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Single Frame 33.8 deg from Target Warning Adding Observations
#1
Hi Greg,

ST4 4.0d

While importing a FITS image as a new observation to an imaging project, the import dialog shows a warning that the frame is significantly away from the target:
   

The target is NGC 3718, at 11 33 38.6,  +52 57 46.

The FITS header for the image shows OBJCTRA = 11 32 46.317, OBJCTDEC = 53 15 01.64:
   

While it's just a warning, it seems like something is not correct.  The import dialog also said there was no Location or Imaging System specified in the header.  The FITS header shows the location's SITELAT and SITELONG correctly.

Maybe this is caused by ST4 expecting different FITS header keywords?  The image was acquired with TheSkyX's camera add-on.

Thanks,
Rowland
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#2
Hello,

It looks like the image was centered away from the location of the target. Hard to say if it is accurate or not, but you can ignore that warning. I'll look into the location. FITS is a standard, but its been around so long that modifications and extensions have crept in.
Clear skies,
Greg

SkyTools Developer
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#3
Thanks Greg. Yes, I used the composition panel of the project dialog to adjust the center of the image, but less than a degree, definitely not 33 degrees.
I do ignore this warning but I get it on most of my observations so figured you would want to check it out.

Thanks again,
Rowland
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#4
Please email me one of the FITS images that is giving you this error. I don't see any obvious problems with the key words, but I need to see the actual headers to understand the problem.

BTW I believe you sent me an image last fall that was also not working, but when I checked it didn't have a valid FITS header. I think that was just an isolated problem with that image.
Clear skies,
Greg

SkyTools Developer
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#5
What I discovered is that:

1. None of your locations set up in SkyTools are apparently within 1000 meters of the site location in the FITS header. You should check your location to be sure
that is set correctly in both SkyTools and the camera.

2. There is a bug in the code that reads the RA/Dec for the image that only happens when the RA and DEC keywords are not present, which causes it to not check the OBJCTRA and OBJCTDEC key words. I;ll have a fix for this.

The good news is that neither of these things really matter. The warnings are there to alert you to possible mismatches between what SkyTools is expecting and what is wriotten in the header, but this header info is actually used in this case, so you can safely ignore it.
Clear skies,
Greg

SkyTools Developer
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#6
Hi Greg,

Good catch on the latitude / longitude. Looks like I made a mistake and typed the latitude as 36:56:56 in my location instead of 35:56:56. I'll fix that in ST4.

I realize it's just a warning, so no worries.

So the "No location specified in header" warning means "the coordinates of the location in the header are more than 1000 meters away from any location defined in ST4." That's a good bit of trivia to know Smile .

Thanks for looking into this.

Cheers,
Rowland
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#7
(2019-03-30, 10:14 AM)Rowland Wrote: Hi Greg,

Good catch on the latitude / longitude.  Looks like I made a mistake and typed the latitude as 36:56:56 in my location instead of 35:56:56.   I'll fix that in ST4.

I realize it's just a warning, so no worries.  

So the "No location specified in header" warning means "the coordinates of the location in the header are more than 1000 meters away from any location defined in ST4."  That's a good bit of trivia to know Smile .

Thanks for looking into this.  

Cheers,
Rowland

I'll fix that too. It appears that the error message failed to evolve along with the rest of the code.
Clear skies,
Greg

SkyTools Developer
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#8
Hi Greg,

I am getting a similar set of messages for observation import re the FITS header not containing information that would appear to be present (Filter and Image Type). I'm running ST4.0e.

The ST4 messages are;

No location specified in header
Imaging System: EQMOD ASCOM HEQ5/6 (project: 120ED Refractor ZWO 1600 Pro)
No filter specified in header
Binning: 2x2

Start: 2020 January 3 11:46:19 UT
Exposure time: 43 sec

Single frame 115.1 degrees from target  *** Error? ***

WARNING: not of image type light!
--------------------------------------------------------------------------------------------------------
The FITS Header is;

Filename IC434 HorseHead_Light_43sec_2020-01-03_0043_Blue_frame1.fit
SIMPLE 0
BITPIX 16
NAXIS 2
NAXIS1 2328
NAXIS2 1760
BZERO 32768
BSCALE 1
CRPIX1 1164
CRPIX2 880
CTYPE1 RA---TAN
CTYPE2 DEC--TAN
OBJECT IC434 HorseHead
DATE-LOC 2020-01-03T22:46:19
DATE-OBS 2020-01-03T11:46:19
IMAGETYP LIGHT 
CREATOR Sequence Generator Pro v3.1.0.423
INSTRUME ZWO ASI1600MM Pro
FOCUSER FocusLynx Focuser 1
FOCPOS 60310
FOCTEMP 24.62666667
FWHEEL ZWO FilterWheel 1
FILTER Blue   
EXPOSURE 43
CCD-TEMP -15
SET-TEMP -15
XBINNING 2
CCDXBIN 2
YBINNING 2
CCDYBIN 2
TELESCOP EQMOD ASCOM HEQ5/6
RA 85.36581694
DEC -2.14915513
CRVAL1 85.36581694
CRVAL2 -2.14915513
OBJCTRA 05 41 27.796
OBJCTDEC -02 08 56.958
AIRMASS 1.196990403
OBJCTALT 56.70907086
CENTALT 56.70907086
FOCALLEN 840
FLIPPED 0
ANGLE 307.23
SCALE 1.72442
PIXSCALE 1.72442
POSANGLE 307.230011
GAIN 139
EGAIN 4.960000038
OFFSET 21

I'll check my lat/long to see if it is within the 1000 metre radius.
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#9
Hi,

Dumb question, but that's always the best place to start: Is there a Filter defined for this imaging system in SkyTools that is called "Blue?".

I have never seen the image type error before. That's perplexing. If you can, please email me the image at support at skyhound.com.

Thanks
Clear skies,
Greg

SkyTools Developer
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#10
(2020-01-03, 08:56 PM)theskyhound Wrote: Hi,

Dumb question, but that's always the best place to start: Is there a Filter defined for this imaging system in SkyTools that is called "Blue?".

I have never seen the image type error before. That's perplexing. If you can, please email me the image at support at skyhound.com.

Thanks

That's never a dumb question as you have sparked my thinking.

Two things have come to mind.
1) In ST4 I call them "ZWO Blue" but in SGP they are called "Blue". Are these to be defined with the same names???
2) When I did a raw extract of the FITS header I actually get the FILTER as 'Blue    ' and IMAGETYP as 'LIGHT   '

Could this be the issue?

David
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