Strange artifacts on my images .... what is really causing the problem?

[SlimPaling]

Hi ..

I recently did a short run of 6 x120sec exposures (using the Lum filter) of Comet C/2020 R7 using a scope at a well known facility in Chile.

I knew that the Moon was quite close to the comet but I just wanted to see if I could spot the comet on the resulting images so I expected some interference from the light of the Moon but the wasn't a major concern for me.

However, when I did some initial basic stretching of the resulting images I could see some very strange dark patterns all over each image ... to me the look like some tracks left by wold animals. All of the images had the exact same defects.

Does anybody have any idea why the glare of the Moon should produce these strange patterns? I haven't bothered to even try to remove them in PixInsight as I don't think anything will work.

I am attaching one of the images to show what I mean.LUM 1.tif

Cheers Mike

LUM 1.tif

Edited July 14, 2022 by SlimPaling
missing file

[Cornelius Varley]

Can you upload the image as either a jpg or png so it can be viewed within the browser.

[Ohgodwherediditgo]

Looks to me like the dew heater failed.

[SlimPaling]

2 hours ago, Cornelius Varley said:

Can you upload the image as either a jpg or png so it can be viewed within the browser.

I have now posted ( Hopefully!) a jpeg version of one of the files ...