SharpCap Forums

Hi,
Im new to colour imaging. There are more setting in SharpCap than i was prepared for.

Colour Space RAW8, RAW16, RGB24. Ive set this to RAW16. Some of my first efforts were at RGB24 but there is warning about bit depth.
Hardware BInning on: Binning 1x1 2x2, Ive set this to 1x1. Does 2x2 work ?
Hardware BInning off: Binning 1x1 2x2,...8x8 When should these be used?
Debayer Preview. Ive set this to On
Analogue Gain. Ive set this to 256, or the value shown by the Sensor Analysis
Auto Exp Target. What is this? Ive not changed it. Its set to 120.
Auto Gain with Auto Exposure OFF. What does this do?
Black Level. I understand this. Ive set it to 40. It may need to be changed.
Exposure/Gain Shift. Slider control. This is set to 0. What is it used for ?

Image control Bal R Bal G, Bal B. OK I can see this would be useful. How do I judge the values ? Is it a constant for the camera, or should i expect to change them?

Many thanks for sage advice. Some setting other images are using would be very helpful to get me going

Tim
(Abingdon)

Hi Tim,

RAW16 is normal for deep sky, RAW8 for lunar or planetary. RGB24 is more suitable for terrestrial imaging (using the camera as an expensive webcam).

Binning works as you would expect, but for CMOS cameras is done as a digital operation, so often it averages pixel values (reducing noise levels) rather than adding them (increasing brightness). If you choose 'Hardware Binning on' then the binning is done on the camera, which has the advantage of reducing the amount of data that needs to be transferred back to the PC - in some cases like Lunar/Solar imaging this might be helpful. 1x1 binning means 'no binning'.

You can ignore the 'auto exp'/'auto gain' stuff - those give you fine control over how the auto exposure mode works if you select auto exposure. If you keep the exposure set manually then those are not important.

Exposure/Gain Shift is a composite control that allows you to adjust the balance between exposure and gain without altering the image brightness - move it to the left to reduce exposure and increase gain, to the right to increase exposure and reduce gain. It's quite handy to switch between 'focus/framing' settings with high gain and shorter exposures and actual deep sky imaging settings with longer exposures and lower gain.

White balance controls - my advice is do not touch, leave at defaults and fix white balance in the processing stage.

As to setting the gain, that's the complex part with a CMOS camera (particularly one where the sensor has a switch between LCG and HCG modes, like the IMX585). Changing the gain changes the read noise of the sensor, which in turn affects the length of exposure you need to use. In some cases it may be worth going to a gain of 1365 or above, which pushes the Altair 585 into HCG mode in SharpCap, but that may be too much in other situations due to the reduced full well depth. Using the 'Smart Histogram Brain Window' will work out the best gain for your setup - see https://docs.sharpcap.co.uk/4.1/#The%20 ... n%20Window

cheers,

Robin