Weird case of infrared reflection

[Muiser]

I have an AXIS P3225-LV Mk II Network Camera.

It is there for many years, and when I installed it, the image was perfect with daylight and also at night with the IR lightning.

But recently I discovered that the image was not good anymore.
There was dust on the inside of the plastic bulb of the camera.
I cleaned all the dust from the plastic cover (inside + outside).
I cleaned this cover very carefully with water and then dried it very carefully. I did this already twice to be sure I did it good.
I mounted everything back in place as before.

Now, the image in normal daylight is perfect.
Now, the image with IR lights (the camera has three IR lights) and WITHOUT plastic cover is perfect.

The image with IR lights + plastic cover is like in the attachment (beeld.png).
It looks like the three infrared lights are reflected in the image.

What could be causing this effect?

 

[wittaj]

It is either a tiny dust blob or the gasket is rolled/failed and letting IR in.

 

[biggen]

It’s dust/junk in the dome. I used to have those cameras years ago. Switched them all out for Dahua 5442s.

 

[Muiser]

You are writing "dust in the dome". But where exactly should I found that, I do not see any dust?

 

[biggen]

You are writing "dust in the dome". But where exactly should I found that, I do not see any dust?

Gonna be tiny dust motes on the inside of the dome. You'd have to take it down, take the dome off, and clean it with a lint free cloth.

 

[SpacemanSpiff]

Another item to look for... dome cameras typically have a foam-like ring around the outside of the lens. You should be able to move the ring (careful not to move the lens, too).

When the dome is on, the foam ring should press against the inside of the dome to isolate the IR interior reflection from entering the lens.

If the foam ring is present, slide it off the end of the lens (just a little bit). When you put the dome back on it should make contact with the foam ring

 

[Muiser]

Another item to look for... dome cameras typically have a foam-like ring around the outside of the lens. You should be able to move the ring (careful not to move the lens, too).

When the dome is on, the foam ring should press against the inside of the dome to isolate the IR interior reflection from entering the lens.

If the foam ring is present, slide it off the end of the lens (just a little bit). When you put the dome back on it should make contact with the foam ring

I think I do not see a foam ring, maybe it is missing.
I have a new picture in attachment.
Should there be a foam ring and is it present on the picture?

 

[biggen]

I think I do not see a foam ring, maybe it is missing.
I have a new picture in attachment.
Should there be a foam ring and is it present on the picture?

It's been a while since I took one of these apart but is there no foam ring built into the dome either?

 

[SpacemanSpiff]

I think I do not see a foam ring, maybe it is missing.
I have a new picture in attachment.
Should there be a foam ring and is it present on the picture?

Not sure if yours ever had one from the factory. First time I became aware of their existence was after I knocked one off the lens while trying to aim it.

I cant say with 100% certainty that I've witnessed a foam/rubber ring on every non-ptz dome cam I've worked with.

Any thin packing foam sheets around the house for a DIY IR seal? Would not have to be pretty (at first) to test the theory on your conundrum.

Small thick rubber band might work... I see these (at time) on produce at the grocery store