There was quite a bit of discussion regarding image banding, the reason for noise generation, and the bright or dark spots on an image. Sadly those 'conversations' are burried somewhere in this massive thread
In precis, AFAIK, the microbolometers in the Ex series are all the same but there MAY be some 'binning' of units depending upon the number of failed pixels and/or arifacts detected. I say may, as most microbolometers that have been tested for dead pixels passed the required 99.8% active specification for such a FLIR sensor array. It may well be that the E8 gets the very best performing sensor as its higher resolution may show artifacts more etc. No proof of that though.
In standard E4 rig, any issues with the microbolometer are effectively countered by the averaging and processing ofr the 4x4 pixel clusters used to create an 80x60 image. When you release the cameras full potential you may see issues that were previously not visible. This is a potential penalty for running the E4 beyond its specs but such occurances appear to be so minor or rare as to be of no consequence for most users.
The issue of bright and dark spots on an image have been diagnosed as dust on the sensor in many cases. Some users have blown the dust off of the sensor but I advise some caution here..... removing the lens (using the correct tool!) DOES give you access to the microbolometer faceplate on which the dust resides, but using an air duster to blow on it is a risk if done carelessly. An appropriate coated optics rated air duster that does not contain agressive chemicals should be used (if its designed for cleaning computer keyboards...its not likely suitable for coated optics use !) and consideration should be given to the risk of making matters worse by disturbing more dust particles sitting around the optical block and the sensor with the jet of air. You could end up with a 'snow storm' on the sensors face ! Normally it is best to dismantle the camera and remove the parts that surrond the microbolometer in order to give it a proper optical clean using filtered dry air at an angle rather than direct into the face of the sensor. It should also be considered that firing a powerful air duster directly at a thin optical window structure can break it
so avoid any high pressure air lines as used for workshops ! Dismantling the E4 optical block is not for the faint hearted especially if you do not do such activities for a living.
If there are dust spots visible on the microbolometer at 320x240, but not at 80x60, you cannot use dust contamination of the microbolometer sensor as the reason for exchange when returning a unit (think about it
)
Home
Help
Search
Login
Register
Poll
