Why is the left side of my live stack so bright?

[kgeissler]

First, here is the screen shot: https://imgur.com/DpsREYu Second Screen shot with grainy pic: https://imgur.com/loBDU3C

As you can see the left side of the image is very bright. If I adjust the black level to make it disappear, the image gets very grainy. If I adjust the mid level, everything is washed out. Any idea what is causing this? I do have street light in front of my house, but I have me scope set up in the back. The scope can't "see" the street light because it is blocked by my back porch. Could this be light from the street light? Or am i doing something wrong in the app? I am a beginner at this. Any insight would be appreciated.

[GoFraRo]

Hi,
it looks to me for a light leak or straylight.
From the provided picture I can see that the cam is a ASI294MC. I also noticed a strong drift and field rotation in the stacked image and that you do not save single images. Looking into the single files could help to detect, whether this illumination happend once / in a while / or constantly.
It would be also helpful to know the scope you use. A Mak or SC is prone for straylight if not using a shield. Newtonians are different beasts. Usually the back of the main mirror is uncovered and any brighter light source from behind gives strange reflections. Newtonians with a tubular frame are open for any straylight if not protected with a cover.

Gottfried

[kgeissler]

Thanks for the info. I have a Skywatcher Virtuoso GTI 6" Dob.

[GoFraRo]

Thx for the info.
A Flextube. You definitely need a so called light shroud. Check here pls as an example https://astrozap.com/collections/light- ... ght-shroud

Unfortunately, all of them start with 8". But, I'm pretty sure you can DIY or get one custom made by your local tailor

Flextubes are great, but prone for straylights and other influences like dust, dew and other stuff. For visuell observations mostly ok, but a astrocam can capture more than the human eye, even straylight (i.e. from the Laptop or Smartphone screen beside your scope).

Gottfried