As several APP users have noticed, there is currently a nasty bug in flat-field calibration.
This causes the vignetting profile in the calibrated light to look over-corrected, (instead of fully-corrected), due to a problem in the normalization of the flats before integrating the flats into the masterflat.
This bug was introduced by a change in APP's normalization engine and I have located the problem and thus fixed it now.
An example of the bug is described here extensively by Kirk @1cm69 (for which many thanks 😉 ):
For this latest attempt I am using data from the folder - NIKON_D800 > 2016 > 20161106
and as specified in the LOG for this data I am using NEF files:
6111 - 6122 for BIAS ISO800 1/8000s
6281 - 6312 for FLAT ISO ISO800 1/20s
6323 - 6334 for Dark ISO800 180s
6262 - 6271 for LIGHT ISO800 180s
This is how I process:
Load F & D to create BPM (this also creates MF & MD which I delete) then clear the load
load F, B & BPM to create MF - then clear the load
Load D to create MD - then clear load
Load L, BPM, MF & MD and hit Calibrate
At this stage I took a screenshot of the Linear data & also the Calibrated data:
You can easily see the vignette in the Linear data but this should disappear in the Calibrated data but it doesn't, it just changes colour.
So what is going on??
I am currently working on a big upgrade of the entire calibration engine and I am making really good progress, so once APP 1.060 is released, this bug shall be fixed and calibration will also become a lot easier in APP.
(I have also removed the very strict calibration requirements on ISO/gain and exposure values for bias, darks and dark flats.)
Ik heb ook een aantal datasets die compleet fout gaan en anderen ( veel ) die goed gaan!! Dit begrijp ik niet goed mar ik hoop dat er binnenkort de nieuwe versie aankomt! Beste groeten, Mert
Translation by Mabula :
Dear Mabula,
Is there a timeframe for the fix?
Some datasets go fine, where others are not ;-( which is odd... I am anxious for the new version !!
My Master D/F are pre-made for each iso, expo and separated for each camera model Im using. and follow the instructions how to made them. Now I noticed they coming out with a different pixel size than the subs.
The APP told me that these M-F/D is not same size as the subs and will not be used in the process.
Running my first analysis now. 220 frames to analyze across 2 nights. Should be a good first test. First impression, the file loading changes and groupings are excellent. Second, the star analysis was done in record time, even for that many frames to look at. So far, so good. Thanks for the great update!
