SharpCap Forums

Hi Brian Where did the eyebrow raise come from? My process is almost exactly the same as yours but where you say 2 seconds I used to use 1.35s and now I use 8. A slight difference is that I aim for a mean pixel value between 20,000 and 25,000 ADU because nonlinearity starts to kick in higher than th...

Just finished some more flats today using an iPad screen as a light source. I've always done flats at 1.35s exposure (to match darks at that exposure). Today with the room temperature at 13 degrees the camera at 100% cooling settled at -17 degrees. I decreased the screen brightness so that the requi...

I see that it is coming up to nearly two years since my initial post. Guess what - it took me that long to realise what the problem is. Turns out that (I suspect) light falling on the sensor warms up the sensor. That's why when I cool the camera to -20 then turn on the light source for flats the cam...

Um, that's not quite right. I was asking about dynamic range of a stack, not SNR. Did you mean Stack DR = number of subs * sub FWD / stack noise (in electrons) or Stack DR = number of subs * sub FWD / stack read noise (in electrons) I used the second formula and the results of the sensor analysis fo...

frame dynamic range vs stack dynamic range (glover).png This chart is extremely interesting, Robin. It seems that if you are stacking then you should consider the stack dynamic range instead of the frame dynamic range. In this situation (which applies to my camera) I would be tempted to go with gai...

Fine night last night but pretty warm at 20 degrees. SGP cooled the camera down to -20 (40 below ambient - better than the spec of 35) using 100% cooler power. I did a focus run then kicked off a sequence. But SGP warned about the temperature which had warmed to -13, still using 100% cooler power. I...

It's too hot here now to do any more tests - the camera only goes 35 degrees below ambient (I have managed 38). But when I tested the ASCOM driver I saw two things: The ASCOM cooler power ranged from 0 to 100 The temperature was much lower than using the direct driver - that may be due to the reduce...

Another problem - maybe related or maybe not - is that when I do a sensor analysis (at -12 degrees) it aborts with a message "minimum exposure reached." The exposure shown is 1.74ms but this camera can go way below that - it can go down to 0.001ms. I suspect that SharpCap and the QHY drive...

No, it's definitely a bug somewhere. I can set the camera to 60s exposure in both SharpCap and SGP and only SGP can cool the camera to -20.

Why is SharpCap allowing a value of 255 for the percentage? If 255% is OK then perhaps 512% is OK too. Maybe that will fix the problem.

Since you asked - with a QHY600C-PH and 800x600 and USB Traffic 0 I'm getting 0.5fps.

My problem is that I'm only getting partial cooling - I have started a topic for this.