SharpCap Forums

Robin, a couple of questions about these feature;-
1) for sensor analysis, do i need to use the full image train - or can I just plug my camera(s) into my office PC and do the analysis there - if so - is there a way to copy the results to my imaging laptop for use with Smart histo?
2) I'm guessing that Smart Histogram & the Brain need to use the full image train and results would vary depending on image train and the real sky conditions, so is something that should/could be done at start of imaging session and maybe during also if sky conditions change?.
3) Does the sensor analysis depend on camera temperature? If so - is there a way of building a library of sensor analyses?

Thanks
Neil

Hi Neil,

1) you can perform the analysis on your desktop with the sensor exposed if you want (although the light levels might be a bit bright for that). No need for the imaging train, just an even area of steady illumination. The files get saved into %APPDATA%\SharpCap\SensorCharacteristics (ie C:\Users\robin\AppData\Roaming\SharpCap\SensorCharacteristics) and can be copied to another machine. In due course I intend to ship a wide range of sensor measurements with SharpCap.

2) To use the full power of the brain you do need your imaging train so that it can measure the real sky background brightness, so as you say, measure at the start of a session and repeat if conditions change (ie imaging nearer to/further from the moon)

3) The sensor measurements taken do not change significantly with temperature, so no need to worry about that side of things. What does change with temperature is thermal noise, but actually that gets measured as part of the sky brightness - ie the brightness measured is (light pollution + thermal noise) in e/pixel/second.

hope this helps,

Robin

PS - do remember to measure your sensor in both 8 bit and 12/16 bit mode for the best results.

That's great, thanks. I'll lower the light levels with a t-shirt- a-la a flat frame

Now I can get my ASI224 and ASI 1600 sorted while its going to be cloudy.

Neil

This post answered all of the question I had for the sensor analysis except one:

Does the BIN setting matter?

Hi,

Binning is interesting here - you must not use binning when measuring the sensor as it throws off the analysis (actually the latest builds should stop you from making this mistake).

If your camera averages when binning (ie the image does not get brighter when you go from 1x1 to 2x2) then the smart histogram will give you correct results.

If your camera adds pixel values when binning (ie the image gets brighter when you switch from 1x1 to 2x2) then you will currently get incorrect results. I will need to factor this in to the calculation (will add this to a beta build soon).

thanks for pointing this out!

Robin