Tag Archives: “Jellyfish Nebula”

Water on Sensor: ZWO ASI-1600MM-Cooled

Clear skies

I’m doing some routine imagine and already captured a couple of images, subs and moved on to a new target, the Jellyfish Nebula.


After the first sub, I noticed something weird in the result and felt like some dew or water started building up in front of the sensor, yes it was in the front of the sensor, not in the camera protect window filter. It ruined a good night of imaging and the next day.

Cleaning the camera

I looked at the problem. Researched on how to clean it up and a good thing that ZWO has a very good documentation on how to do it right.
One thing I noticed on the sensor when I was cleaning it that the marks we’re not actually water. Not sure about this but the reason to say this was I used a hair dryer and it didn’t go away. I used distilled water on a cotton swab to wipe it and it didn’t go away. I have to use an alcohol to remove it then wipe it again with the distilled water. I think I did a pretty good job here but I kind of messed up in cleaning the glass on the protect window. I felt that there was some scratches and some dirt were not removed. Also looked at the desiccant tablets and it was in a very good condition but replaced it anyway.


Tested it quickly and good to see that there we no sensor dirt but can clearly see the dirt on the glass protector.

ZWO ASI-1600MM-Cooled Camera
ZWO ASI-1600MM-Cooled Camera

The water or whatever it is, is clearly visible in the side of the sensor.

Water in sensor ASI-1600MM-Cooll
Water in sensor ASI-1600MM-Cooll  Full size

On the image above, the water is clearly visible from the image taken.

Whirlpool Galaxy
Whirlpool Galaxy Full size

I can see the dust on the camera protect window but the sensor looks clean and went ahead and imaged the Jellyfish Nebula. The result are okay enough that most of the dust we’re unnoticeable.

Jellyfish Nebula
Jellyfish Nebula  Full size
Camera Protect Window Replacement

Right now the glass replacement is still not available from ZWO but once it’s available then it’s something that I need to work on. One thing that I have learned is if it doesn’t require cleaning then just leave it alone. Don’t even touch it as it might be ruined.

D32 AR Protect Window

I contacted Sam from ZWO and he and Vanessa was very helpful.  Even if it’s not available on the website, they offered me to send a new one.  Will be receiving it tomorrow and hopefully I’ll get a chance to work on it and replace the camera protect window.