SharpCap Forums

Hi,

I tried connecting Player One Poseidon-C Pro camera in the SC program.
The camera has a resolution of 6252x4176, but in 2x2 binning mode the camera resolution is 3124x2088 instead of 3126x2088. Similar situation in 4x4 binning mode - instead of 1563x1044 resolution 1560x1044 is used. Why can't the “correct” resolutions be used?
When I use the camera with TheSkyX (ASCOM driver) binning image has resolution 3126x2088 and 1563x1044

Alex

Hi,

all cameras have rules about the values that can be used for the width and height of the image, and according to the documentation for the PlayerOne cameras, they require the width to be a multiple of 4 and the height to be a multiple of 2. SharpCap applies those rules, leading to the slightly altered sizes that you see (sending an invalid size to the camera usually results in an error leading to no images at all).

It sounds like there might be some more complex exceptions to those rules - perhaps regarding to binning or when the area is equal to the maximum possible area, but I cannot find any documentation that mentions this sort of thing. I tend to be rather cautious about changing this sort of thing as I tried something similar once for ZWO cameras and found that what worked nicely for one model didn't work for other models

Do you have something that actually breaks because of the slightly different resolution, or is it just that it would be nice if it was all the same?

cheers,

Robin

As far as I understand the problem is probably driver related. I tried connecting the camera in NINA. There you can use either ASCOM driver or native driver. In the first case when binning 2x2 images have size 3126x2088, and in the second case 3124x2088. The problem with the image size occurred when trying to calibrate the received images. The images themselves were obtained in TheSkyX (ASCOM). Dark images were acquired in SharpCap.
Of course the problem is solved by using the same software. But it was not clear why different drivers give different resolutions.

Alex

Hi Alex,

thanks for the update - it sounds like software using the SDK to access the camera directly is working like SharpCap does with the slightly lower resolution - it's probably applying the same rules that SharpCap is to arrive at that resolution. Since the ASCOM driver is written by PlayerOne themselves, they presumably know exactly when the rules about resolution don't apply and take advantage of that, leading to the slightly different resolution.

I'm probably going to stick with the current situation (unless some very good reason comes up to change). At the moment, you get problems if you have used a mix of ASCOM and SharpCap to capture the images. If I were to change then you would end up with a problem if you had used old version of SharpCap and new version of SharpCap - which I think would probably affect more people.

cheers,

Robin