ASI294 MC PRO cooling noise?

Hello guys,

I have been experiencing a noise problem on my 294MC pro camera.

When the TEC cooler is running at high power (say 90%, cooled to -15c at room temp), it starts to show black dots in the middle of the frame.

I know that it's best to keep cooler run at lower power, but I was capturing flats inside and this is the first time I noticed this.

Here's some image for comparison.

TEC %90 (-15c)

dot.jpg

TEC %30 (0c)

clean.jpg

Image processed with defective flats

94580637_10163696043750651_9023122605472743424_o.jpg

Is my camera damaged? or is this a known issue? :

It's normal, you don't have to worry about this.

You could take more light files and flat files, then adjust in the post processing software.

Moson wrote:

It's normal, you don't have to worry about this.

Ok, but how is this normal? it's sometimes there and sometimes not.

In fact, the third picture is 2 hours of data just ruined by 50 flats (1st image)

Some of the members from the Facebook group said that the camera should be cooled gradually otherwise this will happen. Is it correct?

That's a dew/moisture problem. My 294 behaves the same way.

You can avoid it, if you set the target temperature a few degrees

higher (about 20 degrees below environment temperature).

That's not perfect, of course, but better than loosing frames …

As soon as the nights here in Germany are too short and too bright

to take photos, I will try to dry the desiccant tablets and install

a camera window heater. I hope this solves the Problem.