Dealing with camera noise

If you read “Why camera noise matters” you’ll know noise can be a problem. You may also be wondering what to do about it.

Allow me to offer three suggestions:

1. Buy a camera with lower noise.

Easier said than done. Camera-makers don’t always make their noise levels available, especially if they’re nothing to write home about. And don’t go thinking it’s all just sensor-dependent: some of the noise comes from the camera electronics rather than the chip itself. That’s why, as a general rule, more expensive cameras produce better images.

2. Average multiple images.

I like this approach. Assuming time permits, grab two images and average them. It takes a little computational effort, especially when you’re in the multi-megapixel range, so I don’t think a smart camera is up to the task, but if you have a PC system it might be a quick way to reduce variation.

3. Lower the temperature.

Much of the noise is temperature related. In fact a good rule of thumb is that noise doubles with every 6 to 8 ^oC rise. So keep the camera cooler and the images will be less noisy.

Stuck for ideas how to lower the camera temp? Well here are two. Mount it on a big chunk of aluminum, or put it in an air-cooled enclosure.

 

Noise can really mess with your images and inspections, but there are ways of dealing with it. I’ve offered a couple of suggestions. If you others, please share.