I was told that I could make darks the next day by capping my ZWO294 MC Pro using the same exposure, gain, and temperature. A friend just told me that even thought the temperature reads -18C when imaging, that doesn’t mean the camera is at -18C, it means that it’s -18 degrees below ambient temperature. So, if I were to set up darks the next day and cool the camera to -18, it wouldn’t be the same. He says I “have to” get darks when I capture my lights.
Wondering if he’s right?
Thank you ,
Joe
Taking darks the next day question
Re: Taking darks the next day question
https://www.cloudynights.com/topic/5686 ... confusion/
Perhaps they say below ambient because the cooler can't keep up when it's really hot out or it's worded wrong via translation. Whatever the reason, -15 at night will be the same the next day. Everyone uses a "dark library" to save time. Taking darks every night would waste too much time.
I take all my images at -15 to simplify my dark library....for my camera the curve gets pretty flat around -15 so there isn't much reason to go cooler. This makes all my files easier to manage.......hope that heps.
Perhaps they say below ambient because the cooler can't keep up when it's really hot out or it's worded wrong via translation. Whatever the reason, -15 at night will be the same the next day. Everyone uses a "dark library" to save time. Taking darks every night would waste too much time.
I take all my images at -15 to simplify my dark library....for my camera the curve gets pretty flat around -15 so there isn't much reason to go cooler. This makes all my files easier to manage.......hope that heps.
Re: Taking darks the next day question
Much thanks Chongo228, great idea to make a library with -15C darks. I’ll be doing this from now on.
Joe
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Re: Taking darks the next day question
Hi,
Yes the temperature readout that you see in SharpCap and other software is the true temperature of the sensor, not some sort of offset from ambient. So if you set the temperature to -15 then the sensor will be at (roughly) the same temperature regardless of whether you do it during the day or during the night.
I do say roughly because the temperature sensor in the camera measures the temperature at a single point. Maybe that's just to the side of the sensor. Now imagine that you set a -15 target at night when the ambient temperature is zero and then later you set the same target during the day when the ambient temperature is 20° C. The temperature at the thermal sensor point will honestly be the same in both cases, but the temperature of other things in and around the camera sensor area may differ slightly. Whether this is a big enough effect to worry about, I have no idea!
Cheers, Robin
Yes the temperature readout that you see in SharpCap and other software is the true temperature of the sensor, not some sort of offset from ambient. So if you set the temperature to -15 then the sensor will be at (roughly) the same temperature regardless of whether you do it during the day or during the night.
I do say roughly because the temperature sensor in the camera measures the temperature at a single point. Maybe that's just to the side of the sensor. Now imagine that you set a -15 target at night when the ambient temperature is zero and then later you set the same target during the day when the ambient temperature is 20° C. The temperature at the thermal sensor point will honestly be the same in both cases, but the temperature of other things in and around the camera sensor area may differ slightly. Whether this is a big enough effect to worry about, I have no idea!
Cheers, Robin