Integrating images with different temperatures

Colin Clackson

I have an interesting dilemma. Last night my camera temperature dropped to -13C because of the ambient temperature. Ordinarily my camera is set to -10C. Now I'm having trouble integrating the -13C light frames with the -10C light frames. WBPP appears to choke on dark frames at -10C calibrating the -13C light frames and visa versa. Creating one master dark file of both the -10C and -13C frames together didn't work either. My workaround is to run the images through WBPP separately, then take all of the registered light frames and run them through the star alignment process and then take those images and run them through the image integration process.

Can you think of a more elegant solution?

Colin

BlockHead

Hmmm.. I am not certain I understand the source of the problem but I do know the solution.

WBPP is agnostic about temperature. It does not match temperatures of darks and lights on its own. You would have to use grouping keywords to distinguish them. But you only have ONE set of darks with two temperatures. That is OK. Typically 5C differential is considered significant. You are less than that.

So if you wanted to.. you can configure WBPP to calibrate all of your lights with a single master dark frame at -10. You would use the dangerous dark optimization option. This is what it is designed for. It will scale the dark to better subtract from your lights that were taken at -13C. It will not be perfect because some over-subtraction of hot pixels might happen... but if your data is dithered and you have many frames this will not be an issue.

Now none of this should cause WBPP to "choke" and not calibrate the -13C lights with the -10C darks. This might be pointing at a different issue.

-the Blockhead

Colin Clackson

Umm.... nevermind. Not sure what I did differently but this time WBP processed all the images together. Go figure.