No data in fits header after integration

[pluckas]

Hello,

I am sure I am doing something wrong, but when I integrate a number of fits files, the resultant image has no information at all in the fits header.

Is this normal for PixInsight, or have I forgotten a check box somewhere in the process.

Thanks,

Paul

[Juan Conejero]

Hi Paul,

This is by design. Once you have integrated a set of images, it makes no sense to copy all the FITS headers in PixInsight because we have much more versatile and powerful resources:

- The instance of ImageIntegration is available in the processing history of the integrated image. You can use the History Explorer window to see it as its initial state. This instance contains all the information about the source images, integration parameters (image weighting criteria, rejection parameters, etc.) and all the statistics of the process (rejected pixels, noise estimates, SNR improvements).

- You can create a process icon with the ImageIntegration instance used, which transports all the information described above. This icon can be saved as an XML file (XPSM format).

- You can save a project to store the state of the whole PixInsight platform when you integrated the images.

[pluckas]

Thanks for your reply Juan. This does make sense, though I was using PixInsight in a slightly unusual way - creating a master image from sub exposures in order to perform some photometry in another application which requires data from the fits header.  It would have been nice to do this as I have been enjoying the fact that PixInsight allows me to work exclusively outside of Windows (well, almost).  ;-)

[RBA]

This is by design. Once you have integrated a set of images, it makes no sense to copy all the FITS headers in PixInsight because we have much more versatile and powerful resources:

It may make sense to copy some of them though, perhaps at least those headers that are common to all the files being integrated (I say this not knowing whether that's being done).

[Geoff]

It may make sense to copy some of them though, perhaps at least those headers that are common to all the files being integrated (I say this not knowing whether that's being done).

I think this is true.  if I have an integrated file and wish to check what telescope was used, who the observer was, place of observation, etc etc, the only way i can do it (apart from having memorised the details) is to use the history to find out which frames were integrated, then track down one of these and inspect its fits file.  This seems to be a very roundabout way to do this.
Geoff

[mschuster]

I am thinking of a script that reads processing history, discovers fits headers and merges and applies them according to user criteria. But I don't see anything in the script API's that lets a script obtain history. Maybe I missed it. Is this possible?

[Juan Conejero]

The next versions of the StarAlignment and ImageIntegration tools will include the entire FITS headers of all processed images. This is a long time requested feature, already in the to-do list.

I don't see anything in the script API's that lets a script obtain history. Maybe I missed it. Is this possible?

Yes. The properties you're looking for are:

ProcessContainer View.processing

This is a ProcessContainer object with the entire processing of a view. The ProcessContainer object is rather straightforward: it is essentially a list of ProcessInstance objects. ProcessContainer is itself a derived object of ProcessInstance, so the entire thing is recursive.

ProcessContainer View.initialProcessing

Similar to View.processing, but this one stores the initial set of processes that led to the view in its initial state. Usually an empty ProcessContainer.

uint View.historyIndex

An integer >= 0 that points to the current view state. With undo/redo operations the history index of a view can be decreased/increased, respectively.

let me know if you need more information.

[troypiggo]

Glad I read this thread.  I've been wondering the same thing.  Would be handy to have total integration times, ie a sum of the sub lengths.  Maybe they can be 2 different headers:

Exposure: 180mins
Sub length: 20mins
No of subs: 9

or just

Exposure: 9x20mins

And can the FITS headers, or at least some of them, be exported into EXIF information for JPG/TIFF files etc?