Scripted Preprocessing - Bias

[Forum_2017]

Hi,

The window 'BIAS' for a bias frame is not able to be scripted. However, if you are only using a bias frame with no darks in the preprocessing script is this the same?

sub AddL(line$)
pre$ = pre$ + line$ + crlf$
end sub

AddL("#PREPROCESSING")
AddL("Dark=" + yourdir$ + "Bias\MBA2.fit")
AddL("Image=" + yourdir$ + name$+"\FG"+N$+".fit")
AddL("Flat=" + yourdir$ + "Flats\MFG2" + ".fit")
AddL("ExtraFilters=1")
AddL("AlignMethod=2")
AddL("CombineMethod=3")
For l = 1 to count(pre$)
print pre${l}
Next l
Preprocessing(pre$)

Regards,
John

[Forum_2017]

Yes.

Nowadays "using Bias" has two different meanings, both "improper":

1) Using a Bias AS A DARK FRAME, this means that if your camera has very little dark current then you may use a (master) dark frame taken with an exposure of zero seconds, and at a random temperature. Actually this means that you are using an "approximate dark frame".

2) Using a Bias for the SCALED DARK FRAME tecnique. This was the original meaning, and it's a rare tecnique nowadays. In Preprocessing you must use the boxes "Scaled dark frames - bias". This cannot be scripted.

Any other use is wrong. Don't use Biases if not needed. About point (1) I suggest to use a real dark frame even if your camera has low noise.

[Forum_2017]

Ok thanks..
I was sure this was the case.
Thanks Fabio.
J