HistogrammTransfrmation produce error

[drknoppi]

Hello ,
I am Rainer and i try to start working with PI , but  if i tried to streched a linear lum-image to nonlinear and after i choosed the right image
in HT , a violent exception occured I don`t know whats wrong here .
I hope you have  a good idea .

See attachment

Best regards
Rainer

[georg.viehoever]

Is that repeatable? Which OS? Anything special in your image? Can you share your image file (e.g. dropbox)?
Georg

[drknoppi]

Hello Georg,

yes its repeatable also with non - linear images  , i work under MAC OS X 10.8.4, 8 Gbyte RAM/ 512 SSD.
It seems to be an error while selecting/reading an  image in HistogrammTransformation version PI  -   1.8 .
Best regards and thank you for the quick answer .
Rainer

[georg.viehoever]

Never saw that on Win7 or Linux. Maybe MacOS specific, or specific for your image.
Georg

[pfile]

if you still have it open, i would save the project, quit PI and then reload the project. after an issue like this PI can sometimes just completely crash and you can lose all your work (unless you want to go through the pain of trying to restore your .swp file)

[drknoppi]

Hello Georg,
after saving all important files. i reconstruct the complete project,
i found that my Lum file from the old project was wrong, that
why pi crashed every time while i  used histrogrammtransormation 
Thanks for your help
Rainer

[pfile]

so it is a corrupt .fits file? maybe you can send it to juan - it's kind of a bad thing when a program crashes due to file parsing issues.

[drknoppi]

Hello,
 i tried again to load lum and h - alpha image
inside a new ! project . And no problems select and show images
within histogrammtransormation  The problem must be inside the old project ?? but not inside the image !
I am lucky within the new project i can`t find any problems, but what was the reason ?

I found another problem after loading  f.e. red calibrated image in a new project
and after STF automatic i found wave like image structures, why ?
Best regards
Rainer

[Carlos Milovic]

This could be a problem of posterization. First thing to try, is to copy the STF to an HistogramTransformation, apply it to the image, and see if the "waves" are there. If not, it was a problem of the STF's limited dynamic range.
If the problem continues, then it may be a problem in the calibration/processing... so, we should know which steps did you follow.

[edd]

Looks like CCD fringing to me, which would need the construction of a superflat to remove?

[Conor]

Looks like the kind of artifacts you'd see applying a stretch to a lossy format, like JFIF, to me.

Can you upload example data somewhere?