Questions tagged [fits]
The fits tag has no usage guidance.
35
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How to convert .exp files from NRAO VLA Archive to .fits format
I recently downloaded some observational data files from the NRAO VLA Archive, and they have the extension .exp. These are old observations. I need to convert these files to .fits format for further ...
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48
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IRAF mask images with sigma clipping
I have a school homework which MUST use IRAF
First I have to produce a median background from this image
but before fmedian image x y I need to mask out all the ...
- 191
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1
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87
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Plotting scatter graphs with fits binary file?
Basically I'm trying to create code in python which will allow me to open a Fit's binary file, read it and create a scatter diagram with it. Hopefully plotting LogG vs Teff. But it seems like ...
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60
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Crop a FITS file in shape of another
I have a FITS file, let us say file A. I have another FITS file, file B. File B has a smaller footprint than file A. I want to crop file A in shape of file B. How do I go about doing that?
- 304
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44
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CMB maps analysis (Planck, ESA, FITS)
I wanted to analyze Planck mission FITS files and was wondering about the parameters. So the map uses color coding for temperature-based anisotropies right? So the maximum angular resolution is ...
- 161
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36
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Not finding some FITS Spectra files in SDSS
I'm trying to automate downloading FITS files from SDSS. Currently, I'm getting information on the plate, mjd, and fiberID of certain objects from an SQL query on SpecObj, which I'm using in an url ...
- 13
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49
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ds9 configuration issue
I'm trying to use DS9 for X-ray image analysis. Before that I have to configure it for use, I need to click on option using web proxy.
Beside use internal web browser checkbox there should be another ...
- 21
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61
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Creating a small data pipeline
I wanted to create a small data pipeline such that it consists of images of sky in the filters F125W, F160W, F606W and F850LP. The 4 images for a single object should be in a single FITS File which ...
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1
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248
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Plot several FITS files in one graph
At the moment, I get three separate graphs. Ideally I would like to overlay all graphs, so that I only have one plot with multiple FIT files.
I have a folder on my desktop with the HARPS-N data, the ...
- 1
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241
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Split Multi-Extension fits file - fits.fz format
I have CFHT/MegaCam fits.fz file on which I want to do photometry. I want to split these large fits.fz file into separate CCD detector fits and then run Source Extractor on them for photometric ...
- 111
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399
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What do the negative values in FITS images mean?
I am using FITS images, and noticed negative values in value matrix. What they mean? For example, for one of the images, the minimum value is -0.34472656 and the maximum = 552.0. The data type(format) ...
- 51
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443
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Making RGB image using FITS files with different dimensions
I want to make an RGB image using 3 FITS files: one IR image from Spitzer and the other two from UVIT. I tried to make them using make_lupton_rgb in Astropy, but it doesn't work in the case of FITS ...
- 304
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1
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590
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How to slice WCS in a FITS file?
I have three WCS axes in a FITS image. I want to slice the axes and use only the first one. Note that though there are three axes, the WCS is superimposable. So there is no worry about a shift in WCS ...
- 304
3
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1
answer
57
views
Frequency coverage for first spectral channel of .fits cube?
A .fits cube has 3 dimensions, where the 1st axis is RA, 2nd axis is Declination and 3rd axis is frequency.
My question is rather simple, but causing pain none-the-less. Given a .fits cube, what is ...
- 257
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What do negative values on bright sources in TIRSPEC mean?
I opened a FITs image data from TIRSPEC (NIR imaging) (an HgCdTe infrared imaging sensor) on DS9 and I saw that some of the bright stars have black patches at the center (negative values).
Can you ...
- 503