NINA files saved as XISF or FITs?

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Richard Payne avatar
How many NINA users save files as XISF versus FITs?
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Quinn Groessl avatar
I switched to XISF recently. I figure I'm using Pixinsight anyway. However since I changed it it's been cloudy, so I might change it back.
Charles Hagen avatar
I personally save as XISF with LZ4 compression - its lossless compression and it reduces the size on disk a fair amount. it also means that they will transfer from the observatory faster which is a nice perk. Both file formats are totally appropriate, the only downside of course is that if in the future, some new processing program surpasses Pixinsight, the XISF format will not likely be of much use and you may need to batch convert all your old data.
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pfile avatar
yah i agree, fits files are very compatible when they contain 16 bit samples, so i've just stayed with fits. the compression would be nice but of course a single byte error will render the whole file unusable if compression is turned on, so i'm a little reluctant to compress the files. not that that's ever happened but still.
pfile avatar
on this topic though we had someone on the PI forum turn on CFITSIO in nina3 and nina started using 32-bit integer samples, which PI had a hard time converting properly. i'm not sure that's what NINA intended and it could be a bug.
Scott Badger avatar
XISF, but just so PI doesn’t think less of me……

Cheers,
Scott
Jason Fleming avatar
Scott Badger:
XISF, but just so PI doesn’t think less of me……

Cheers,
Scott

Yeah, the "FITS format is deprecated" message in the log can make you feel judged.  XISF is all I've used for collection since I started using NINA.
Bronco Oostermeyer avatar
I stay on .fits for now. I had the fortune to be one of the first who had SN2023ixf on photo. I handed over my data and noticed that scientist don’t use PI all that much. I could hand over the originals, without conversion. Although the XSIF specs are published, it still feels as a proprietary format. That said, I haven’t looked into adoption of XSIF by other tools.
Frank Butler avatar
I use fits so that I can open with other programs but I do that less and less now. I hadn't realized Xisf would take less space so I might change. Thanks for raising this discussion.
pfile avatar
Frank Butler:
I use fits so that I can open with other programs but I do that less and less now. I hadn't realized Xisf would take less space so I might change. Thanks for raising this discussion.

well on its own XISF won't take less space, you need to enable the option to use compression.
fjwidmann avatar
I use .fits. I download directly to a NAS and never worry about file size.
Rüdiger Patommel avatar
I also continue to use FITS even though I am a PixInsight user. The advantage is that with a FITS viewer (ASI Studio) I have significantly faster access for a quick preview.
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Gary JONES avatar
Hi Richard,
I had this dilemma as well, but now I only ever use FITS for saving raw image files - not XISF.

The main reasons are so I can :-
- browse the raw image files with thumbnails in the Finder
- read the FITS headers in the Finder
- display images and FITS metadata using QuickLook - that applies to MacOS and Windows
- use the files with other image processing applications, such as Affinity Photo.

I honestly cannot see any advantage in saving the raw image files in a proprietary format.

I hope that helps,

Gary
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GergoB avatar
I use XIFS with LZ4HC. It compresses my 120MB files down in the 75-85MB range.
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Richard H avatar
I use .fits. I download directly to a NAS and never worry about file size.

I use a NAS too to save as fits files and I don't have to worry about storage space for a long, long time
scottdevine avatar
Didn't even know there was an option, so thanks for pointing that out.  

As disk space is so cheap, I'll stick with FITS for now.  Nice to have options.
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karolbe avatar
FITS. It is definitely not deprecated, even though some people claim so.
Georg G Albrecht avatar
FITS. There are too many advantages in this file format being red by many other software applications that I don't see a reason for me to restrict myself just because I mostly nowadays process images in PixInsight. Same as for using NINA instead of products that only read "red"…
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