CometAlignment - Can't convert DATE-OBS keyword value to a Julian day number

[christian_sp]

Hi,

After installing 1.8.5 I started to use CometAlignment. I tried to add my calibrated images (DSLR Canon 1000D) and received the error message

"Can't convert DATE-OBS keyword value '2017-05-17T22:34:27Z' to a Julian day number".

After an idea from another user, I changed the DATE-OBS keyword and tried to use the date without the letter Z at the end.
And it worked.

Any idea? Before 1.8.5, I could add the images without problems. My fault in the workflow, a change in 1.8.5 or a bug ?

best regards
Christian

[Juan Conejero]

Hi Christian,

DATE-OBS should not have a time zone indicator, e.g. the trailing 'Z' (meaning Zulu time, or UTC). If one of our tools has generated this keyword, then this is a bug. How have you produced the image file? Is it an XISF file?

[christian_sp]

When I open a raw-image from my DSLR directly via PixInsight, the timestamp already shows the time indicator. I have included a screenshot of the fitsheader.

I am processing all the raw files directly in Pixinsight, without any other tool before.
After calibration-process they are converted to XISF and the rest of my workflow I am working with XISF file.

best regards
Christian





Process Console after loading raw-image:

open "C:/Users/Sandra&Christian/Documents/Astronomie/2016-08-01 Barnard 142-143 Altair 4x600s iso200 50mm/IMG_6764.CR2"
Reading 1 file(s):
C:/Users/SandraChristian/Documents/Astronomie/2016-08-01 Barnard 142-143 Altair 4x600s iso200 50mm/IMG_6764.CR2

Timestamp: Mon Aug  1 22:37:58 2016
Camera: Canon EOS 1000D
ISO speed: 200
Shutter: 598.0 sec
Aperture: f/4.0
Focal length: 50.0 mm
Embedded ICC profile: no
Number of raw images: 1
Thumb size:  1936 x 1288
Full size:   3948 x 2622
Image size:  3906 x 2602
Output size: 3906 x 2602
Raw colors: 3
Filter pattern: RG/GB
Daylight multipliers: 2.362489 0.919100 1.182562
Camera multipliers: 1858.000000 1120.000000 2133.000000 1120.000000

Invoking: dcraw -4 -o 0 -r 1 1 1 1 -D -t 0 -k 0 -H 1
Decoding Canon EOS 1000D file (3906x2602 pixels, ISO=200, Exposure=598.00s): done
Loading raw image: done

[christian_sp]

I tried different images, to be shure that the problem isn´t on specific images, but all have the time indicator.
I can provide some images for testing, if it is useful.

[Juan Conejero]

Bug confirmed. The DSLR_RAW module generates DATE_OBS FITS keywords in ISO 8601 format with a zulu time zone indicator. The FITS standard does not allow time zones, so this is incorrect.

I'll release an update to the DSLR_RAW module tomorrow morning. Thank you for discovering this issue, and sorry for the inconvenience.

[christian_sp]

thank you for the support 

[Juan Conejero]

This bug is now fixed with an update to the DSLR_RAW module I've just released. Thank you for your support.