Quote:
Originally Posted by Martin Pugh
I thought there was significantly more signal in the 2x2 image actually, but much more noise too.
Not seeing big halos, but I am trying to track down some other weirdness, which I think is down to residual tilt. The black streaks that you can see in other images certainly appear with the 600C attached to the Sigma lens. I think they are caused by the cables coming off the camera/FW etc as they are obviously front mounted. But I take care of that in a different way.
No banding.
You really have to study the graphs on the QHY website to fully understand what the 3 different readout modes offer. I am yet decided on whether I should just settle on one mode/value.
Naming convention of darks and biases is critical as I build my library across the different readout modes.
One thing I just cannot get my head around is the offset......I just cannot figure out how to use it or what it does so it is set to a single value across all readmodes at present. Even the document written by Dr Q about setting that value makes no sense.
One thing I have found useful though is using the camera with SharpCap. I have been experimenting on adjusting read out modes and gain values whilst using a bahtinov mask. Back to that offset.....adjusting that real time under Sharpcap appears to have no impact at all.
Martin
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The extra noise in 2x2 would be from the extra readouts. I think the CMOS sensors need to do 4 readouts to get 2x2 so you get 4X read noise (perhaps its 2X, but I think its 4X). Apparently you get the same result by software binning the 1x1 data.
My understanding of offset is its like setting a black point. Too high and you clip the blacks, too low and it doesn't cut off noise.
I can see naming would be very important as I have lost some images in the past due to mixing the download speeds from the FLI cameras.
Overall the camera looks very promising and sensitive and quite flexible.
1x1 would suit FSQ style scopes or lenses and 2x2 would suit longer focal lengths I assume.
Tilt would be tough at F2.2. Does it get confused sometimes with collimation? It may look similar perhaps in some cases.
Greg.