Hi guys,
I'm doing spectroscopy with Ekos for a month now.
I need some improvments to do thing well and control better my exposition time
First : in fits viewer (in single frame or in ekos), when I use fits viewer, histogram tool... I found a Bug
I found that "MAX" displayed in stat is not 'pixel' max value but 'scale' max value. (scale that can be changed in histogram view)
So, this is not STATS... NB : it's the same for MIN value : it's the minimum of visualisation, not minimum Value.
(I get a eye on code... And it seems code call "DATAMAX/DATAMIN" fits keywords...
Specification of FITS standard says :
KEYWORD: DATAMAX
REFERENCE: FITS Standard
STATUS: reserved
HDU: image
VALUE: real
COMMENT: maximum data value
DEFINITION: The value field shall always contain a floating point
number, regardless of the value of BITPIX. This number shall give the
maximum valid physical value represented by the array, exclusive of any
special values.
SO... I don't think we can use it to store visualisation things as it represents the dynamic of picture.
-> let's create a SPECIAL KSTARS keyword, no ? (Something like : VISUMAX et VISUMIN...)
So, by consequence, statistics about MIN and MAX... are... fake (sorry for my poor english here...). It needs a calculation somewhere (at load ?)
In my use, I need to know which part of spectrum is overexposed. Statistics helps... but it could exist noisy/dark pixels that give a false sensation of overexposition... So I need something like:
-> A button that makes blink all pixels equals or higher ( ?) than the cam's deep or a human entry should be a solution (the better for me, as in DSLR) (first seconds of this video
)
-> Or a selection, then a right click to give stats (real one
) of this crop can be usable too.
Thanks guy.
JB