I took theses images about two months apart M15 and Orion Nebula,they are live stacked then saved as seen in sharp caps, as you can see both show egg shaped stars, Could this be a collimating or tracking issue
My scope is a skywatcher mak newt 190
Camera Altair 294c pro tech
Guided 290 go pro
Help with Egg shaped stars
Help with Egg shaped stars
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Re: Help with Egg shaped stars
Hi,
it's kind of hard to tell based on the images because of the low resolution – perhaps you could share links to higher resolution versions stored on some other image sharing site like Flickr.
As a general guideline, if the star shape is consistent all across the image then it's quite possibly a guiding problem. If it varies in different areas of the image then it's more likely to be an optical aberration (collimation problems, coma, flattener separation distance, etc).
cheers,
Robin
it's kind of hard to tell based on the images because of the low resolution – perhaps you could share links to higher resolution versions stored on some other image sharing site like Flickr.
As a general guideline, if the star shape is consistent all across the image then it's quite possibly a guiding problem. If it varies in different areas of the image then it's more likely to be an optical aberration (collimation problems, coma, flattener separation distance, etc).
cheers,
Robin
Re: Help with Egg shaped stars
I've opened a flicker account and posted there
https://www.flickr.com/photos/191795874 ... ed-public/
https://www.flickr.com/photos/191795874 ... ed-public/
hopefully it will work
Any hints and tips also on general image quality greatly apricated also.
Thanks
https://www.flickr.com/photos/191795874 ... ed-public/
https://www.flickr.com/photos/191795874 ... ed-public/
hopefully it will work
Any hints and tips also on general image quality greatly apricated also.
Thanks
Re: Help with Egg shaped stars
It looks like all the stars are oblong from the bottom left to upper right side. Perhaps a tracking error or cord snagging?
It doesn't appear to be radiating from the center which would indicate back spacing issues.
It doesn't appear to be radiating from the center which would indicate back spacing issues.
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Re: Help with Egg shaped stars
Hi,
This looks like mount / tracking problem as the oblong is in the same direction all over the frame. If this was an optical issue the oblong stars usually tend to be at the edges of the frame and point towards the center. Are you using guiding?
-Chris
This looks like mount / tracking problem as the oblong is in the same direction all over the frame. If this was an optical issue the oblong stars usually tend to be at the edges of the frame and point towards the center. Are you using guiding?
-Chris