JWST Pillars of Creation
Posted: Mon Dec 12, 2022 7:07 pm
Fully post-processed in ST 1.9a. All 6 filters used, basically mapped to the same false color hues the same way NASA did. Their version (unsure how they did it, what they used, or how selective they may have been. Though that's perhaps unavoidable trying to mash 6 filters together, and I'm sure my attempt is artsy as well) can be seen here: https://stsci-opo.org/STScI-01GFXR207QM ... QSF3CT.png
This was rather difficult, but I finally got something out of the data. For sure a work in progress, as I made a number of mistakes. What's the SS-Airy Disk % for JWST anyway?
For now, in short, I composited three of the files as RGB (though I used a NB matrix), then used Layer module operations to bring in the other three files, which I had already processed through to matching cropped/binned final images, "mono" but colorized in the Color module to the "correct" hue.
As you can imagine, JWST doesn't quite fit the filter choices in our new composite module options, though it seems your choice there will send you on the path to having green cap or purple cap. Though with funny data like this, I kind of wanted to be able to pick either or both once I got there.
I'll keep trying some different versions of this (maybe changing up my luminance weighting in compose a bit more too), but I'd like to see what others can make of it too.
JWST data can be downloaded from MAST Archives, but usage is a bit awkward. The fits files have multiple images contained within, so you have to extract out the appropriate panel/layer. I've used ASTAP for that before, but this data crashed it. Fits Liberator is ok, but had trouble with the 90 filter, and only saves out as tiff. So I ended up using Gimp.
Then, some JWST filters are taken bin 1, others bin 2, so you sort of have to scale some down to match.
And then there's star registration. No, NASA did not do that for us. This time I couldn't get anything to register/star align these files. ASTAP failed. And, after I cropped edges so each file had the same xy, DSS failed also. So, as I clearly hate myself, I picked a reference file and aligned each file by eyeball/hand in Gimp - using levels stretched images to figure out the scaling, rotation, and xy displacement, and then applying that to a linear version of the file and saving it back out.
Maybe someone can try PI perhaps and see if that program can star align the files?
My extracted, scaled (ballpark 50% for the bin1 files), cropped, and hand-registered files are here in the so-named folder: https://drive.google.com/drive/folders/ ... sp=sharing
There's also a folder linked that's just extracted, scaled, and cropped, but not yet registered, again if anyone can manage to get a program to align them. I'm sure my eyeballed ones are flawed since I could only be so "perfect," and I couldn't do interpolation either.
And again, the originals could be obtained from MAST if you want to start from scratch.