What's going on here, any thoughts?

Ant0nio (Tony) · #1 10-02-2019, 01:40 AM

Any imaging I've done for the past couple of nights has looked like this. I was thinking moisture content or high cloud. It cant be processed out, any ideas?
Cheers,
Tony

VPAstro (Andrew and Cam) · #2 10-02-2019, 07:58 AM

Looks like frost on the sensor to me. What temp are you cooling to.
I have the same problem on my SBIG. I change my desiccant all the time, but still have the same problem. I can't really cool below zero any more without this issue.

Ant0nio (Tony) · #3 10-02-2019, 07:33 PM

Quote:

Originally Posted by VPAstro

Looks like frost on the sensor to me. What temp are you cooling to.
I have the same problem on my SBIG. I change my desiccant all the time, but still have the same problem. I can't really cool below zero any more without this issue.

Thanks for the input Andrew, I've been cooling to -10 with no problem until now, night time ambient is usually around 22 but humidity has been quite high lately. Sounds like I should look at changing the dessicant on the strength of this.
Tony

markas (Mark) · #4 11-02-2019, 03:39 PM

Check to see if your camera has a window heating function. All my Moravians do - and without it there would be many nights lost to frosting of the window....

Mark

brisen (Brian) · #5 11-02-2019, 05:01 PM

Did you notice any dew on the mirror or front objective of the scope? I was just north of Gympie on the weekend and there was a lot of moisture around later in the evening and early morning. I have seen this happen with dew settling on the front when the dew heaters weren't on.

Brian

Ant0nio (Tony) · #6 11-02-2019, 06:58 PM

Thank you Andrew,Mark & Brian. I believe I can put this down to frosting on the front window of the camera as per this post on Cloudy Nights;https://www.cloudynights.com/topic/2...on-my-st8300m/
Regarding the heating option Mark, as far as I know there isn't any but I believe SBIG introduced a "window heating strip " as a customer installed upgrade to combat the problem but I can't find any solid info on it.
As for dew forming on the objective Brian, there was just the beginnings of it but everything else was pretty much soaking wet ( I should have known better

) I think the most likely cause was adding a spacer to the FR which let some moist air into the image train

, I won't be doing that again. I'll change the dessicant & keep the image train sealed whilst outside in future. I appreciate your input guys, you've helped me solve this.
Cheers,
Tony