Blur on specific spot 5442-ZE

[d5775927]

I have 5442-ZE which works very well, it's installed outdoor without any roof.
However, I follow the wiki and used the dialectic grease and self healing tape.
Recently, I noticed that at night there is an area that is blurred (even without motion), the blur is only visible at night (also visible when IR is off).
Attached a picture.
I tried cleaning the lens, twice, it didn't help.
I tried to zoom in to the max (it's a varifocal) and then the blur disappeared.
When I zoom out, the blur appeared.
What can it be (the blur shape is quite rounded, possibly a water drop that got inside some how)?

 

[bigredfish]

Probably some object or light just out of the FOV that is reflecting light in such a way that the lens cover is picking it up (like a street light). Those can be hard to track down unless you can physically move the camera to point a different direction and see if it disappears..

 

[d5775927]

Probably some object or light just out of the FOV that is reflecting light in such a way that the lens cover is picking it up (like a street light). Those can be hard to trck down unless you can physically move the camera to point a different direction and see if it disappears..

Very possible, I think the city changed the street light (maybe replaced the light bulb) recently, will try to move it a bit, to see if the issue persists.

 

[samplenhold]

I tried to zoom in to the max (it's a varifocal) and then the blur disappeared.

This is a classic reaction to lens flair. Change the focal point and the sport moves or goes away. It is not something on the lens. It happens when it is dark and you are getting some light coming into the lens that flairs into this spot. Sometimes changing the orientation just a little, like angling the cam down a little or to the side a little, will help. Not necessarily having to move the whole cam and mount somewhere else. Also sometimes a visor can help.

 

[Flintstone61]

here is a moving lens flare. I get them in certain conditions as lighting conditions change as the day goes to night.

 

[samplenhold]

^ That is NOT lens flair. That is definite proof of space aliens flitting around your home. Look out!

 

[ThomasCamFan]

I had a random blur on a Dahua camera (boobie dome). A bit of hair-pulling was involved while I chased the problem. It was just condensation inside the camera that only appeared under certain temperatures/conditions. Took camera apart, dried the desiccant bag and allowed the internals to dry out. Problem never returned.

- Thomas

 

[Flintstone61]

desiccant bag, oh yeah...i have 2 cams that need the " treatment" i couldnt remember what the bags were called.

 

[Phil.g00]

I have just tried an experiment that seems to resolve in-camera condensation unobtrusively.
It was far worse than what you are seeing.
In the past, I once used bath flakes, not bath salts. Bath flakes are magnesium chloride as opposed to bath salts which are Epsom salts ( magnesium sulfate).
I found bath flakes the most hygroscopic substance I have encountered. If I spilt some out of the sealed bag, they would turn to liquid within a day by absorbing the moisture out of the air.
This last week I bought a brand new camera, still sealed and boxed, but the lens fogged up inside within an hour of testing it on the bench. Putting the camera in the sunshine cleared the fogging, but it reappeared when out of the sun again.

So I bought 1kg of bath flakes and an oven tray. I baked the bath flakes on low heat until they became an anhydrous powder in the oven. (Do not use high heat as it releases a gas if it melts). Stir it up every so often to keep it like a washing powder consistency. I let it cool a bit, put a few napkins on top of the powder and put the camera on top of the napkins.
The camera has its SD card flap opened. Then I put the ensemble inside a sealed plastic bag with a RUUVi* and put it in the cupboard.

* A RUUVI is a Bluetooth thermometer, hygrometer& air pressure sensor. It measures absolute humidity, not relative humidity.

Within a day, the absolute humidity was 13.8% (down from 53%). I tested it for fogging again, and the lens never fogged at -7 deg C.
( I put the sealed bag and contents in my freezer, then opened it and checked).
But to be sure, to be sure as I didn't need the camera in a hurry, I repeated the exercise. This is the second day, and the humidity has dropped to 12.9%.
I intend to keep the camera bagged up like this for a week to ten days, as I think drying out the internal desiccant bags in situ may take a bit of time.

 

[CCTVCam]

TBH Phil if they're really anhydrous, I doubt you need to risk baking them. Probably simply sealing the camera in the bag with them would draw the moisture out anyway. Probably safer than risking Chlorine gas escaping from the oven. If they want wter they want water. I get condensation in my pantry. Simply standing a small dish in there with some salt in it draws water out to the point where eventually the dish has a 1/2 inch deep lake in it if I don't change the salt 1st.

 

[Phil.g00]

TBH Phil if they're really anhydrous, I doubt you need to risk baking them. Probably simply sealing the camera in the bag with them would draw the moisture out anyway. Probably safer than risking Chlorine gas escaping from the oven. If they want wter they want water. I get condensation in my pantry. Simply standing a small dish in there with some salt in it draws water out to the point where eventually the dish has a 1/2 inch deep lake in it if I don't change the salt 1st.

The crystals aren't anhydrous, they are very hygroscopic.
Since I made the post I read somewhere on the web that they can absorb seven times more water than silica gel.
Baking the water content out of the crystals makes the crystals into an anhydrous powder.
Doing it at about 200 degrees C doesn't release gas.

 

[d5775927]

It took me some time, but eventually moved the camera a bit.
It seems the blur moved as well - in the same direction to which the camera moved, so, seem my first assumption is correct - internal condensation?

 

[wittaj]

No it is the blur moving from the light source being in a different location. Maybe the light above?

It is really easy to create this blur with a PTZ and watch the blur move as the camera moves until the source is out of the field of view.

Move the camera to a completely different field of view and see if it is still there - I suspect it won't be.

 

[d5775927]

No it is the blur moving from the light source being in a different location. Maybe the light above?

It is really easy to create this blur with a PTZ and watch the blur move as the camera moves until the source is out of the field of view.

Move the camera to a completely different field of view and see if it is still there - I suspect it won't be.

Will try to move it a lot more, to face away from the light source, probably will happen after the weekend.

 

[wittaj]

If it is the light above, you could prove this by putting your hand over the camera in between the camera and the light source and watch the blur go away.

 

[d5775927]

If it is the light above, you could prove this by putting your hand over the camera in between the camera and the light source and watch the blur go away.

I need a high ladder, so I prefer to do it in the day (though the result ia only visible at night).