Dome Camera too close to reflecting surface.
Mounting an IR dome camera underneath an eave without enough vertical clearance between the dome and the eave, may cause the IR LEDs to reflect off of the bottom of the eave and bounce back into the lens, ruining the shot. This same effect can be duplicated in a variety of mounting scenarios. Keep the angle of projection of the IR’s in mind when mounting your security camera. Bounce back from objects too close to the IR is extremely common.
Scratches on Dome Camera Outer Cover May be hard to detect.
Testing was done with an integrated IR CCTV Dome Camera to see how these very issues impacted images during day and night. The dome camera was tested with light and heavy fingerprints, dust, dirt, and also with slight scratches. To the eye, some of these issues were not noticeable unless carefully inspecting the camera and could easily go overlooked in the field. Even slight smudges, dust, or scratches had significant negative impact on image quality at night with IR on, reducing details and blurring portions of the FOV (Field of View), even if these issues were not present during the day, or visible on the dome camera cover itself. Very little force was required to scratch the polycarbonate dome.
Fingerprints on the inside or outside of Dome Cameras cover.
Again very hard to actually detect but will cause significant issues. Fingerprints can get on the inside of the dome camera cover during installation just as easily as the outside. Make sure the inside of the dome cover is clean before re-installing. After placement, the angle-of-view and focus is set, a final cleaning should be done before closing the cover.
Placement of Black O-Ring around lens is not correctly seated or off-center.
When reinstalling the dome camera cover, make sure the O-Ring that surrounds the actual lens is placed so that it keeps any IR from bleeding through. This will cause a glaring effect on the image. The ring should be snug against the dome cover all the way around.
Dust or Dirt, etc, on Dome Camera Cover.
This seems obvious but is very common. Dirt builds up on the dome cover but is barely visible to the naked eye. The image will still be great in the daytime but as soon as the IR’s kick on you will see a plethora of issues. Be careful cleaning the cover as well.
Shooting IR Camera through glass is not optimal.
IR LED’s will bounce back when going through glass. IR Cameras that are observing an external (outside) area should be installed outside. Installing the camera indoors and shooting through a window will not work.
Use a Scratch Free cloth to clean your CCTV Dome Camera.
Cleaning your dome with a rough or dirty rag may do more harm than good. The poly-dome cover will scratch easily and should be cleaned gently with the appropriate material.
Wrong Camera Selection
In many areas, a problem can be solved by switching to a Bullet style Security camera. Some areas are not optimal to the profile of a Dome style Security Camera. Check with your Dealer or distributor for options. IR Dome Security Cameras are extremely popular due to ease of installation and rugged form but may not be the best choice for all CCTV Camera applications.