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I had an interesting talk with a sales rep that sells nikon CCD for microscopy. She was telling me that a CCD camera that is cooled is much better for fluorescence microscopy (think green/red glowing cells on black background) since there is less thermal noise and hot pixels.

An ordinary CCD from nikon costs $3000, the cool edition is significantly more expensive. The cooler the CCD gets, the more expensive. ie $17 000 for the mid range.

Does anyone know if taking photos at zero degree's help in terms of noise? And how true is this thermal noise and hot pixel thing when it comes to temperature?

Insights would be more than appreciated.  btw nikon makes great scopes and optics, its like the gold standard in science. Crap analysis software though.

Link: Does it make sense to cool a scanner chip?

nito wrote:Does anyone know if taking photos at zero degree's help in terms of noise? And how true is this thermal noise and hot pixel thing when it comes to temperature?

I presume you're talking about ambient temperature, and I'd have to say no. It's a bit like the CPU chip in your pc, which can get quite hot, regardless of the ambient temperature, in a matter of seconds.

With your camera's CCD, it will start heating up (in a manner similar to your CPU, but I'm not sure to what, er, degree)when you open the shutter and commence making the exposure. The ambient temperature will have little if any cooling effect; you'd probably need to apply some form of active coooling to the sensor in order to have any effect.

Cooled CCD’s have been around for a long time and it would appear that the main use is in reducing dark current. This makes a cooled CCD excellent for bio and chemo luminescense, DNA sequence imaging, x-ray imaging, radiology and in particular astronomy.

The following information has been copied from an ad for a monochrome Peltier cooled CCD camera:


This monochrome CCD camera utilizes Peltier cooling to dramatically reduce dark current noise that accumulates during extended integration periods. The result is a high performance video imaging camera with low noise, wide dynamic range, low-light capability, and spectral response to near IR.

Design and construction of the cooled camera module lowers the sensor temperature to reduce dark current noise that accumulates during extended integration periods. The sensor operates at 5° C in a 25° C ambient environment, resulting in a reduction of dark current to about one-eighth that without cooling. Using a Peltier cooler, along with a natural convection, dual-section heat sink, the sensor is able to collect more light to display as a reduced noise video image.

Aplogies for the late follow-up.

Thanks guys for the brief tutorial. Based on your comments, we have decided to not get a cooled CCD. Namely because it is only handy for very long expsoures i.e greater than 60 secs. Since most of our exposures for fluorescence is less than that, its a waste of $$$.

Out of interest the cooling system was a peltier system. It can reach down to about 5 degree celcius.