catmag about kv450imsim HOT 8 CLOSED

Just looking at those galaxies with positive weights doesn't help either.

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Hi @arunkannawadi, LensFit does not measure the magnitudes and should simply take, as an input, the measured mags from SExtractor's MAGAUTO column. I'm not understanding what you are trying to match tho? Are you trying to match the input mags from the sims to the CATMAG from LF output catalogue?

from kv450imsim.

Ok, that is helpful. What I did was the match the lensfit output catalogue to the SExtractor catalogue by matching the positions. And then, I compared the catmag and MAG_AUTO fields to find this difference.

I had to match it by positions because I wanted the SExtractor catalogue in FITS format, so I re-ran SExtractor on the image after the pipeline was finished. And I got a different number of objects. That is weird, and I will first look into that.

from kv450imsim.

@arunkannawadi you can simply match SExtractor and LF output catalogues by the Object ID. There is a direct 1-1 link between all items in the SExtractor catalogue and the LF output catalogue.

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The SExtractor catalogue in ASCII format has 61518 galaxies (so does the LensFit catalogue which reads this) whereas when I changed the config file to give me a FITS file and ran it outside the pipeline, I get 63163 objects in my catalogue. I double checked I provide the same inputs as the ones that pipeline.py provides.

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that is really strange, I would expect that ASCII output and the FITS output should remain consistent...

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I knew it had to be something stupid. I was feeding the WEIGHT_IMAGE but not the WEIGHT_TYPE :-/
Now I get the same number of detections and moreover, catmag and the input MAG_AUTO agree very well.

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@arunkannawadi great as long as that is working well :)

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