Hi Dennis,Dennis wrote: ↑Mon May 29, 2023 7:11 pmrsfoto wrote: ↑Mon May 29, 2023 3:28 pmHi Dennis,
Be aware of one thing and that is the humidity in the air.
Cooling directly the chip always implies a danger of condensation and freezing of the chip. Cooling the air around the chip will not achieve the same cooling as a direct cooling but it will cool the chip without danger of condensation or freezing the chip.
Now we have to differentiate why we cool our DSO cameras and why we cool out Sun imaging cameras.
We cool our DSO cameras in order to bring down noise due to long exposure times eg. 5, 10 or even more minutes.
We cool our Sun imaging cameras in order to increase the life of the electronic components. With exposure times of 50 milliseconds (these are my max exposure times) or less we have no noise in the images.
The noise we have or allegedly see, is because we introduce it ourselves with the famous Wavelet sharpening trying to get very sharp details or we crank up the gain just in order to get very short exposures (I always leave gain at 0 and bite the bullet with exposures times of about 45 - 50ms)... but we forget that the details we want to image are by far more affected by hot air turbulence be it in the sky or in our telescopes ...
About exposure times very few people ever made a series of tests in order to see when an exposure time is to high and prefer to crank up GAIN.
Einstein said: " If you do what others say, you will never know what you are really doing" (FAKE quote, I just invented it. Einstein never said that )
IMHO
Hi Rainer,
a good quote, i like it.
About condensation: that sure is a thing with the peltier coolers on the deep sky cameras in night time conditions.
But in warm weather in daytime with a air blower cooling?
On my cpu in the pc i also put a strong air cooler, never had condensation though. The rel. air humidity is not high enough under these conditions.
You can not compare a strong air cooling and placing a TEC directly on the back of a imaging chip or even let me say a TEC directly onto a Processor and having it enclosed in a casing with a lot of holes ... like a PC casing. Look at Martin_S's posting where he showed an image of the TEC and Fan doing a dry run. He got a lot of ice on the parts ... Martin_S lives in Australia
The higher the temperature the higher the amount of water in the air but you already know that. You can not compare the comfortable temperatures of Germany with our temperatures in Mexico or Australia. At the moment I am writing this we have here at my place 31°C and the forecast for Thursday is 34°C ... 50% of the las 3 weeks we have had days with more then 32°C.
https://www.fstweb.de/de/wissen-tools/d ... cktabelle/
IMHO