realized, that I had really bad star shapes in my last images. They always were blurry and if you look in the corners of the frames, you clearly see the circular movement of the mount while imaging. So yesterday I decided to trust the PHD2 guiding assistant and left the settings where they were recommended to be. What can I say… The stars are much sharper now and although the graph looked horrible to me, the image quality seemed to improve a lot.
So I don't exactly know if both changes effected the images in a good way or if only one of them is responsible for that.
I plan to get my OAG running properly, too. But thats a bit difficult for now. I may not find the time to do it in the next weeks. Another plan is to optimize the working distance of my coma corrector.
My currently working main rig is:
TS Optics 8" Newton f/4 (all standard parts)
Skywatcher EQ6-R Pro (unmodded)
ZWO ASI294MM
Explore Scientific HR Coma corrector
ZWO Filter Wheel 7x2" (LRGBHSO from Astronomik)
ZWO EAF
SVBony 60/240mm guide scope (f/4)
Altair GPCam3 178MM guide camera
If I look at the images of so many other users out there, The star shapes are really great. A lot of them use similar equipment as me. So what have you done on your way to those beautiful stars? I know, that there has to be a lot of experience. But I feel to get to a point, where standard anwers wont help me much. I have to dig a bit deeper, I guess…
Thanks for your help
CS
Christian